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Aqueous zinc metal batteries (AZMBs) have emerged as a focal point of interest in academic research and industrial strategic planning. Zinc powder (ZP) is poised to assume a prominent position in both future research and practical applications due to its high Zn utilization rate and processability. However, critical challenges need to be addressed before realizing substantial progress. Notably, severe voltage polarization and gas production of ZP electrodes stand out as the primary causes of battery failure, differing with zinc foil where short circuits caused by zinc dendrites contribute to battery failure. While numerous comprehensive reviews have offered effective strategies for zinc foil, a systematic summary of ZP electrodes is still lacking. For ZP, electrode preparation dictates the performance. This review summarizes the criteria for optimal ZP electrodes, covering electrode components, preparation methods, and technique parameters. It emphatically introduces the underlying causes and strategies of water‐related side reactions and briefly analyzes the stripping/plating behaviors of ZP electrodes. The status quo of ZP‐based batteries is then discussed in categories of ZP, current collector, conductive scaffold, binder, and electrolytes. Finally, potential avenues for future research are proposed from three aspects to enhance the focus on ZP electrodes and facilitate the practical application of AZMBs. [ABSTRACT FROM AUTHOR]

A novel sheet-like tin-based metal–organic framework exhibited a specific capacity for lithium storage as high as 1033.3 mAh g−1 at 200 mA g−1 with excellent cycling stability. This framework, due to its unique porous structure and multiple lithium storage sites, could better cope with challenges occurring during lithium insertion/extraction than could traditional tin materials. [ABSTRACT FROM AUTHOR]

Converting superfluous CO2 into value-added chemicals is regarded as a practical approach for alleviating the global warming problem. Powered by renewable electricity, CO2 reduction reactions (CO2RR) have attracted intense interest owing to their favorable efficiency. Metal catalysts exhibit high catalytic efficiency for CO2 reduction. However, the reaction mechanisms have yet to be investigated. In this study, CO2RR to CH3OH catalyzed by CuAg bimetal is theoretically investigated. The configurations and stability of the catalysts and the reaction pathway are studied. The results unveil the mechanisms of the catalysis process and prove the feasibility of CuAg clusters as efficient CO2RR catalysts, serving as guidance for further experimental exploration. This study provides guidance and a reference for future work in the design of mixed-metal catalysts with high CO2RR performance. [ABSTRACT FROM AUTHOR]

The efficacy of lithium-sulfur (Li-S) batteries crucially hinges on the sulfur immobilization process, representing a pivotal avenue for bolstering their operational efficiency and durability. This dissertation primarily tackles the formidable challenge posed by the high solubility of polysulfides in electrolyte solutions. Quantum chemical computations were leveraged to scrutinize the interactions of MXene materials, graphene (Gr) oxide, and ionic liquids with polysulfides, yielding pivotal binding energy metrics. Comparative assessments were conducted with the objective of pinpointing MXene materials, with a specific focus on d-Ti3C2 materials, evincing augmented binding energies with polysulfides and ionic liquids demonstrating diminished binding energies. Moreover, a diverse array of Gr oxide materials was evaluated for their adsorption capabilities. Scrutiny of the computational outcomes unveiled an augmentation in the solubility of selectively screened d-Ti3C2 MXene and ionic liquids—vis à vis one or more of the five polysulfides. Therefore, the analysis encompasses an in-depth comparative assessment of the stability of polysulfide adsorption by d-Ti3C2 MXene materials, Gr oxide materials, and ionic liquids across diverse ranges. [ABSTRACT FROM AUTHOR]

The conventional Haber‐Bosch method for the ammonia synthesis process requires high temperature and pressure. Electrochemical synthesis of ammonia, an emerging ammonia synthesis technology, is a promising approach for sustainable ammonia production that is energy‐efficient and free of greenhouse gas emissions. The design and development of high‐performance catalysts are the keys to promoting the sustainable ammonia production process. This work synthesized a PdCu alloy catalyst loaded on a graphene oxide carrier through a simple liquid phase reduction method. Which greatly enhanced the catalytic performance with an ammonia yield of 1.62 mg h−1cm−2 and Faradaic efficiency of 38.2 % under the nitrate reduction ammonia synthesis (NO3RR) reaction at an overpotential of −0.4 V. For the nitrogen reduction ammonia (NRR), the ammonia yield was 20.83 μg h−1 cm−2 with a Faradaic efficiency of 3.8 %. This study may provide a new idea for material design and promote ammonia synthesis development under ambient conditions. [ABSTRACT FROM AUTHOR]

This study introduces a versatile electrolyte additive, nicotinamide, for zinc anodes, aiming to facilitate uniform deposition and suppress water-induced side reactions. The molecular structure, consisting of a pyridine ring and an amide function group, endows NTA molecules with the ability to regulate electrolyte pH, enhance nucleation overpotential, and constrain 2D diffusion of Zn2+. As a result, the full battery configuration with this additive achieved an impressive lifespan of over 10 000 cycles. [ABSTRACT FROM AUTHOR]

