In this study, B-site Ga-doped Sr₂Fe_1.5Mo_0.5-xGa_xO_6-δ (SFMGx, x=0, 0.1, 0.2, 0.3, 0.4) cathode materials are synthesized by the citric acid~glycine combustion method. The effects of Ga-doping on the crystal structure, electrical conductivity, and electrochemical performance are investigated. The doping of Ga into the SFM leads to lattice shrinkage and increases conductivity in air. Additionally, the introduction of Ga increases the oxygen vacancy concentration, leading to high catalytic activity for oxygen reduction reaction. For all the samples, SFMG0.3 exhibits the best electrochemical performance with the lowest polarization resistance of 0.624 Ω cm² at 600 ℃ in air, reduced by 80.57% compared with the SFM cathode. All of these results indicate that the Ga-doping of SFM can substantially improve the electrochemical performance.

Titanium dioxide (TiO₂) particles were prepared by two different methods based on the sol-gel method, and the methyl orange degradation experiments showed that the catalytic degradation performance of TiO₂ particles prepared by the two-step ethanol method was better than that of TiO₂ prepared by the one-step method, and the surface morphology of the TiO₂ was characterized by scanning electron microscopy (SEM), and the surface morphology of TiO₂ particles prepared by one-step method was characterized by X-ray diffraction (XRD) and the characterization of chalcogenide photovoltaic device performance shows that the TiO₂ particles prepared by the one-step method mainly show anatase phase, and its application in chalcogenide solar cells under the environment of air, the photovoltaic conversion efficiency (PCE) of the cell reaches 12.7%, while the TiO₂ particles prepared by the two-step method appear anatase and rutile two kinds of diffraction peaks, and the mixed-crystalline form makes the PCE of chalcogenide cells decreased to 9.4%, so it can be concluded that TiO₂ prepared by one-step method can improve the performance of calcite solar cells when used as an electron transport layer.

In this study, the corrosion resistance and discharge properties of five alloys of Mg-xSr (x=0.2wt%, 0.5wt%, 1wt%, 2wt% and 4wt%) as anode materials for magnesium-air batteries were systematically studied by electrochemical techniques and magnesium-air battery discharge test. The results show that the corrosion resistance and electrochemical activity of the alloy can be effectively enhanced when an appropriate amount of Sr is added to the magnesium alloy. Among the anodes studied, the Mg-2Sr anode had the highest and relatively stable discharge voltage and the best discharge performance at all current densities, and had the highest anode efficiency of 68% at 40 mA/cm. With the further increase of Sr content, the excess second phase accelerates self-corrosion, and the corrosion resistance and discharge performance of the alloy decrease.

Aqueous zinc-ion batteries (AZIBs) hold great promise for various applications due to the low redox potential of zinc and high energy density. The host cathode for storing Zn²⁺ determines the discharge performance and cycling stability of the battery. Herein, three one-dimensional nanowire structured polymers were prepared using nitrilotriacetic acid (NTA) as a ligand with three carboxyl groups, and three nitrogen-doped carbon nanowires loaded with different particle size MnO materials (MnO/NC-x) were obtained after calcination treatment. Among them, the MnO particles in MnO/NC-0.5 prepared with a Mn²⁺∶NTA ratio of 0.5 had the smallest size and were uniformly dispersed on the nanowire surface. This material exhibited excellent kinetic properties such as ion diffusion and conductivity as the cathode for AZIBs. It delivered a rate capability of 158 mAh/g at a high current density of 2 A/g and still maintained a capacity retention of 96% after 1000 cycles at 1 A/g, demonstrating excellent cycling stability.

High-nickel ternary cathode materials have received extensive attention from researchers due to their advantages, including high energy density, high voltage plateau, and non-memory effect. However, limited by its deficiencies such as poor cycling stability, cations disordering, and poor thermal stability, there remains necessity for extensive and comprehensive research on high-nickel ternary cathodes. This paper focuses on the deficiencies of high nickel ternary cathode materials, and summarized recent advances in modification approaches, encompassing ions doping, surface coating, concentration gradient, co-modification, electrolyte modification and structure regulation in recent years, while also discussing and providing prospects for future research directions.

Ruddlesden-Popper (RP) perovskite oxide has a set of distinct physicochemical characteristics that make it a highly promising anode for solid oxide fuel cells (SOFCs). However, it is hard to use most RP perovskites directly in anodes because they lack reduction resistance, catalytic activity or stability. This review summarizes the internal mechanism of structure adjustability and properties richness of RP oxide based on the brief introduction of its characteristics, and then systematically introduces recent advances in RP oxide as an anode for SOFCs based on the dimension of microstructure, ion substitution sites and preparation process characteristics. Then reviews and discusses the ingenious phase transformation method used in preparing materials and in situ precipitation to improve catalytic activity, and extensively analyzes the design concept of the RP materials and the existing problems. Finally, this review indicates that the substitution with heterovalent ion, the combination of theory and practice, the full use of oxygen non-stoichiometric ratio and hydroxylation ability of RP oxide are important strategies to develop new RP anodes with higher reduction resistance, catalytic activity and stability.

