能源化学最新文献

The discovery of efficient, selective, and stable electrocatalysts can be a key point to produce the large-scale chemical fuels via electrochemical CO₂ reduction (ECR). In this study, an earth-abundant and nontoxic ZnO-based electrocatalyst was developed for use in gas-diffusion electrodes (GDE), and the effect of nitrogen (N) doping on the ECR activity of ZnO electrocatalysts was investigated. Initially, a ZnO nanosheet was prepared via the hydrothermal method, and nitridation was performed at different times to control the N-doping content. With an increase in the N-doping content, the morphological properties of the nanosheet changed significantly, namely, the 2D nanosheets transformed into irregularly shaped nanoparticles. Furthermore, the ECR performance of ZnO electrocatalysts with different N-doping content was assessed in 1.0 M KHCO₃ electrolyte using a gas-diffusion electrode-based ECR cell. While the ECR activity increased after a small amount of N doping, it decreased for higher N doping content. Among them, the N:ZnO-1 h electrocatalysts showed the best CO selectivity, with a faradaic efficiency (FE_CO) of 92.7% at −0.73 V vs. reversible hydrogen electrode (RHE), which was greater than that of an undoped ZnO electrocatalyst (FE_CO of 63.4% at −0.78 V_RHE). Also, the N:ZnO-1 h electrocatalyst exhibited outstanding durability for 16 h, with a partial current density of −92.1 mA cm⁻². This improvement of N:ZnO-1 h electrocatalyst can be explained by density functional theory calculations, demonstrating that this improvement of N:ZnO-1 h electrocatalyst comes from (i) the optimized active sites lowering the free energy barrier for the rate-determining step (RDS), and (ii) the modification of electronic structure enhancing the electron transfer rate by N doping.

In the scope of developing new electrochemical concepts to build batteries with high energy density, chloride ion batteries (CIBs) have emerged as a candidate for the next generation of novel electrochemical energy storage technologies, which show the potential in matching or even surpassing the current lithium metal batteries in terms of energy density, dendrite-free safety, and elimination of the dependence on the strained lithium and cobalt resources. However, the development of CIBs is still at the initial stage with unsatisfactory performance and several challenges have hindered them from reaching commercialization. In this review, we examine the current advances of CIBs by considering the electrode material design to the electrolyte, thus outlining the new opportunities of aqueous CIBs especially combined with desalination, chloride redox battery, etc. With respect to the developing road of lithium ion and fluoride ion batteries, the possibility of using solid-state chloride ion conductors to replace liquid electrolytes is tentatively discussed. Going beyond, perspectives and clear suggestions are concluded by highlighting the major obstacles and by prescribing specific research topics to inspire more efforts for CIBs in large-scale energy storage applications.

Perovskite solar cell has gained widespread attention as a promising technology for renewable energy. However, their commercial viability has been hampered by their long-term stability and potential Pb leakage. Herein, we demonstrate a bifunctional passivator of the potassium tartrate (PT) to address both challenges. PT minimizes the Pb leakage in perovskites and also heals cationic vacancy defects, resulting in improved device performance and stability. Benefiting from PT modification, the power conversion efficiency (PCE) is improved to 23.26% and the Pb leakage in unencapsulated films is significantly reduced to 9.79 ppm. Furthermore, the corresponding device exhibits no significant decay in PCE after tracking at the maximum power point (MPP) for 2000 h under illumination (LED source, 100 mW cm⁻²).