The solar‐driven interfacial evaporation system has attracted much attention in recent years due to its reduced heat loss and accelerated steam generation. As a low‐cost and readily available resource, wood is widely applied as photothermal materials in solar‐driven interfacial evaporation system because of its superior water transfer and heat loss prevention properties. Herein, a simple, mild, and cost‐effective method is employed to fabricate wood‐based photothermal materials. The results demonstrate that the solar absorption rate of wood‐nigrosine is more than 97.5% across a wide wavelength range (200–2500 nm), and an evaporation rate of 1.46 kg m−2 h−1 and evaporation efficiency (86.1%) are achieved under 1‐sun illumination (100 mW cm−2). The solar‐driven interfacial evaporation system based on wood‐nigrosine exhibits strong structural stability and processing capability for dyes and seawater. [ABSTRACT FROM AUTHOR]

As electron transport layers (ETLs) in perovskite solar cells (PSCs), tin oxide (SnO2) possess high carrier mobilities with appropriate energy band alignment and high optical transmittance. Herein, SnO2 ETLs were fabricated by intermediate‐controlled chemical bath deposition (IC‐CBD) at ultralow temperature, where the chelating agent effectively altered the nucleation and growth process. Compared with conventional CBD, SnO2 ETLs fabricated by IC‐CBD had lower defects, smooth surface, good crystallinity, and remarkable interfacial contact with perovskite, resulting in good quality of perovskite, high photovoltaic performance (23.17 %), and enhanced stability of devices. [ABSTRACT FROM AUTHOR]

The environment-friendly electrochemical nitrogen reduction reaction (NRR) is considered to be a promising alternative to the traditional Haber–Bosch process for ammonia production. However, the stability of nitrogen and competitive hydrogen evolution reaction (HER) lead to low faradaic efficiency (FE) and ammonia selectivity for the NRR. Compared with the NRR, the electrochemical nitrate reduction reaction (NO3RR), with no process of N2 adsorption, exhibits a higher NH3 yield and FE. In this work, the MIL-101(Fe) is synthesized and composited with Nb2C MXene, which exhibited excellent NRR and NO3RR performance. For the NRR, the MIL-101(Fe)@Nb2C achieved an ammonia yield of 8.92 μg h−1 cm−2 and a high FE of 20.77%. Meanwhile, for the NO3RR, it achieved a large NH3 yield of 199.68 μg h−1 cm−2 and a high FE of 89.9%. In addition, MIL-101(Fe)@Nb2C exhibits excellent stability for the NRR and NO3RR. DFT calculations proved that the interfacial interaction between Nb2C and MIL-101(Fe) acquired a significant synergistic mechanism to improve the catalytic performance. Since the NH3 yield and FE of the NO3RR are much higher than those of the NRR, it is vital to design NRR catalysts that can easily adsorb and activate nitrogen as well as inhibit the HER. [ABSTRACT FROM AUTHOR]

The photoelectric properties of nontoxic Sn‐based perovskite make it a promising alternative to toxic Pb‐based perovskite. It has superior photovoltaic performance in comparison to other Pb‐free counterparts. The facile oxidation of Sn2+ to Sn4+ presents a notable obstacle in the advancement of perovskite solar cells that utilize Sn, as it adversely affects their stability and performance. The study revealed the presence of a Sn4+ concentration on both the upper and lower surfaces of the perovskite layer. This discovery led to the adoption of a bi‐interface optimization approach. A thin layer of Sn metal was inserted at the two surfaces of the perovskite layer. The implementation of this intervention yielded a significant decrease in the levels of Sn4+ and trap densities. The power conversion efficiency of the device was achieved at 14.31 % through the optimization of carrier transportation. The device exhibited operational and long‐term stability. [ABSTRACT FROM AUTHOR]

The photoelectric properties of nontoxic Sn‐based perovskite make it a promising alternative to toxic Pb‐based perovskite. It has superior photovoltaic performance in comparison to other Pb‐free counterparts. The facile oxidation of Sn2+ to Sn4+ presents a notable obstacle in the advancement of perovskite solar cells that utilize Sn, as it adversely affects their stability and performance. The study revealed the presence of a Sn4+ concentration on both the upper and lower surfaces of the perovskite layer. This discovery led to the adoption of a bi‐interface optimization approach. A thin layer of Sn metal was inserted at the two surfaces of the perovskite layer. The implementation of this intervention yielded a significant decrease in the levels of Sn4+ and trap densities. The power conversion efficiency of the device was achieved at 14.31 % through the optimization of carrier transportation. The device exhibited operational and long‐term stability. [ABSTRACT FROM AUTHOR]

The performance of inverted perovskite solar cells (PSCs) is highly dependent on the surface properties of the hole‐transport layers (HTLs). Poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is one of the most widely used HTLs due to its excellent properties. However, some drawbacks severely limit its application in PSCs. Herein, multifunctional bulk organic ammonium salts (BOASs) are deposited onto PEDOT:PSS films and used for interfacial modifications. The BOASs‐modified PEDOT:PSS has better energy‐level alignment with perovskite (PVK) than PEDOT:PSS, resulting in the suppressed voltage loss of PSCs. Depositing BOASs on top of the PSS isolates moisture to inhibit the ionization of sulfonic acid groups, which is beneficial to reduce the acidity and corrosiveness of PEDOT:PSS. In addition, the interfacial modification of BOASs can effectively enlarge the surface energy of PEDOT:PSS films and improve the morphology of the PVK layer. Therefore, the open‐circuit voltage and fill factor of the PSCs based on BOASs‐modified PEDOT:PSS are simultaneously increased to a maximum of 1.03 V and 73%, respectively, resulting in a champion device efficiency of 18.37%. The unencapsulated PSCs based on BOASs‐modified PEDOT:PSS remain more than 80% power conversion efficiency loss after 700 h of exposure to air. [ABSTRACT FROM AUTHOR]