This study proposes a strategy to regulate the microstructure of Mg-1Ge-1In alloy by using the difference in solid solubility of germanium and indium in magnesium. After homogenization annealing, the Mg₂Ge phase in the alloy exhibits a continuous network-like structure. The Mg-1Ge-1In alloy demonstrates exceptional anode discharge performance, encompassing a low corrosion rate of 2.48 mm/y, a discharge voltage of -1.70 V at a discharge current of 1 mA/cm², and a remarkable anode utilization efficiency of up to 59.49% after discharging at 10 mA/cm² for 1 h. In addition, under a discharge condition of 5 mA/cm², the Mg-1Ge-1In alloy maintains a stable voltage, accompanied by a layered peeling phenomenon on its surface. However, as the discharge current increases to 10 mA/cm², the discharge voltage undergoes some decay, accompanied by a decrease in discharge stability. The discharge activation mechanism of the Mg-1Ge-1In alloy is based on the galvanic effect of the Mg₂Ge phase and the oxidation-reduction cycle of In atoms. The discharge active sites originate from the continuous network interface between the Mg₂Ge phase and the magnesium matrix. The addition of In further enhances the activation of the magnesium matrix surface. The synergistic effect of these two factors ensures the stable and continuous progress of the discharge reaction.

Magnesium is an interesting class of solid-state hydrogen storage materials with high hydrogen storage capacity (7.6wt%) and reversible hydrogen absorption and release. However, the high temperature required for Mg hydrogen absorption and release and the slow kinetics of hydrogen release affect its practicality. In this paper, two different types of MXene (Nb₂CCl_x and Ti₂CCl_x) were prepared by the molten salt etching method with the ratio of Mg: MXene = 10: 1, and the effects of the addition of different types of MXene on the microstructure and hydrogen absorption and discharge properties of metallic Mg were investigated. The results showed that the phase composition of the materials remained unchanged, but the particle size of the materials was further reduced after ball milling, which increased their specific surface area. The introduction of Nb₂CCl_x and Ti₂CCl_x, on the other hand, gives Mg a significant enhancement, which can effectively increase the hydrogen absorption and release rate of the material, with Mg@Nb₂CCl_x releasing 5.0 wt% hydrogen in 200 s, and Mg@Ti₂CCl_x releasing 5.3 wt% in 250 s. The introduction of Mg@Nb₂CCl_x can also reduce the initial hydrogen absorption and release temperature of pure Mg by 10wt% Nb₂CCl_x. The initial hydrogen absorption and release temperatures of the materials can also be lowered, with 10wt% Nb₂CCl_x lowering the initial hydrogen absorption and release temperatures of pure Mg by 125 ℃ and 175 ℃, respectively, and 10 wt% Ti₂CCl_x lowering the initial hydrogen absorption and release temperatures of pure Mg by 100 ℃ and 125 ℃, respectively. The results of hydrogen absorption and release kinetic fitting based on the Chou model showed that the addition of MXene shifted the rate-control step of Mg from surface permeation control to diffusion control, which improved the hydrogen absorption and release kinetic performance of Mg.

In order to solve the problems of poor electrical conductivity and low material utilisation of MnO₂ materials in water-based zinc-ion batteries (ZIBs), this paper took agricultural waste coconut shells as raw materials, introduces low-cost, abundant, and green renewable biomass resources into electrode materials, and obtained coconut shell carbon with excellent conductivity through high-temperature carbonization. MnO₂ nanoparticles were grown on the surface of coconut shell carbon by hydrothermal method to obtain coconut shell carbon@MnO₂ composite nanomaterials. By using scanning electron microscopy (SEM), X-ray diffraction (XRD), electrochemical techniques and other characterization testing methods, the morphology, structure, and electrochemical performance of the composite material were analyzed. The results showed that the specific capacity of coconut shell carbon@MnO₂ was still as high as 344.6 mA h/g after 300 cycles at a current density of 100 mA/g, and its performance was much higher than that of commercial MnO₂ materials (64.3 mA h/g). The excellent electrical conductivity of coco carbon@MnO₂, the nanosized structural design improved the material utilisation, reduced the ionic diffusion path, brought faster ionic diffusion rate and improved the multiplicity performance of the material, which had a good application prospect.

Aqueous zinc ion batteries have attracted much attention due to their advantages of higher energy density, low cost and environmental friendliness. Among the commonly used cathode materials for zinc ion batteries, vanadium-based composites have a promising research prospect due to their multiple valence states (V⁵⁺, V⁴⁺, V³⁺, V²⁺) and different structural features, which provide high specific capacity when playing the role of cathode materials for zinc ion batteries. However, vanadium-based composites are limited in the application of zinc-ion batteries due to poor cycling stability and low electrical conductivity. To address this issue, nanoparticles with a larger specific surface area than commercial vanadium pentoxide (V₂O₅) were prepared in this study using a simple hydrothermal method. Such V₂O₅ nanoparticles as cathode materials for zinc ion batteries provide an excellent specific capacity of 364 mAh/g at lower current densities and exhibits a high reversible specific capacity of 156 mAh/g at high current densities. After 200 cycles, its capacity can still maintain 85% of the initial capacity, not only provide better cycling stability than commercial V₂O₅, but also possess higher specific capacity. Based on its simple preparation method and good electrochemical stability, the nanoparticles demonstrate potential applications in negative electrode materials for zinc ion batteries.