The electrochemical methanol oxidation is a crucial reaction in the conversion of renewable energy. To enable the widespread adoption of direct methanol fuel cells (DMFCs), it is essential to create and engineer catalysts that are both highly effective and robust for conducting the methanol oxidation reaction (MOR). In this work, trimetallic PtCoRu electrocatalysts on nitrogen-doped carbon and multi-wall carbon nanotubes (PtCoRu@NC/MWCNTs) were prepared through a two-pot synthetic strategy. The acceleration of CO oxidation to CO₂ and the blocking of CO reduction on adjacent Pt active sites were attributed to the crucial role played by cobalt atoms in the as-prepared electrocatalysts. The precise control of Co atoms loading was achieved through precursor stoichiometry. Various physicochemical techniques were employed to analyze the morphology, element composition, and electronic state of the catalyst. Electrochemical investigations and theoretical calculations confirmed that the Pt₁Co₃Ru₁@NC/MWCNTs exhibit excellent electrocatalytic performance and durability for the process of MOR. The enhanced MOR activity can be attributed to the synergistic effect between the multiple elements resulting from precisely controlled Co loading content on surface of the electrocatalyst, which facilitates efficient charge transfer. This interaction between the multiple components also modifies the electronic structures of active sites, thereby promoting the conversion of intermediates and accelerating the MOR process. Thus, achieving precise control over Co loading in PtCoRu@NC/MWCNTs would enable the development of high-performance catalysts for DMFCs.

PrBa_0.5Sr_0.5Co_1.5Fe_0.5O_5+δ (PrBSCF) has attracted much research interest as a potential triple ionic and electronic conductor (TIEC) electrode for protonic ceramic fuel cells (PCFCs). The chemical formula for PrBSCF is AA’B₂O_5+δ, with Pr (A-site) and Ba/Sr (A’-site) alternately stacked along the c-axis. Due to these structural features, the bulk oxygen ion diffusivity is significantly enhanced through the disorder-free channels in the PrO layer; thus, the A site cations (lanthanide ions) play a pivotal role in determining the overall electrochemical properties of layered perovskites. Consequently, previous research has predominantly focused on the electrical properties and oxygen bulk/surface kinetics of Ln cation effects, whereas the hydration properties for PCFC systems remain unidentified. Here, we thoroughly examined the proton uptake behavior and thermodynamic parameters for the hydration reaction to conclusively determine the changes in the electrochemical performances depending on LnBa_0.5Sr_0.5Co_1.5Fe_0.5O_5+δ (LnBSCF, Ln=Pr, Nd, and Gd) cathodes. At 500 °C, the quantitative proton concentration of PrBSCF was 2.04 mol% and progressively decreased as the Ln cation size decreased. Similarly, the Gibbs free energy indicated that less energy was required for the formation of protonic defects in the order of PrBSCF < NdBSCF < GdBSCF. To elucidate the close relationship between hydration properties and electrochemical performances in LnBSCF cathodes, PCFC single cell measurements and analysis of the distribution of relaxation time were further investigated.

The recent emergence of tetragonal phases zirconium dioxide (ZrO₂) with vacancies has generated significant interest as a highly efficient and stable electrocatalyst with potential applications in trapping polysulfides and facilitating rapid conversion in lithium-sulfur batteries (LSBs). However, the reduction of ZrO₂ is challenging, even under strong reducing atmospheres at high temperatures and pressures. Consequently, the limited presence of oxygen vacancies results in insufficient active sites and reaction interfaces, thereby hindering practical implementation. Herein, we successfully introduced abundant oxygen vacancies into ZrO₂ at the nanoscale with the help of carbon nanotubes (CNTs-OH) through hydrogen-etching at lower temperatures and pressures. The introduced oxygen vacancies on ZrO_2−x/CNTs-OH can effectively rearrange charge distribution, enhance sulfiphilicity and increase active sites, contributing to high ionic and electronic transfer kinetics, strong binding energy and low redox barriers between polysulfides and ZrO_2−x. These findings have been experimentally validated and supported by theory calculations. As a result, LSBs assembled with the ZrO_2−x/CNTs-OH modified separators demonstrate excellent rate performance, superior cycling stability, and ultra-high sulfur utilization. Especially, at high sulfur loading of 6 mg cm⁻², the area capacity is still up to 6.3 mA h cm⁻². This work provides valuable insights into the structural and functional optimization of electrocatalysts for batteries.