The solar‐driven interfacial evaporation system has attracted much attention in recent years because it avoids dissipating a large amount of energy into the bulk water. As one of the photothermal materials in solar‐driven interfacial evaporation system, wood has been widely applied due to its excellent properties, such as lower density, open micropores, capillary‐induced hydrophilic nature, and low thermal conductivity. However, the complex processing technology and relatively low efficiency of wood‐based photothermal materials limit their application. Herein, to solve these problems, solvothermal and immersion treatment methods by depositing tin sulfide and silver nanoparticles (AgNPs) have been demonstrated. The solar absorption rate of wood‐SnS‐AgNPs is higher than 98% in a wide wavelength range (200–2,500 nm). Results demonstrate that an evaporation rate of 1.53 kg m−2 h−1 and evaporation efficiency (90.12%) are achieved under 1‐sun illumination (100 mW cm−2). The harsh environmental test indicates that the solar‐driven interfacial evaporation system based on wood‐SnS‐AgNPs has excellent structural stability and purification ability of seawater. [ABSTRACT FROM AUTHOR]

Binary transition metal sulfides demonstrate abundant morphological features and high redox activity. By studying the relationship between different morphological characteristics of active materials and electrochemical performance, high-performance supercapacitors can be discovered. In this work, binary Ni3S2/MoS2 composites in situ grow on the current collector Ni foam via electrochemical deposition and subsequently hydrothermal reaction, then it was directly used as a binder-free electrode for supercapacitors. The micro-morphological evolution process was investigated by controlling the hydrothermal time from 3 to 12 h. The electrochemical characterization showed that Ni3S2/MoS2@NF-9 (hydrothermal reacted for 9 h) with fluffy and abundant nanopores demonstrated the highest specific capacity (341.7 C g−1 at 1 A g−1), best rate performance (50% capacity retention from 1 to 20 A g−1), and superior charge transfer ability compared with others. Ni3S2/MoS2@NF-9 was also used as a positive electrode to assemble Ni3S2/MoS2@NF-9//RGO hybrid supercapacitor (HSC), which displayed a specific capacity of 129.2 C g−1 at 0.5 A g−1 and specific energy of 26.9 Wh·kg−1 at 375 W kg−1. [ABSTRACT FROM AUTHOR]

The purification of carbon monoxide in H2-rich streams is an urgent problem for the practical application of fuel cells, and requires the development of efficient and economical catalysts for the preferential oxidation of CO (CO-PROX). In the present work, a facile solid phase synthesis method followed by an impregnation method were adopted to prepare a ternary CuCoMnOx spinel oxide, which shows superior catalytic performance with CO conversion of 90% for photothermal CO-PROX at 250 mW cm−2. The dopant of copper species leads to the incorporation of Cu ions into the CoMnOx spinel lattice forming a ternary CuCoMnOx spinel oxide. The appropriate calcination temperature (300 °C) contributes to the generation of abundant oxygen vacancies and strong synergetic Cu–Co–Mn interactions, which are conducive to the mobility of oxygen species to participate in CO oxidation reactions. On the other hand, the highest photocurrent response of CuCoMnOx-300 also promotes the photo-oxidation activity of CO due to the high carrier concentration and efficient carrier separation. In addition, the in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) confirmed that doping copper species could enhance the CO adsorption capacity of the catalyst due to the generation of Cu+ species, which significantly increased the CO oxidation activity of the CuCoMnOx spinel oxide. The present work provides a promising and eco-friendly solution to remove the trace CO in H2-rich gas over CuCoMnOx ternary spinel oxide with solar light as the only energy source. [ABSTRACT FROM AUTHOR]

SnO2, the most promising alternative to TiO2 as the electron transport layer (ETL), has attracted great attention for perovskite solar cells (PSCs) due to its high bulk electron mobility, good band energy at the ETL/perovskite interface, and high chemical stability. To enable more efficient carrier transfer and extraction, elemental doping with different metal cations has been studied in SnO2 ETLs. However, the systematic investigation of the doping mechanism lag far behind their efficiency promotion. In this paper, elements of the same main group (Li, Na, K) and period (K, Ca, Ga) have been selected for doping in SnO2. The results showed that among the properties of the dopants, the electronegativity has the greatest influence. The smaller the electronegativity of the doping species, the more conducive it is to carrier transmission and separation. The corresponding mechanism was proposed and discussed. At last, an efficiency of 20.92% of PSCs based on SnO2–K was achieved. In addition, the doped SnO2 is more beneficial for the growth of perovskite crystals, thus reducing grain boundaries and enhancing the stability of the device. [ABSTRACT FROM AUTHOR]

