Liu Tianming, Lv Guocheng, Liu Meng, Cui Xiaoya, Liu Hao, Li Haodong, Zhao Changchun, Wang Longfei, Guo Juchen, Liao Libing
Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources, Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083, China.
School of Science, China University of Geosciences, Beijing 100083, China.
ACS Nano. 2024 Nov 12;18(45):31559-31568. doi: 10.1021/acsnano.4c13092. Epub 2024 Oct 30.
Aluminum-sulfur batteries (ASBs) are emerging as promising energy storage systems due to their safety, low cost, and high theoretical capacity. However, it remains a challenge to overcome voltage hysteresis and short cycle life in the sulfur/AlS conversion reaction, which hinders the development of ASBs. Here, we studied a high-voltage ASB system based on sulfur oxidation in an AlCl/urea electrolyte. Nitrogen-doped hollow nanocages (HNCs) synthesized from MOF precursors were rationally designed as sulfur/carbon composite electrodes (S@HNC), and the impact of the nitrogen species on the electrochemical performance of sulfur electrodes was systematically investigated. The S@HNC-900 achieved efficient conversion at 1.9 V, delivering a stable capacity of 197.3 mA h g and a Coulombic efficiency of 93.28% after 100 cycles. Furthermore, the S@HNC-900 electrode exhibited exceptional rate capacity and 800th long-term cycling stability, retaining a capacity of 87.1 mA h g at 500 mA g. Ex situ XPS and XRD characterizations elucidated the redox mechanism, revealing a four-electron transfer process (S/AlSCl) at the S@HNC-900 electrode. Density functional theory calculations demonstrated that pyridinic nitrogen-enriched HNC-900 significantly enhanced the sulfur conversion reaction and facilitated the adsorption of sulfur intermediates (SCl) on the carbon interface. This work provides critical insights into the high-voltage sulfur redox mechanism and establishes a foundation for the rational design of carbon-based electrocatalysts for the enhancement of ASB performance.
铝硫电池（ASB）因其安全性、低成本和高理论容量而成为有前景的储能系统。然而，克服硫/AlS转化反应中的电压滞后和短循环寿命仍是一项挑战，这阻碍了铝硫电池的发展。在此，我们研究了一种基于AlCl/尿素电解液中硫氧化的高压铝硫电池系统。由金属有机框架（MOF）前驱体合成的氮掺杂空心纳米笼（HNC）被合理设计为硫/碳复合电极（S@HNC），并系统研究了氮物种对硫电极电化学性能的影响。S@HNC - 900在1.9 V时实现了高效转化，100次循环后提供了197.3 mA h g的稳定容量和93.28%的库仑效率。此外，S@HNC - 900电极表现出优异的倍率性能和800次长期循环稳定性，在500 mA g时保持87.1 mA h g的容量。非原位X射线光电子能谱（XPS）和X射线衍射（XRD）表征阐明了氧化还原机理，揭示了S@HNC - 900电极处的四电子转移过程（S/AlSCl）。密度泛函理论计算表明，富含吡啶氮的HNC - 900显著增强了硫转化反应，并促进了硫中间体（SCl）在碳界面上的吸附。这项工作为高压硫氧化还原机理提供了关键见解，并为合理设计用于提高铝硫电池性能的碳基电催化剂奠定了基础。
