EnergyChem最新文献

Electrochemical conversion is an eco-friendly and controllable way to achieve sustainable use of energy. An enhanced energy conversion efficiency requires efficient electrocatalysts to reduce the electrochemical energy barrier. The hollow structures, which have the advantage of optimizing mass/charge transfer, provide a platform for full contact between the electrocatalysts and the reactants, which has great potential for advanced electrocatalysts. In addition, rare earth-based materials integrate unique electronic configuration and chemical behavior into electrocatalysts, leading to improved performance and selectivity for various electrocatalysis. Combining hollow structures with rare earths is fascinating and challenging in terms of synthesis and electrocatalysis. This review expounds general synthesis methods of hollow structures with rare earths and then summarizes strategies to prepare highly efficient hollow electrocatalysts with rare earths.

Safety issues are the main obstacle that hinder the development of high-energy-density lithium batteries (LBs). Thermal runaway is the key scientific problem in the safety research of LBs. Recently, an ever-growing body of electrolytes are designed to improve the safety of LBs. Consequently, this review focuses on the thermal runaway behavior of LBs, including its inducement, process and the influence of electrolyte on it. Then, customized design of electrolytes are respectively proposed and discussed in order to deal with the inducement, chain exothermic reactions, fire and explosion during the three stages of thermal runaway. It is hoped this review can draw attention to the customized design of electrolytes, and thus promoting the development of high-safety and high-energy-density LBs.

Green hydrogen produced by water electrolysis is one of the most promising technologies to realize the efficient utilization of intermittent renewable energy and the decarbonizing future. Among various electrolysis technologies, the emerging anion-exchange membrane water electrolysis (AEMWE) shows the most potential for producing green hydrogen at a competitive price. In this review, we demonstrate a comprehensive introduction to AEMWE including the advanced electrode design, the lab-scaled testing system establishment, and the electrochemical performance evaluation. Specifically, recent progress in developing high activity transition metal-based powder electrocatalysts and self-supporting electrodes for AEMWE is summarized. To improve the synergistic transfer behaviors between electron, charge, water, and gas inside the gas diffusion electrode (GDE), two optimizing strategies are concluded by regulating the pore structure and interfacial chemistry. Moreover, we provide a detailed guideline for establishing the AEMWE testing system and selecting the electrolyzer components. The influences of the membrane electrode assembly (MEA) technologies and operation conditions on cell performance are also discussed. Besides, diverse electrochemical methods to evaluate the activity and stability, implement the failure analyses, and realize the in-situ characterizations are elaborated. In end, some perspectives about the optimization of interfacial environment and cost assessments have been proposed for the development of advanced and durable AEMWE.

Three-dimensionally ordered macroporous (3DOM) materials have aroused tremendous interest in solar light to energy conversion, sustainable and renewable products generation, and energy storage fields owing to their convenient mass transfer channels, high surface area, enhanced interaction between matter and light, plentiful reactive sites as well as tunable composition. In this review, the state-of-the-art 3DOM materials as well as their preparation methods and the relevant applications including photo/electrocatalytic sustainable energy conversion, solar cells, Li ion batteries and supercapacitor are thoroughly outlined. Meanwhile, the unique merits and mechanisms for 3DOM materials in various applications are revealed and discussed in depth. Moreover, the strategies for designing 3DOM materials and the enhanced performance for applications are correlated, which can be significantly valuable to help readers to promptly acquire the comprehensive knowledge and to inspire some new ideas in developing 3DOM materials for further improved performances. Finally, the challenges and perspectives of 3DOM materials for sustainable energy conversion/production, solar cells and energy storage fields are outlooked. We sincerely look forward to that this critical review can facilitate the fast developments in designing highly efficient 3DOM materials and the relevant applications.

Aqueous Zn metal batteries (AZBs) are considered as a promising candidate of existing lithium-ion batteries for grid-scale energy storage systems owing to their inherent safety, low cost, and natural abundance. However, the practical application of AZBs is still limited by severe dendrites, corrosion, and hydrogen evolution on zinc (Zn) anode as well as the dissolution of most cathode materials. Although Zn metals are relatively stable in mildly acidic aqueous electrolytes even without solid-electrolyte interphase (SEI), the interfacial structure becomes more significant in resolving the afore-mentioned problems. Herein, we comprehensively review the latest progress on the artificial interfacial layers (AILs) for high performance and safe AZBs. Addressing the fundamentals and challenges of AZBs, the functionality and design of AILs will be introduced discussing the current development of surface modified interphase, electrolyte derived SEI, and cathode/electrolyte interphase. Advanced characterization and simulation methods are also summarized for comprehensive analysis on failure and mechanism of AILs. Finally, our perspectives into future research direction of AILs will be presented.