Development and utilization of hydrogen energy is an effective way to achieve carbon neutrality, only hydrogen production through electrolytic water splitting meets the goal of zero carbon emission. To facilitate the large‐scale commercialization of water splitting devices, the development of highly efficient and low‐cost catalysts to reduce the energy consumption is essential. MoS2 has been regarded as a promising electrocatalyst to replace platinum in hydrogen evolution reaction due to its low price and unique 2D layered structure. However, the poor conductivity and inert basal planes of MoS2 limited its wide‐spread application. Recently, researches have demonstrated that the conductivity and active sites of MoS2 can be improved by heteroatoms doping or constructing of heterogeneous structures. In this review, the recent progress of Mo‐based catalysts are summarized centered on MoS2 based on interface engineering and anion engineering, including MoS2–MoO2, MoS2–Mo2C, MoS2–MoNx, MoS2–MoP, and MoS2–MoSe2. The preparation method, structure, and performance of the catalysts are introduced and the possible mechanism behind the improved catalytic activity are revealed to give readers an overall comprehension on the progress of the Mo‐based electrocatalysts for hydrogen evolution reaction. In addition, an outlook on future opportunities and development directions of Mo‐based catalysts are proposed to facilitate the development of Mo‐based catalysts for hydrogen production. [ABSTRACT FROM AUTHOR]

Large-scale popularization and application make the role of lithium-ion batteries increasingly prominent and the requirements for energy density have increased significantly. The silicon-based material has ultra-high specific capacity, which is expected in the construction of next-generation high specific-energy batteries. In order to improve conductivity and maintain structural stability of the silicon anode in application, and further improve the energy density of the lithium-ion battery, we designed and synthesized carbon-coated porous silicon structures using diatomite and polysaccharides as raw materials. The electrode materials constructed of diatomite exhibit porous structures, which can provide fast transport channels for lithium ions, and effectively release the stress caused by volume expansion during cycling. At the same time, the electrical conductivity of the materials has been significantly improved by compounding with biomass carbon, so the batteries exhibit stable electrochemical performance. We systematically studied the effect of different contents of biomass carbon on the Li2MnSiO4/C cathode, and the results showed that the carbon content of 20% exhibited the best electrochemical performance. At a current density of 0.05C, the capacity close to 150 mAh g−1 can be obtained after 50 cycles, which is more than three times that of without biomass carbon. The silicon-based anode composited with biomass carbon also showed excellent cycle stability; it could still have a specific capacity of 1063 mAh g−1 after 100 cycles at the current density of 0.1 A g−1. This study sheds light on a way of synthesizing high specific-capacity electrode materials of the lithium-ion battery from natural raw materials. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) have been rapidly developed as an effective replacement or supplement for lithium-ion batteries (LIBs) due to the high natural abundance and low cost of sodium resources. Sodium super ion conductor (NASICON)-type materials have high ionic conductivity and excellent structural stability, making them one of the potential electrode candidates for SIBs. V(vanadium)-based polyanionic compounds have been the most extensively studied NASICON-structure materials. However, the environmental pollution and high-cost issues of V-based materials demand serious consideration. Currently, V-free NASICON-type electrodes have garnered a lot of attention. In this review, V-free NASICON electrodes for SIBs are first systematically summarized. The latest advances in related cathode/anode materials with various metal redox couples are classified and introduced in terms of their preparation method, structural characteristics, and electrochemical performance. Moreover, the performance improvement strategies and future prospects are discussed. It is expected that the insights may inspire future research into the development of more clean, efficient, and low-cost electrodes for SIBs. [ABSTRACT FROM AUTHOR]

Halide perovskites are intensively studied for applications in optoelectronic devices because of their outstanding properties and relatively low cost. However, the common precursor solutions for perovskite fabrication are rather unstable in the presence of moisture and oxygen, limiting the large‐scale low‐cost production of perovskite. Herein, water is used counterintuitively to formulate an ambient stable perovskite precursor, which is peculiar in that it is solid at room temperature but becomes a liquid at 75 °C. The non‐fluidity of the precursor stemmed from the water‐assisted intermediate fiber assembly, conferring high damp air stability. Yet the heat‐liquefiability made the precursor highly processible for perovskite growth, and when guided by polyvinyl pyrrolidone coordination with Pb2+, the perovskite can preferentially grow along the [200] direction, significantly improving the film quality. To demonstrate the utility of the precursor, it has been used to fabricate self‐driven halide perovskite photodetectors, which exhibited a low noise current of 2.0 × 10−14 A Hz−1/2, a high specific detectivity up to 1.4 × 1013 Jones, and high stability of 20 days of operation with only < 5% external quantum efficiency decay. This type of solid‐liquid convertible precursor opens up new opportunities for wider applications of perovskites. [ABSTRACT FROM AUTHOR]

The elimination of electron transport layers (ETLs) to fabricate ETL-free perovskite solar cells (PSCs) could save manufacturing costs and time. However, compared with PSCs based on the traditional architecture, ETL-free PSCs suffered low efficiency due to the device shunting and large energy barriers for carriers. Herein, a bifunctional interfacial modification material, 3-aminopropyl trimethoxy silane (APS), is selected and in situ grown on a transparent conducting oxide (TCO). On the one hand, the increased hydrophobicity of APS modified indium tin oxide (ITO) could improve the crystal growth of perovskites, resulting in larger grain sizes and reduced surface defects. On the other hand, the APS modification could improve the energy level alignment of ITO and the perovskite, leading to enhanced electron extraction and hole blocking. The PCE of the ETL-free PSCs based on APS modified ITO reached 19.09%, which was over 60% higher than that of ETL-free PSCs based on ITO. [ABSTRACT FROM AUTHOR]