A series of Ag₂CrO₄/g-C₃N₄ composites with photocatalytic hydrogen (H₂) production were prepared by in-situ chemical deposition method. The phase composition, functional group structure, microscopic morphology, elemental compositions and their species of the composites were characterized using X-ray diffraction, Fourier transform infrared, field emission scanning electron microscope, transmission electron microscope and X-ray photoelectron spectroscopy. The light absorption properties and photogenerated carrier separation of the samples were investigated by UV-visible diffuse reflectance spectra, photoluminescence spectroscopy and photocurrent testing. The H₂ production performance of the photocatalysts and the influencing factors were investigated experimentally. The results showed that the introduction of Ag₂CrO₄ did not change the originally heterocyclic structure of g-C₃N₄, and nanostructure Ag₂CrO₄ was dispersed on the surface of g-C₃N₄. Although Ag₂CrO₄ had no H₂ production effect, the H₂ production rate of the composite increased first and then decreased with the increase of Ag₂CrO₄ content. The H₂ production rate of the optimal photocatalyst Ag₂CrO₄/C₃N₄-4% was 2.7 times that of pure g-C₃N₄. The reason was mainly attributed to the appearance of Z-type heterojunction between of Ag₂CrO₄ and g-C₃N₄, which broadened the visible light response range of g-C₃N₄, reduced the charge transfer impedance, and promoted the separation and migration of photogenerated carriers.

Carbon based materials are currently the most commonly used electrode materials for lithium-ion batteries, although significant capacity loss in carbon based lithium-ion batteries (LIBs) is caused by low temperature. In this paper, porous carbon was prepared from rice husks through high-temperature carbonization. Porosity provides more transport pathways and active sites for Li⁺, as well as promotes the transport and diffusion. The results indicated that carbonization temperatures have an impact on the microstructure of rice husk derived active carbon (RHC), and the performance of batteries constructed based on various RHC electrodes was different. The RHC-10 negative electrode obtained at 1 000 ℃ has the highest residual reversible specific capacity, reaching 230 mA/g at 0.2 C magnification and 147 mAh/g at 2 C magnification after 100 cycles, respectively. After 10 cycles at different magnification, the highest reversible specific capacity can still be maintained when cycling again at 0.2 C magnification. The reversible specific capacity can reach 175 mAh/g and 98 mAh/g at -20 ℃ and -40 ℃, respectively, demonstrating excellent low-temperature charging and discharging performance.

Using titanium tetrachloride as the raw material, TiCl₄ was prepared into a 0.5mol/L aqueous solution in an ice water bath under weakly alkaline conditions. The precipitate was obtained by low-temperature hydrolysis, and the precipitate was dried in a vacuum oven at 80 ℃ and roasted at low temperature of 400 ℃ for 12 hours to obtain white powder. Structural characterization was carried out through X-ray diffraction (XRD). The morphology was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The obtained sintered products were combined with metal lithium electrode materials and polyethylene separators to construct a semi battery system for battery performance testing. The results showed that titanium tetrachloride was used as the raw material to achieve slow hydrolysis under low temperature conditions, and then subjected to long-term low-temperature calcination to obtain a white powder of nanoscale rutile type TiO₂, which has advantages such as small particle size, good dispersibility, narrow particle size distribution, and good sphericity. This product has a first discharge specific capacity of 169 mAh/g at 0.2 charge and discharge, and a discharge specific capacity of 69 mAh/g at 5 C, with a capacity retention rate of 91.69%, respectively. Its electrochemical performance is much higher than that of commercial TO₂. Research has shown that the method of preparing TiO₂ based on slow hydrolysis low-temperature sintering mechanism is a simple, low-cost, and suitable process for large-scale production.

Ideal polymer binders for sulfur cathodes should have abundant polar groups for effective polysulfide adsorption to suppress the shuttle effect, together with good binding properties. Herein, a nitrogen-rich complex binder (CS&PEI) is synthesized via aqueous mixing of chitosan (CS) with polyethyleneimine (PEI) containing profuse NH₂ groups. The CS&PEI binder shows advantageous binding performance and polysulfide adsorption over the CS counterpart. As a result, improved rate capability and long-term cyclic stability are exhibited by lithium-sulfur battery assembled from the cathodes with the CS&PEI binder. The specific capacity is retained as 814 mAh/g after 150 cycles at 0.2 C, contributed by the suppressed shuttle effect and the integrated cathodes upon cycling.

The magnesium-air battery has garnered significant attention due to its high energy density and environmental friendliness. However, the magnesium anode/electrolyte interface suffers from irreversible electrolysis-deposition, anode self-corrosion, and hydrogen evolution issues, which severely impact the battery's stability, safety, lifespan, and power density. Electrolyte modulation is a crucial approach to enhancing the properties of the anode/electrolyte interface and consequently improving the overall performance of magnesium-air batteries. This article provides an overview of recent research and developments in electrolyte additives and novel electrolytes for magnesium-air batteries. Electrolyte additives can be categorized into three major classes: inorganic, organic, and composite. They have the potential to suppress anode corrosion, enhance ionic conductivity, and improve anode efficiency. Novel electrolytes primarily encompass new aqueous electrolytes and gel-based electrolytes. The former can mitigate detrimental side reactions, such as hydrogen evolution, while the latter can prevent electrolyte leakage and offer high ionic conductivity with low leakage current. The development of more novel electrolyte additives and innovative electrolytes holds promise for enhancing the performance and stability of magnesium-air batteries in the future.