Pore space partition (PSP) concept is a synthetic design concept and can also serve as a structure analysis method useful for next-step synthetic planning and execution. PSP provides an integrated chemistry-topology-focused tool to design new materials platforms. While PSP is no less effective for making large-pore materials, the growing importance of small-molecule gas storage and separation for green-energy applications provides impetus for developing small-pore materials for which the PSP strategy is uniquely suited. Currently, the best embodiment of the PSP concept is the partitioned-acs (pacs) platform in which both fine or coarse adjustments to the building blocks have sparked a transformation of a prototype framework into a huge and continuously expanding family of chemically robust materials with controllable pore metrics and functionalities suitable for tailored applications. The pacs compositional diversity results from the platform's intrinsic multi-module nature, geometric flexibility and tolerance towards individual module variations, and mutual structure-directing effects among various modules, all of which combine to enable the molecular-level uniform co-assemblies of chemical components rarely seen together elsewhere. In this contribution, we present an overview of different pore space engineering methods and how different MOF materials have contributed to important advances in chemical stability, industrial gas storage and gas separation. In particular, we will focus on synthetic assembly of the pacs system, highlighting the differences of pacs materials from other MOF platforms and advantages of pacs materials in enhancing various MOF properties.

Membrane separation technology is of great research interest in industry owing to its unparalleled merits such as high selectivity with unsuppressed permeability, reduced carbon footprint, small capital investment, and low energy consumption in comparison to traditional separation techniques. In the last few decades, polyamide membranes dominate the membrane industry until the porous organic polymers (POPs) get a ticket into the area of membrane separation. POPs bearing rich pore architectures and feasible functionalization are ready for fabricating novel membranes for rapid and precise molecular sieving. Here, a background overview of separation technology is provided, followed by a brief introduction of various POP-based membranes and the fabrication approaches of these membranes. Then, recent advancements of POP-bases membranes in energy-saving applications including gas separation and liquid separation are highlighted together with discussions about membrane design and generation involved. Finally, a concise conclusion with our perspective and challenges remaining for the future development of POP-based membranes are outlined.

Photocatalysis has been widely studied because it can use inexhaustible solar energy as an energy source while solving the problems of fossil fuel depletion and environmental pollution facing the 21st century. Metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), with many advantages such as high physical/chemical stability, tunable bandgap, structural diversity, large specific surface area, etc., are considered important propellants for building better photocatalytic platforms and achieving breakthroughs. This review outlines the applications of MOFs and COFs for photocatalysis in CO₂ reduction, H₂ generation, and environmental pollution treatment, and elucidates the relevant photocatalytic mechanisms. In particular, the methods and mechanisms for improving the photocatalytic performance of MOFs and COFs are summarized and discussed from the three aspects. Finally, the current limitations, challenges, perspectives and future development opportunities of COFs/MOFs and COF-/MOF-based photocatalysts are summarized and prospected.

The development of future energy devices that exhibit high safety, sustainability, and high energy densities to replace the currently dominant lithium-ion batteries has gained significant attention in recent years. Although the various energy devices available have different technological requirements, electrolyte formulation still remains a fundamental element of these state-of-the-art systems. Among the trending electrolyte contenders, ionic liquids, which are entirely comprised of cations and anions, provide a combination of several unique physicochemical and electrochemical properties, and exceptional safety. In this review, the fundamental properties of IL, their progress and milestones, and the directions for their future development and applications in next-generation energy devices are summarized. Each section will comprehensively review the latest progress and technology trends utilizing IL electrolytes focusing on Li-, Na-, K-ion batteries, metal anode batteries, sulfur and oxygen batteries, multivalent metal-ion batteries, and supercapacitors, with early studies mentioned where relevant. The benefits of using ionic liquid electrolytes on each system and pertinent improvements in performance are delineated in comparison to systems utilizing conventional electrolytes. Finally, prospects and challenges associated with the applications of ionic liquid electrolytes to future energy devices are also discussed.