The elimination of the electron transport layer (ETL) to fabricate ETL-free perovskite solar cells (PSCs) could save manufacturing cost and time. However, the direct contact of the perovskite and transparent conducting oxide (TCO) electrodes results in mismatched energy level alignment and current leakage. Therefore, ETL-free PSCs suffer from unsatisfactory photovoltaic performance. Herein, a special perovskite material with a cascaded band gap, called gradient homojunction perovskite (GHJP), is designed and synthesized by a large cation-assisted method. The inherent nature of GHJP was the type-II cascaded energy level alignment, which could block holes during the electron collection. This facilitated the dissociation of the excitons in the GHJP. Due to the excellent properties, ETL-free PSCs based on GHJP obtained 20.55% PCE, which was over 90% higher than that of ETL-free PSCs based on the control perovskite material. [ABSTRACT FROM AUTHOR]

Summary: The stability and toxicity of perovskite solar cells are still preventing full industrialization. Therefore, lead‐free all‐inorganic double perovskite materials have become the focus of research in recent years. Our group proposed a new narrow bandgap lead‐free double perovskite solar cell using a high‐quality Cs2PtI6 film. In this paper, for the purpose of exploring the trend in the bandgap and stability of the perovskite‐derived Cs2PtI6 substituted by halogen ions, we performed a first‐principles investigation based on density functional theory to study the structural and electronic properties of Cs2PtI6−yCly, Cs2PtI6−yBry, Cs2PtBr6−yCly (y = 0, 1, 2, 3, 4, 5, 6). The calculated structural parameters revealed a good mechanical stability for all these compounds, and the trend in the formation energy indicated that the substitution of I− with Cl− and Br− can significantly reduce the energy and improve the thermodynamic stability. Through a comparative analysis of the electronic properties of Cs2PtX6 (X = Cl, Br, I), we found that the substitutional doping of halogen ions can effectively adjust the bandgap and show an obvious change trend. The present study may demonstrate an effective theoretical guidance for preparing lead‐free all‐inorganic perovskite solar cell materials with appropriate bandgap and excellent stability. [ABSTRACT FROM AUTHOR]

Fuel cell is an emerging technology for energy conservation and environmental protection, with simple structure and high energy conversion efficiency. However, the kinetics of cathode ORR is slow. Therefore, high-performance, highly selective catalysts are urgently needed. This work aims to use the DFT to conduct structural design and performance optimization of Ni/CNTs and Ni/X-CNTs (X=B, N, O) catalysts. Studies showed that the number of Ni atom loading, the number and types of doping of heteroatoms all affected the activity of catalysts to some extent. The adsorption energy of O2 was calculated to determine that O2 was adsorbed on Ni(6)/B(2)-CNTs in the Bridge mode. Meanwhile, the comparative analysis of 2 e− path and 4 e− path indicated that ORR occurred in Ni(6)/B(2)-CNTs in acidic medium was more inclined to follow the 4 e− path. The present work has some reference and value for specific experiments. [ABSTRACT FROM AUTHOR]

Compared with the energy‐intensive Haber‐Bosch process, the electrocatalytic nitrogen reduction reaction (NRR) is a promising approach for sustainable ammonia production. However, the design and development of electrocatalysts with high activity and selectivity is currently a major challenge. In this work, we successfully constructed RuFe bimetallic nanoparticles on a two‐dimensional MXene support (RuFe@MXene) through a simple liquid phase reduction method. Benefiting from the rich surface chemistry and high electronic conductivity of MXene, as well as the synergistic effect between RuFe bimetals, the composite can efficiently synthesize ammonia under environmental conditions. Specifically, the NH3 yield and Faraday efficiency of the prepared Ru0.3Fe0.7@MXene composite catalyst reaches 40.79 μg h−1 cm−2 and 15.25 % at −0.4 V vs. RHE in 0.1 M KOH, which are significantly higher than that of the previously reported Ru@MXene. Moreover, the Ru0.3Fe0.7@MXene catalyst also exhibits outstanding electrochemical stability. The density of state (DOS) and the partial density of state (PDOS) of MXene, Fe@MXene, Ru@MXene, and RuFe@MXene were calculated by DFT to explore the synergistic effect of RuFe on the nitrogen reduction performance of MXene‐based catalysts. This work guides the design of high‐performance NRR electrocatalysts in the future. [ABSTRACT FROM AUTHOR]