Due to the high theoretical capacity, Co₃O₄ has been regarded as one of the popular candidates for new anode materials in lithium-ion batteries recent years. However, the poor conductivity and cycling performance hinder its further development. In this work, Co₃O₄/C three-dimensional conductive networks with carbon nanotubes and graphene as conductive bridges and shells were prepared through carbonization and oxidation treatment using melamine and g-C₃N₄ as carbon sources and ZIF-8@ZIF-67 as self templates. The strategy of nanosizing particles and the evaporation and pore formation of zinc at high temperature result in the specific capacity of 1 139.7 mAh/g and 1 002.1 mAh/g after cycling for 200 and 800 cycles at current densities of 0.5 A/g and 2 A/g. Gradually increasing the current density of charging and discharging from 0.2 A/g to 10 A/g and then returning to 0.2 A/g, the material still reaches 94.9% of the initial capacity. This network structure exhibits superior cycling and rate performance compared to similar materials.

Rechargeable zinc ion batteries (RZIBs) have gained significant attention due to their high safety, low cost, and environmental friendliness. However, the high reactivity of water in traditional aqueous electrolytes leads to the problems of dendrite formation and side reactions in the circulation process of zinc anode, which limits the development of RZIBs. These issues are effectively addressed by eutectic electrolytes through the regulation of the number of water molecules in the solvation structure of Zn²⁺ ions via hydrogen bonding and coordination effects. Additionally, eutectic electrolytes have the advantages of simple synthesis, non-corrosive, and environmental friendliness, which has attracted much attention in the field of RZIBs. The article begins by providing a brief introduction to the basic principles and definitions of eutectic electrolytes, and then highlights their current applications in RZIBs. Finally, the development prospects of eutectic electrolytes are discussed, offering important insights for the preparation of excellent eutectic electrolytes.

Capturing water from air is an effective method to solve the current fresh water shortage crisis because of its low construction cost, ease of use and flexibility, as well as the abundance of fresh water resources in the atmosphere. The sorption-absorption method of AWH is the most promising method with stable efficiency and green features. Insufficient water sorption capacity and high desorption temperature of hygroscopic materials are the core problems which limit the wide application of air extraction technology. Covalent organic framework is a new porous crystalline material with large specific surface area and permanent porosity, which is achieved wide attention in the field of gas sorption and storage. The β-ketoenamine COFs:TpPa-1 with high crystallinity and good water stability are prepared by the solvothermal method. The specific surface area of TpPa-1 is 502 m²/g, and the pore size is distributed at 1.26 nm, which makes TpPa-1 have excellent water adsorption ability at low relative humidity. TpPa-1 exhibits an S-shaped sorption isotherm with a steep increase in water sorption capacity from 0.08 g/g to 0.27 g/g under 20%-30% RH. In the sorption kinetics test, TpPa-1 reaches the sorption equilibrium within 2 h at 15 ℃ and 30% RH. Meanwhile, TpPa-1 has a low desorption temperature and may reach 91% desorption efficiency under a standard sunlight (AM 1.5 G), indicating that TpPa-1 may fully drive the desorption process by sunlight irradiation without any energy input. Especially, TpPa-1 exhibits excellent cycling stability after 10 sorption-desorption cycles (1 400 min) under humid conditions (60% RH), and the water absorption rate only decreases by 1.48%. A simple AWH device is designed filling with TpPa-1, and AWH tests are conducted under simulated laboratory conditions. It is observed that 0.225 g/g fresh water may be collected in one cycle under 60% RH condition. This work implies that the porous TpPa-1 may provide a stable strategy for adsorption-assisted air collection with high efficiency and fast cycling.

A perovskite solar cell absorbing layer CH₃NH₃PbI₃ thin film was prepared using a one-step spin coating method. Urea was added during the preparation of the absorbing layer, and the effect of urea doping on the phase structure and microstructure of CH₃NH₃PbI₃ thin films was studied, as well as on the photoelectric performance of perovskite solar cells assembled. The samples were characterized by XRD, SEM, UV-Vis, PL and J-V curves. The results showed that the addition of appropriate amount of urea increased the crystallinity of CH₃NH₃PbI₃ film, improved its orientation and coverage, and reduced the number of pores and cracks. When the doping amount of urea was 10 mol%, the grain size of the film was the most uniform and the crystallization performance was the best. All CH₃NH₃PbI₃ thin films have absorption edges around 780 nm and a bandgap width of 1.5 eV. The addition of appropriate amount of urea improved the absorbance and emission peak intensity of CH₃NH₃PbI₃ film. With the increase of urea doping amount, the absorbance and emission peak intensity of CH₃NH₃PbI₃ film first increased and then decreased. When the doping amount of urea was 10 mol%, the absorption property of CH₃NH₃PbI₃ film was the best, and the emission peak intensity was the highest. 30 perovskite solar cells were assembled using CH₃NH₃PbI₃ thin films with different levels of urea doping, and the J-V curves were tested. When the doping amount of urea was 10 mol%, the cell had the best photoelectric performance, and its solar-cell efficiency reached the maximum of 20.61%. The above analysis shows that the optimal doping amount of urea is 10 mol%.

