Qi Yang , Yunfei Wu , Hui Feng , Haigang Liu , Xiaobing Lou , Menghui Jia , Xinhai Wu , Wen Wen , Bingwen Hu
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引用次数: 0
Abstract
Li-CO2/O2 batteries present a promising strategy for CO2 conversion and energy storage, yet the complexity of discharge products poses challenges for revealing their oxidation. Here, we simulate the influences of various properties of Li2CO3 and/or Li2O2 on the decomposition pathway by comprehensively analyzing the singlet O2 (1O2) and gas components (O2 and CO2) generated during electrochemical oxidation. Our results show that no matter Li2CO3 or Li2O2, the decomposition of samples with small size and poor crystallinity produces less 1O2 and more gas product. Especially, small and poorly crystalline Li2CO3 triggers the concurrent decomposition of Li2CO3 and C, while large and highly crystalline Li2CO3 favors the solo decomposition pathway. Furthermore, the 1O2 yield can be most inhibited at a Li2CO3/Li2O2 ratio of 50 %. After clarifying the nature of Li2CO3 and/or Li2O2 oxidation, the spatial distributions of the oxygen discharge product in Li-CO2/O2 batteries were observed by scanning transmission X-ray microscopy (STXM). Li2CO3 is mainly distributed in the interior of large aggregates with high crystallinity. Poorly crystalline Li2O2 appears as small particles or coats on the surface of Li2CO3. Combined with multi-dimensional information of the discharge products and simulation results, the oxidation behaviors of the discharge products in Li-CO2/O2 batteries are reacquainted.
期刊介绍:
Energy Storage Materials is a global interdisciplinary journal dedicated to sharing scientific and technological advancements in materials and devices for advanced energy storage and related energy conversion, such as in metal-O2 batteries. The journal features comprehensive research articles, including full papers and short communications, as well as authoritative feature articles and reviews by leading experts in the field.
Energy Storage Materials covers a wide range of topics, including the synthesis, fabrication, structure, properties, performance, and technological applications of energy storage materials. Additionally, the journal explores strategies, policies, and developments in the field of energy storage materials and devices for sustainable energy.
Published papers are selected based on their scientific and technological significance, their ability to provide valuable new knowledge, and their relevance to the international research community.