Electrochemical nitrogen reduction reaction (NRR), as a green and sustainable ammonia (NH3) synthesis process, is considered to be the most promising alternative to the traditional Haber‐Bosch method for NH3 synthesis. However, this process requires a highly active electrocatalyst to overcome the problems of low NRR activity and selectivity. Herein, we deposited metallic bismuth nanoparticles on two‐dimensional Ti3C2 MXene nanosheets by a simple liquid phase reduction method to synthesize Bi@Ti3C2 nanocomposites. This composite material is a promising electrocatalyst for environmental electrocatalytic N2 fixation to NH3. Unexpectedly, the Bi@Ti3C2 composite obtains an excellent NH3 yield and Faraday efficiency as high as 28.3 μg h−1 cm−2 and 27.2 % at −0.4 V versus reversible hydrogen electrode (RHE) in 0.1 M KOH. The high NRR activity can be attributed to the unique N‐philic and H‐phobic characteristics of Bi atoms and the outstanding electronic conductivity of MXene. Moreover, the Bi@Ti3C2 composite catalyst also exhibited good cycling stability and durability of up to 24 h. This work highlights the potential importance of material design and will also expand the research and exploration of high‐efficiency NRR electrocatalysts. [ABSTRACT FROM AUTHOR]

Controlling the crystallographic orientations of 2D perovskite is regarded as an effective way to improve the efficiency of PSCs based on 2D perovskite. In this paper, five different assistant solvents were selected to unveil the effect of solvents on crystallization and morphology of 2D perovskite in a solvent-assisted method. Results demonstrated that the effect of Lewis basicity on the crystallization process was the most important factor for preparing 2D perovskite. The stability of the intermediate, reacted between the solvent and the Pb2+, determined the quality of 2D film. The stronger the Lewis basicity was, the more obvious the accurate control effect on the top-down crystallization process of 2D perovskite would be. This could enhance the crystallographic orientation of 2D perovskite. The effect of Lewis basicity played a more important role than other properties of the solvent, such as boiling point and polarity. [ABSTRACT FROM AUTHOR]

The large-scale application of clean electrochemical energy storage and conversion systems such as water-splitting devices and Zn–air batteries greatly depends on the development of low-cost and highly efficient electrocatalysts. Transitional metal sulfides (TMSs) have gained great research interest owing to their high intrinsic catalytic activity, adjustable electronic structures, and various crystal structures and phases. Meanwhile, metal–organic frameworks (MOFs) are ideal precursors for the preparation of TMSs due to the diverse metal nodes, organic ligands, topologies, and morphologies of MOFs. In addition, MOFs could act as hosts for the incorporation of guest molecules, which could further expand the metal types of TMSs. In this review, the recent progress of MOF-derived TMS electrocatalysts for hydrogen evolution reactions (HERs), oxygen evolution reactions (OERs) and oxygen reduction reactions (ORRs) are summarized. After a brief introduction to the reaction mechanisms, the preparation strategies, structures, catalytic performances, and catalytic mechanisms of the TMSs are discussed to give readers a comprehensive understanding of this prosperous field. The strategies such as nanostructure engineering, interface engineering and heteroatom doping used to improve the performance of the electrocatalysts are discussed in each section. In addition, bifunctional catalytic performances of the catalysts for overall water splitting and rechargeable Zn–air batteries are illustrated. Furthermore, challenges and opportunities for the future development of this field are proposed. We expect this review could provide guidelines for the design and fabrication of TMSs, and initiate more efforts and new discoveries in this emerging research area. [ABSTRACT FROM AUTHOR]

The rapid development of electric vehicles and consumer electronics places higher demands on the performance of secondary batteries. Tin-based materials are expected to be a commercial anode material candidate of next-generation rechargeable batteries due to their high gravimetric/volumetric capacity. However, tin anodes have large volume changes during charge–discharge cycles which leads to a rapid capacity decay. Emerging tin-based metal–organic frameworks (Sn-MOFs) have recently attracted the attention of researchers. Their characteristics of tunable porosity, huge surface areas and multiple active sites offer a wide range of possibilities for Li/Na ion storage and transport, and the coordination bonds stabilize the Sn atoms to the organic matrix buffering pulverization and aggregation. Besides, MOF-related Sn derivatives could also have novel diverse functional structures and achieve high-rate capacity and excellent cycle stability. In this review, we mainly summarize the structural features, energy storage mechanism, and recent advances in the rational design and preparation of Sn-MOFs and MOF-derived Sn-based composites for LiB and SIB anodes, and current challenges and future directions for further development are discussed. [ABSTRACT FROM AUTHOR]

Due to the low cost and strong hydrophobicity of carbon electrodes, carbon-based perovskite solar cells (C-PSCs) have drawn much attention. Copper(I) thiocyanate (CuSCN) is a favorable hole transport layer in perovskite solar cells (PSCs) because of its high chemical stability, high conductivity, and high hole mobility, but pinholes often appear during CuSCN film fabrication. In this work, organic ammonium salt, phenethylammonium iodide (PEAI), has been applied to modify the CuSCN film. The results indicated that PEAI not only eliminated the pinholes, but also passivated the perovskite film and enhanced the interfacial connection. Therefore, the power conversion efficiency (PCE) of C-PSCs increased by about 11%. The stability test showed that the C-PSCs, without any encapsulation, could maintain 70% of the initial efficiency after storage for 800 h in ambient air with 60%–70% relative humidity at room temperature. [ABSTRACT FROM AUTHOR]