Organic framework compounds have great application potential in photocatalytic water hydrogen production due to the advantages of controllable molecular structure, large specific surface area, high porosity, dispersed chemical active sites and good stability. In this paper, the metal-organic framework NH₂-UiO-66 was introduced into the synthesis process of the covalent organic framework PyPD-COF by solvothermal method, and NH₂-UiO-66/PyPD-COF heterojunction was formed in situ. The samples were characterized by TEM, EDS, XPS, FTIR, UV-Vis and photocurrent analysis, as well as photocatalytic performance test. The constructed NH₂-UiO-66/PyPD-COF heterojunction could not only retain the excellent properties of the original MOF and COF components, but also form bonds at the heterogeneous interface. It is beneficial to promote interfacial charge transfer, reduce electron-hole recombination rate, and increase photocatalytic hydrogen production efficiency to 20.68 mmol/(h·g), which is 86 times and 3 times of the original NH₂-UiO-66 and PyPD-COF, respectively. At the same time, the covalent bond at the interface makes the composite sample have good hydrogen production stability, which provides a new strategy for the construction of efficient photocatalytic decomposition of aquatic hydrogen heterojunction photocatalysts.

Porous silicon is a semiconductor material with a nanostructure formed by electrochemical etching or appropriate chemical etching of single-crystal silicon wafers. With huge specific surface area, tunable optical properties and good compatibility, porous silicon nanomaterials are widely used in electronic devices, drug delivery, biochips, bio-sensing, chemical sensing, energy conversion and many other applications. The challenge of current research is to develop simpler and more efficient methods for the synthesis of porous silicon nanomaterials and to improve the performance of porous silicon in practical applications. This paper reviews the preparation of porous silicon nanomaterials and their photoluminescence applications in the field of solar cells.

Silane and ethylene were deposited on the surface of conductive carbon black by fluidized-bed method, and then solid phase sintering was used to prepare the silicon carbon co-coated conductive carbon black anode material for lithium ion batteries with excellent cyclic properties. The process parameters of silane and ethylene co-deposition were optimized by fluidized bed. The inlet ratio, silane concentration, codeposition temperature and solid sintering temperature of silane and ethylene were obtained. The phase, microstructure and electrochemical properties of the samples were characterized. The test results show that when the silane and ethylene feed ratio is 2∶1, the codeposition temperature is 500 ℃, and the solid phase sintering temperature is 800 ℃, the co-coated conductive carbon black has the best performance as the anode material of lithium-ion battery. The charge and discharge efficiency of the first circle is 88.19%, and the specific charge and discharge capacity of the first circle is 2 205.0 mAh/g. After 25 cycles, the specific capacity of charge and discharge is 1010.0 mAh/g.

For perovskite solar cells, the preparation of high-quality perovskite thin films is particularly critical. A perovskite solar cell absorbing layer CH₃NH₃PbI₃ thin film was prepared with N-dimethylformamide (DMF) as an organic solvent using a one-step spin coating method. The effects of different annealing temperatures on the crystal structure, microstructure, and optical absorption properties of CH₃NH₃PbI₃ thin films were studied, and based on this, a solar cell was prepared and its photoelectric performance was tested. The results showed that the change in annealing temperature didn't change the main phase structure of CH₃NH₃PbI₃ thin film, but after annealing temperature exceeded 100 ℃, the evaporation rate of DMF increased, and the amount of residual PbI₂ increased, resulting in a decrease in the purity of the film. As the annealing temperature increased, the grain size of CH₃NH₃PbI₃ thin film continued to increase, and the absorbance first increased and then decreased. When the annealing temperature was 100 ℃, the grain size distribution uniformity of the film was the best, with a high coverage rate, and the absorbance reached its maximum, resulting in the best absorbance performance. The photoelectric conversion efficiency of perovskite solar cells assembled with CH₃NH₃PbI₃ thin films first increased and then decreased with the increase of annealing temperature, when the annealing temperature was 100 ℃, the short-circuit current density (Jsc), filling factor (FF), and photoelectric conversion efficiency (PCE) of the battery were all at their maximum values, which were 20.04 mA/cm², 70.58% and 15.38%, respectively. The photovoltaic performance of the battery was the best.

Hydrogen production from electrolytic water is a promising green technology, and the use of low-cost carbon materials loaded with noble metals as catalyst substrates is an effective means to reduce the noble metal loading and optimize the performance of hydrogen precipitation catalysts. Herein, Pt/N-Mo₂C NFs were prepared by using ligand polymerization method to obtain precursor microspheres with high specific surface area formed by the self-assembly of nanosheets through pH regulation, and then Pt nanoparticles were uniformly loaded on the surface of nitrogen-doped molybdenum carbide by ion exchange and high temperature roasting. Due to the high dispersion of Pt nanoparticles on N-Mo₂C with multilayered structure and the synergistic effect between Pt and N-Mo₂C substrates, it exhibits very good hydrogen evolution reaction performance. The Pt/N-Mo₂C NFs possess low overpotentials (44 mV/η₁₀ and 137 mV/η₁₀₀), and Tafel slope of 46.2 mV/dec, as well as good stability. The results of this paper have implications for the design of low loading noble metal catalysts.