Zinc-ion batteries (ZIBs) are considered to be one of the most promising candidates to replace lithium-ion batteries (LIBs) due to the high theoretical capacity, low cost and intrinsic safety. However, zinc dendrites, hydrogen evolution reaction, surface passivation and other side reactions will inevitably occur during the charging and discharging process of Zn anode, which will seriously affect the cycle stability of the battery and hinder its practical application. The etching strategy of Zn anode has attracted wide attention because of its simple operation and broad commercial prospects, and the etched Zn anode can effectively improve its electrochemical performance. However, there is no comprehensive review of the etching strategy of Zn anode. This review first summarizes the challenges faced by Zn anode, then puts forward the etching mechanisms and properties of acid, salt and other etchants. Finally, based on the above discussion, the challenges and opportunities of Zn anode etching strategy are proposed.

Solid-state electrolyte Li₁₀GeP₂S₁₂ (LGPS) has a high lithium ion conductivity of 12 mS cm⁻¹ at room temperature, but its inferior chemical stability against lithium metal anode impedes its practical application. Among all solutions, Ge atom substitution of the solid-state electrolyte LGPS stands out as the most promising solution to this interface problem. A systematic screening framework for Ge atom substitution including ionic conductivity, thermodynamic stability, electronic and mechanical properties is utilized to solve it. For fast screening, an enhanced model DopNetFC using chemical formulas for the dataset is adopted to predict ionic conductivity. Finally, Li₁₀SrP₂S₁₂ (LSrPS) is screened out, which has high lithium ion conductivity (12.58 mS cm⁻¹). In addition, an enhanced migration of lithium ion across the LSrPS/Li interface is found. Meanwhile, compared to the LGPS/Li interface, LSrPS/Li interface exhibits a larger Schottky barrier (0.134 eV), smaller electron transfer region (3.103 Å), and enhanced ability to block additional electrons, all of which contribute to the stabilized interface. The applied theoretical atom substitution screening framework with the aid of machine learning can be extended to rapid determination of modified specific material schemes.

The electrochemical carbon dioxide reduction reaction (eCO₂RR), which converts CO₂ into various hydrocarbons or alcohols, has been extensively researched because it promises a sustainable energy economy. However, only copper (Cu) can currently achieve stable and efficient hydrocarbon conversion in the eCO₂RR. Therefore, understanding the catalytic mechanisms and summarizing the research progress on synthesis strategies of Cu catalysts are essential for the eCO₂RR. This paper reviews Cu catalysts with different surface states of Cu catalysts: oxide-derived Cu, Cu nanoparticles, Cu single atoms, and Cu nanoclusters. It then reviews the development and progress of different Cu-catalyst preparation methods in recent years, focusing on the activity and selectivity of materials. Besides revealing the tendencies of catalytic selection and deep reactive mechanisms of Cu catalysts with four different surface states, this review can guide the subsequent construction of catalysts and provides an understanding of catalytic mechanisms.

While newer, more efficient Lithium-ion batteries (LIBs) and extinguishing agents have been developed to reduce the occurrence of thermal runaway accidents, there is still a scarcity of research focused on the application of surfactants in different LIBs extinguishing agents, particularly in terms of patented technologies. The aim of this review paper is to provide an overview of the technological progress of LIBs and LIBs extinguishing agents in terms of patents in Korea, Japan, Europe, the United States, China, etc. The initial part of this review paper is sort out LIBs technology development in different regions. In addition, to compare LIBs extinguishing agent progress and challenges of liquid, solid, combination of multiple, and microencapsulated. The subsequent section of this review focuses on an in-depth analysis dedicated to the efficiency and challenges faced by the surfactants corresponding design principles of LIBs extinguishing agents, such as nonionic and anionic surfactants. A total of 451,760 LIBs-related patent and 20 LIBs-fire-extinguishing agent-related patent were included in the analyses. The extinguishing effect, cooling performance, and anti-recombustion on different agents have been highlighted. After a comprehensive comparison of these agents, this review suggests that temperature-sensitive hydrogel extinguishing agent is ideal for the effective control of LIBs fire. The progress and challenges of surfactants have been extensively examined, focusing on key factors such as surface activity, thermal stability, foaming properties, environmental friendliness, and electrical conductivity. Moreover, it is crucial to emphasize that the selection of a suitable surfactant must align with the extinguishing strategy of the extinguishing agent for optimal firefighting effectiveness.