Though perovskite solar cells (PSCs) or modules (PSMs) are being developed at an unprecedented speed, several obstacles remain to their commercialization. One of the difficult problems is the expensive and unstable Au and Ag counter electrode. Therefore, highly effective, stable, and low‐cost counter electrode materials should be explored. Among various counter electrode materials, carbon is one of the most promising substitutes for their rich sources, low cost, outstanding electrochemical performance, and diversified surface functions. This review summarizes recent achievements of carbon counter electrode materials, which included commercial carbon paste, carbon black, graphite, graphene, carbon nanotubes and their synthetic approaches, modifications, and structure‐function relationships. Moreover, large‐scale carbon counter electrode in PSCs or PSMs are specifically discussed. Hopefully, this recapitulative analysis will draw the attention of relevant researchers to re‐understand the importance of counter electrode and clarify what should be noticed to develop qualified counter electrode materials for PSCs or PSMs. [ABSTRACT FROM AUTHOR]

Through theoretical calculation and experimental research, the electrodeposition process of preparing a copper catalyst in an acid electrolyte using polyethylene glycol (PEG), polyethylene imine (PEI), and a PEG and PEI mixture as additives was studied. The cutting-edge molecular orbital information of PEG and PEI was studied through quantum chemical calculations. Molecular dynamics simulations were performed to study the interface interaction between PEG and PEI and the metal surface. The microscopic morphology and crystal structure of the coating were characterized by scanning electron microscopy (SEM) and X-ray diffractometer (XRD). It is found that adding composite additives to the studied acidic copper electroplating could obtain a copper coating with a spherical shape, small particle size, and good dispersion effect. This study proves that a PEI and PEG-based copper plating solution is a promising method for preparing high-performance copper-based catalysts in the acid copper electroplating process. [ABSTRACT FROM AUTHOR]

The presence of organic pollutants in the world is harmful to our existence and the environment. So efficient and energy-saving methods for the degradation of organic pollutants present in the environment are important and beneficial for humans and the environment. The use of emerging photocatalytic technology using semiconductor materials to degrade organic pollutants is an effective method with potential prospects for the future. In this work, quantum chemical calculations and classical molecular dynamics simulations are employed to investigate the performances and related reactivities of sulfide semiconductor materials for the photocatalytic degradation of several common organic compounds. The reactivity of the organics is studied using quantum chemical calculations. The adsorption behaviors of several types of organic compounds on the surfaces of sulfide semiconductors in the gas phase were investigated, then similar adsorption processes in the aqueous phase were studied, and then CdS semiconductors were used to explore the influence of different crystal planes on the adsorption behavior of organic matter. Based on adsorption energy calculations, the best adsorption performance for a specific type of organic matter on a sulfide semiconductor was explored, together with an adsorption comparison in the gas and water phases. The results of this study may provide theoretical guidance for sulfide semiconductor photocatalysis technology and give ideas for subsequent experiments. [ABSTRACT FROM AUTHOR]

Power conversion efficiencies (PCEs) of up to 25.5 % have been reported for perovskite solar cells (PSCs). Thus, they have shown great potential for commercial applications. Therefore, simplifying technological process and reducing production costs have been a widespread concern among scientific and industrial communities. In this study, PSCs are prepared with the simplest device architecture (FTO/MAPbI3/carbon). A high‐quality perovskite film with few interface defects and good carrier transport is obtained by tuning the p‐n properties, matching energy levels, and enhancing carrier collection and transport. A PCE of 12.01 % is achieved, which is the best reported to date for this device structure. The device also shows excellent long‐term stability, owing to the elimination of charge transport layers and the usage of hydrophobic materials. This study provides a new approach to reduce production costs and simplify production of PSCs. [ABSTRACT FROM AUTHOR]

Two dimensional (2D) perovskite materials, are more stable than 3D perovskite materials, which could solve the stability issue of perovskite solar cells (PSCs). However, the photovoltaic conversion efficiency (PCE) of PSCs based on 2D perovskite materials was low, due to the high dielectric and quantum confinement of 2D perovskite. In this work, we propose a solvent-assisted method to prepare 2D perovskite films, where the solvent was distributed in a gradient. Therefore, the top-down crystallization process of 2D perovskite can be accurately controlled. The PCE of PSCs fabricated by the solvent-assisted method was enhanced by 48%, compared with the control device. For the packaged devices, the stability test demonstrated that 94% of the initial PCE was still maintained after 1500 hours of storage (25 °C, RH 40%). After carefully analyzing the photophysical process of the carriers in the PSCs based on 2D perovskite, the enhanced carrier transfer mechanism of the solvent-assisted method has been proposed. [ABSTRACT FROM AUTHOR]

Carbon‐based hole transport material (HTM)‐free CsPbI2Br perovskite solar cells (C‐PSCs) have garnered considerable attention due to their super thermal stability. The energy‐level mismatch between the CsPbI2Br perovskite and carbon electrodes, however, results in major energy loss and reduced power conversion efficiency (PCE) of C‐PSCs. Herein, 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMIMBF4) is used to manage the energy level, reduce defect densities, and improve the interface quality between CsPbI2Br and carbon electrodes. Preliminary results demonstrate that the BMIMBF4 modifier can passivate the surface defects of the perovskite film and reduce the energy‐level mismatch between the CsPbI2Br layer and the carbon electrode. A PCE of 14.03% is achieved by introducing BMIMBF4 which is improved by 23% compared with the control device (11.37%). Moreover, stability—whether in the case of C‐PSCs or CsPbI2Br films—is also improved. [ABSTRACT FROM AUTHOR]