Fe₂O₃/C negative electrode materials were prepared using nano Fe₂O₃ and acetylene carbon black as raw materials by adding different mass fractions (25%, 35%, 45%, 55%) of acetylene carbon black. The effect of acetylene carbon black ratio on the crystal structure, micromorphology and electrochemical performance of Fe₂O₃/C anode materials was studied. The results showed that the Fe₂O₃/C negative electrode material had a high crystallinity, belonged to a hexagonal crystal system structure, and presented microspheres like particles. Adding an appropriate amount of acetylene carbon black improved the uniformity of the distribution of Fe₂O₃ particles. Fe₂O₃ nanoparticles were connected by acetylene carbon black, forming a dense and uniform grid structure. The CR2025 button battery was prepared using Fe₂O₃/C as the negative electrode material. With the increase of the doping amount of acetylene carbon black, the first discharge capacity of Fe₂O₃/C negative electrode material showed a trend of first increasing and then decreasing. When the doping amount of acetylene carbon black was 45 wt%, the first discharge capacity of Fe₂O₃/C negative electrode material reached a maximum of 483.6 mAh/g. As the number of cycles increased, the specific discharge capacity attenuation of the battery gradually increased, and a wide discharge plateau appears around 0.15 V during the discharge process. When the doping amount of acetylene carbon black was 45 wt%, the specific discharge capacity of Fe₂O₃/C negative electrode material decreased to 115.6 mAh/g and the retention rate reached 23.91% at 30 charge/discharge cycles. After discharging at current densities of 0.5, 1.0, 2.0 and 3.0 C, and then setting the current density to 0.5 C, the discharge capacity of the battery had a small change and excellent rate capability.

In recent years, nanofibers have excellent properties used in fuel cell materials, which has attracted widespread attention. Electrospinning technology is a low-cost, efficient, controllable, and easy-to-operate fiber preparation method. The micromorphology of the electrode material has a significant impact on cell performance. In this paper, the influencing factors of electrospinning technology are summarized into three categories: internal parameters, process parameters and environmental parameters. The influence of these parameters on the micromorphology of materials is discussed. Furthermore, the fiber structure formed by electrospinning is summarized, with a focus on the performance obtained on different microstructures. In addition, the latest research progress on electrospinning for solid oxide fuel cell materials is summarized. Finally, the development status of composite electrode materials and their microscopic formation mechanism are particularly emphasized, providing research ideas for relevant researchers.

In this work, the valuable metal was recycled and reused by using malic acid as leaching agent and H₂O₂ as reducing agent, and the effect of different factors on the wet leaching efficiency of valuable metals was investigated. Meanwhile, the sol-gel method was utilized to re-synthesized LiNi_1/3Co_1/3Mn_1/3O₂. And the re-synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical tests. The results showed that the wet leaching efficiency of the valuable metals Li, Ni, Co and Mn was reached 97.5% at the conditions of the malic acid concentration of 2.5 mol/L, the solid-liquid ratio of 120 g/L, the synthesized time of 80 min, the synthesized temperature of 90 ℃, and the H₂O₂ amount of 10 vol%. The re-synthesized materials also shows a good crystallization property. After 100 cycles of charge and discharge at 1 C, the specific capacity is 103.4 mAh/g, the capacity retention rate is 85.5%, and the capacity recovery rate is 92.32% after rate charge and discharge.

Manganese dioxide (MnO₂) is widely used in aqueous zinc-manganese batteries due to its high abundance and low cost. Flow batteries can realize the decoupling of energy component and power component, thus they have been paid more attention in the field of long-term large-scale energy storage. In this study, semi-solid electrodes were designed with MnO₂ as the active substance, and a high volumetric specific capacity flow battery was designed. Firstly, semi-solid electrodes were prepared using Xanthan gum as suspension matrix and Ketjen Black as conductive agent, and the optimal ratio of MnO₂ semi-solid electrodes was determined by characterizing the electrochemical properties and rheological properties of the electrodes. The critical concentration for conductivity percolation of Ketjen Black is 9 g/L, and the semi-solid electrodes prepared with this concentration show good rate performance and cycling stability. The volumetric specific capacity of the semi-solid electrodes can reach 32.5 Ah/L with 300 g/L MnO₂. Semi-solid electrodes exhibit non-Newtonian rheology with a yield stress of approximately 2 Pa which can maintain the mechanical stability of the suspensions while the pumping energy loss is low. The volumetric specific capacity of zinc-manganese flow battery with semi-solid electrodes can reach 22.3 Ah/L, showing promising prospects for development.

Zn-ion batteries have attracted much attention due to their high safety and low cost, however, the growth of Zn dendrites hinders the stability of the battery performance. Here, a strategy is proposed to prepare ionogel electrolytes by incorporating ionic liquids into PVDF-HFP substrate. The cations of the ionic liquids can adsorb onto the Zn tips to form a shielding layer for uniform deposition of Zn²⁺. In this work, EMIM(OTf), BMIM(OTf), and HMIM(OTf), that belong to imidazolium ionic liquids, were selected to investigate the inhibitory effect of their cation with different side chain length on the growth of Zn dendrite. It was demonstrated that the ionogel electrolyte, prepared from BMIM(OTf) with moderate side chain length, not only suppressed the growth of Zn dendrites effectively and had high ionic conductivity of 1.87 mS/cm, but also had a stable cycle life of 2500 h. The Coulombic efficiency reached 99.30% after 500 cycles and the capacity retention of the full battery was 83.9% after 200 cycles. This work demonstrates the potential application of ionogel electrolytes in the field of high-performance Zn-ion batteries.