In the past decade, organic–inorganic hybrid perovskite solar cells (PSCs) have begun to be increasingly studied worldwide owing to the superior properties of perovskite material. However, some issues have delayed their commercialization, such as their long‐term stability, cost reduction, scale‐up ability, and efficiency. The introduction of sulfur to PSCs can relieve the above issues because sulfur can passivate interfacial trap states, suppress charge recombination, and inhibit ion migration, thereby enhancing the stability of PSCs. Furthermore, PbS bonds provide new channels for carrier extraction. Herein, the sulfur‐based compounds utilized in PSCs are summarized and classified according to their functions in the different layers of PSCs. The results indicate that these sulfur‐based compounds have efficiently promoted the commercialization of PSCs. It is hoped that this review can help others understand the intrinsic phenomena of sulfur‐based PSCs and motivate additional investigations. [ABSTRACT FROM AUTHOR]

Benefiting from the high electrochemical surface area brought by the 2D nanosheet structure, MoS2 has received great research attention for the hydrogen evolution reaction (HER). Recently, it has been demonstrated that by constructing a transitional metal sulfide–MoS2 heterostructure, the HER performance of the MoS2-based catalysts can be further improved. It is even possible to obtain bifunctional catalysts for both HER and oxygen evolution reaction (OER) due to the synergistic effect of the different components in the composite, the electronic effect to enable an efficient electron transfer and appropriate binding energy for the intermediates of the electrocatalytic reactions, and the surface defects on the interface of the heterostructures. Herein, we review the recent progress on the construction of the transitional metal sulfide–MoS2 heterostructure for water splitting based on non-self-supporting and self-supporting catalysts. The surface and interface parameters of the heterostructures are discussed in detail to reveal the key roles of the hybrid structures for energy conversion. We also pay special attention to the theoretical simulations based on first principles to clarify the relationships between the electrochemical performance and structure parameters. Finally, the prospects and challenges of the transition metal sulfide–MoS2 heterostructures for water splitting in the future are proposed to prompt the reasonable design of transition metal sulfide–MoS2 heterostructures for full water splitting. [ABSTRACT FROM AUTHOR]

As an energy‐saving and environmentally friendly ammonia synthesis method, electrocatalytic nitrogen reduction reaction (NRR) has received a great deal of attention. There is thus an urgent need to find high‐efficiency electrocatalysts for the NRR. In this work, a Cu/Ti3C2 composite catalyst was prepared and demonstrated excellent selectivity under environmental conditions, which could efficiently convert N2 into NH3 electrochemically. In 0.1 M KOH, Cu/Ti3C2 can achieve a high Faradaic efficiency of 7.31 % and a high NH3 production rate of 3.04 μmol h−1 cm−2 at −0.5 V vs. RHE. Moreover, the material also exhibits superior electrochemical stability and durability. At the same time, density functional theory (DFT) shows that, compared with Ti3C2, Cu/Ti3C2 exhibits a wider conduction and valence band and a larger Fermi level, thus indicating that Cu plays a vital role in the enhancement of the catalytic activity and conductivity of Ti3C2‐based materials. This work provides a feasible strategy for designing high‐efficiency MXene‐based NRR electrocatalysts. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrogen reduction reaction (NRR), as a potential alternative to industrial ammonia synthesis (Haber‐Bosch method), can achieve "green" and sustainable ammonia production under environmental conditions. However, the NRR process is still limited by the slow cleavage of the N≡N triple bond and the existence of a competitive hydrogen evolution reaction. For this reason, many researchers have studied the construction and synthesis of high‐efficiency nitrogen reduction electrocatalysts. Herein, a Co‐based metal‐organic framework (ZIF‐67) was used to prepare Co/C‐900 composites through high‐temperature pyrolysis (900 °C) for ammonia synthesis under environmental conditions. The Co/C‐900 catalysts exhibited excellent NRR performance, with a high NH3 yield of 4.66 μmol cm−2 h−1 at −0.3 V (vs. RHE) and a faradaic efficiency of 11.53 % in 0.1 M potassium hydroxide. This work provides a simple strategy for the design of porous, non‐noble‐metal electrocatalysts for electrochemical NRR. [ABSTRACT FROM AUTHOR]

Low-cost and high-performance dye-sensitized solar cells (DSSCs) are considered promising candidates for commercial application. As one of the crucial components, electrolytes are considered the limiting factor for long-term DSSC stability. As alternative materials, solid-state electrolytes have been used in DSSCs, which may solve the problem of liquid electrolytes, such as leakage and volatilization. In this review, we define solid-state electrolytes as inorganic hole transport materials (HTMs), organic HTMs, ionic conductive polymer electrolytes, and ionic liquid polymer electrolytes according to the different types of carriers and summarize the latest development trends of these electrolytes. We discuss in detail the mechanism of solid-state dye-sensitized solar cells (ssDSSCs), including the hole transfer process at the dye/hole-conductor interface and factors that reduce the efficiency of ssDSSCs, and summarize several methods to improve the efficiency and long-term stability of ssDSSCs. These may facilitate the research and development of electrolytes for ssDSSCs. [ABSTRACT FROM AUTHOR]