A high specific surface and porous Ni MOF was prepared by chemical method. The catalytic effect of Ni MOF with different contents on the hydrogen storage kinetics of Mg₉₀Ce₅Y₅ alloy was also systematically investigated by X-ray diffractometer (XRD), scanning electron microscope (SEM) and Sievert volumetric methods. The results showed that the addition of Ni MOF substantially improved the ball milling efficiency of Mg₉₀Ce₅Y₅, and the particle size was reduced to less than half of original samples, which improved kinetics of hydrogen absorption and desorption of the alloy, and effectively reduced the activation energy of hydrogen absorption and desorption of samples. With the addition of 3% Ni MOF, it takes 2 min to absorb 90% of the maximum hydrogen absorption at the pressure of 3 MPa and 473 K. It takes only 30 min for complete hydrogen desorption at 573 K, which is 10 times faster than the Mg₉₀Ce₅Y₅. The activation energy is reduced to 69.1 kJ/mol. However, as the added content increases, the maximum hydrogen storage capacity of the composite is significantly reduced.

ZnO quantum dots with different Eu-doped concentrations (0, 0.05, 0.10 and 0.15 mol/L) were prepared based on hydrothermal and spin-coating methods. Photoanode films were prepared on the basis of Eu-doped ZnO quantum dots, and quantum dot sensitized solar cells were prepared as photoanodes. The effects of Eu-doped concentration on the morphology, crystal structure, spectral properties and photoelectric properties of ZnO films were studied. The results showed that Eu-doped ZnO nanorods prepared by hydrothermal method belong to hexagonal wurtzite structure. Eu-doped ZnO nanorods did not produce new products, but refined the diameter of ZnO nanorod array, with a diameter distribution of 45~60 nm and a height of about 1.2 μm. The orientation and uniformity of ZnO nanorods had been improved. Eu doping reduced the band gap width of ZnO, reduced the photoluminescence intensity of ZnO, and improved the separation ability of electron pairs. When the concentration of Eu doping was 0.10 mol/L, the minimum band gap width of ZnO was 3.09, and the photoluminescence intensity was the lowest. The doping of Eu improved the photoelectric performance of the quantum dot sensitized solar cell assembled based on ZnO as the counter electrode. When the concentration of Eu doping was 0.10 mol/L, the photoelectric conversion efficiency could reach 4.03%, the charge transfer impedance of the counter electrode was 1.38 Ω, the exchange current density of the counter electrode was 9.92 mA/cm², and the photoelectric performance was the best.

Direct methanol fuel cells (DMFCs) are one of the clean energy sources for solving the problems of energy shortage and environmental pollution. Methanol oxidation reaction (MOR) and oxygen reduction reaction (ORR) are important electrode reactions for DMFCs, but their large-scale commercialization is limited by sluggish kinetic processes. In recent years, carbon materials have attracted much attention as promising catalysts for DMFCs due to their low cost, high specific surface area and well-developed pore structure. Especially, heteroatom doping (nitrogen, sulfur, phosphorus, and boron) is not only beneficial for improving the surface inertness of carbon to enhance the electrical conductivity and increase the defect sites, but also boosts the electrochemical activity by strengthening the strong metal-support interactions. Therefore, developing heteroatom-doped carbon materials which specialized for catalyst or support toward DMFCs is significant to promote the commercialization of DMFCs. In this review, the common preparation methods of heteroatom-doped carbon materials and their application in ORR and MOR are summarized. Ultimately, it is expected that the future developing direction of heteroatom doping carbonaceous materials is aimed at multicomponent co-doping, promotion of stability and in-depth analysis on catalytic reaction mechanism.

Due to the advantages of abundant earth elements, low toxicity and environment protection, Cu₂ZnSn(S,Se)₄ (CZTSSe) thin-film solar cells are thought to be suitable for the large-scale production in the future. At present, the efficiency of these devices is always limited by the high cation disorder of the absorber layer and the low open-circuit voltage of the device. To solve this problem, the cation doping measure has been proposed by scientists, which is the disorder of cations can be reduced by introducing other cations, improving the photoelectric conversion efficiency of the device. It has also been proved that cation doping is great significant in improving the performance of devices. Based on this, the research progress of cation doping measures in optimizing the performance of CZTSSe devices is discussed in detail, including the additional addition of cations (e g, Na, K, Sb) and cation substitution (e g, substitution of Cu, Zn, and Sn with Li/Ag, Mn/Mg/Ba/Cd, and Ge, respectively). It is concluded that the most promising cations are Cd²⁺ and Ge⁴⁺ ions, considering the toxicity of Cd, Ge should be the most promising element in optimizing the performance of CZTSSe devices.

We synthesized two new sulfite-type compounds as the electrolyte additive: (2-oxido-1, 3, 2-dioxathiolan-4-yl) methyl benzene sulfonate (ODMB) and (2-oxido-1, 3, 2-dioxathiolan-4-yl) methyl 4-methyl benzene sulfonate (ODMM). The cells’ electrochemical performances are characterized by C-rate test, charge-discharge test, electrochemical impedance spectroscopy (EIS). TG-FTIR measurements indicate that ODMB and ODMM both have good thermal stability and their decomposition temperature is 256 ℃ and 255 ℃, respectively. The cell with 0.7 wt% ODMB discharge capacity (147.98 mAh/g) remain at 97.51% of its initial discharge capacity (151.76 mAh/g) after 50 cycles. Scanning electron microscope (SEM) results demonstrate that a denser and stable layer is observed. Moreover, the charge transfer impedance of the electrodes significantly decreases. And wettability measurement shows that the 0.7 wt% ODMB electrolyte exhibits superior wettability than the blank electrolyte, which can effectively ameliorate the cells' assembly process.

In order to decrease wear during the start-stop process of the foil gas bearing for the fuel cell air compressor, a self-lubricating soft coating is required on the surface of the top foil. However, the existing polytetrafluoroethylene (PTFE)-based or epoxy-based soft coating have problems such as high friction coefficient or poor wear resistance. Therefore, in this paper, polyimide(PI)-based solid lubricating coating is prepared on nickel-based superalloy foils. The effects of coating thickness, mass fraction of MoS₂ nanoparticle and temperature on the tribological properties of the coating are studied and compared with commercial PTFE coating. The results show that with the thickness increasing, the friction coefficient of the prepared PI composite coating is basically unchanged at first and then increases, and there is an optimal coating thickness to minimize the friction coefficient. With the mass fraction of MoS₂ nanoparticles increasing, the friction coefficient and wear rate of the PI composite coating first decrease and then increase. When the mass fraction is 2.5%, the friction coefficient of the PI composite coating is as low as 0.173, and the wear rate is as low as 9.14×10^-6 mm³/(Nm). With the temperature increasing, the friction coefficient and wear rate of the PI composite coating first decrease and then increase, and the friction coefficient is in the range of 0.081~0.173, while the wear rate is in the range of 3.77×10^-6~9.14×10^-6 mm³/(Nm). Compared with the commercial PTFE coating, the maximum reduction of friction coefficient of PI composite coating is 43.4%, while the wear rate decreases by nearly two orders of magnitude.

An organic porous material based on tetrapyrrole compounds has the advantages of adjustable porosity, modifiable skeleton, uniform active site, etc. Due to their controllable electronic structure, the performance of tetrapyrrole organic porous materials has attracted widespread attentions in terms of electron and ion transport in various electrochemical energy storage devices. In this paper, the classification of tetrapyrrole porous materials and their preparation strategies were summarized, and the performance in improving the electrochemical properties of battery were reviewed.

The electrode/electrolyte interface is a key factor restricting the high specific energy and electrochemical stability of lithium-ion batteries, and its high-temperature stability has an important influence on the electrochemical performance of batteries. This paper reviews the research progress of the improvement for high-temperature stability of lithium-ion batteries in recent years. The main effects of high temperature environment on electrodes and electrolyte of lithium-ion battery were introduced. From the perspective of electrolyte composition, how to design the electrode/electrolyte interface film which is stable at high temperature was analyzed, so as to effectively improve the high-temperature performance of lithium-ion batteries. Finally, the future development and research direction of high-temperature electrolyte for lithium-ion batteries were prospected.

Interconnect is a critical component in solid oxide fuel cell (SOFC). There is urgent demand to develop interconnect with high performance for SOFC stack commercialization. As the working temperature of SOFC decreasing to intermediate temperature (<800 ℃), high temperature oxidation resistant alloys instead of doped lanthanum chromite (LaCrO₃) ceramic become promising candidate. Besides, to optimize the utilized performance of interconnect, a variety of conductive/protective coatings as well as advanced composites are studied. The present paper provided a critical review of the recent progress of interconnect materials for SOFC. For comparison of the advantages and disadvantages of all kinds of interconnect materials and coatings, the recent progress of newly developed interconnect materials were highlighted. Finally, the outlook of interconnect materials were outlined.

Black Phosphorus has a unique two-dimensional layered folded structure, with unique advantages such as large theoretical capacity, high carrier mobility, low redox potential, anisotropic structure, and adjustable band gap. It has broad application prospects in the fields of energy storage, photocatalytic hydrogen production, and cancer targeted therapy. Especially in the field of electrochemical energy storage, because of its high theoretical specific capacity of 2 596 mAh/g, it has been widely used as anode material for lithium-ion batteries and sodium-ion batteries, and it is an ideal anode material for rechargeable batteries. A comprehensive understanding of the progress in the application of black phosphorus in the field of ion batteries, aiming to lay the foundation for the subsequent structural design of black phosphorus and pave the way for the vigorous development of the energy storage field.

The all-solid-state lithium battery has the advantages of high safety and reliability, high energy density, long cycle life, wide electrochemical window, and good high temperature adaptability. However, the main bottleneck restricting its practical application lies in the interface between the electrode and the solid electrolyte, such as Li dendrites and volume expansion in the anode interface region, as well as structural changes, space charge layer and side reactions in the cathode interface region. Graphene is widely used in the field of electrochemical energy storage due to its special 2D structure, excellent electrical conductivity, thermal conductivity and mechanical properties. In this paper, the authors review the research progress on the modification of electrode/solid electrolyte interface with graphene, and prospect the application of graphene in solid-state batteries.