Dae–Kwon Boo , Huiju Kim , Seung Jae Kwak , Ho–Jin Lee , Yeji Lim , Yoonjeong Yoo , Hyechan Park , Junhyuk Tak , Ji Hyun Lee , Jae–Woo Seo , Seon–Jin Choi , Ki Ro Yoon , Wonchang Choi , Bonjae Koo , Won Bo Lee , YongJoo Kim , Won–Hee Ryu , Ji–Won Jung
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引用次数: 0
Abstract
Lithium–carbon dioxide (Li–CO2) batteries utilize a lightweight and environmentally impactful CO2 gas as a cathode and offer a high energy density (1876 Wh kg−1). However, the thermodynamically stable discharge product, Li2CO3, necessitates the use of catalysts to facilitate reversible reaction kinetics, underscoring the importance of developing efficient catalysts to overcome this bottleneck. In this study, we fabricate nanofiber NiO–RuO2 composite oxide catalysts (nf–NRO) to utilize the synergistic effect of the two oxides. In particular, we spotlight a critical phenomenon–rivalrous grain growth between two oxide components–as a strategy for catalyst optimization, balancing cost–effectiveness and catalytic performance. We observe rivalrous particle size changing behavior, where increasing the RuO2 ratio in the composite oxide leads to RuO2 downsizing and NiO coarsening. To elucidate this phenomenon, we propose expected mechanisms supported by DFT calculations; 1) Band bending between metallic oxide and p–type semiconductor, 2) Interfacial redox reactions driven by differences in the reduction potentials of the NiO and RuO2 nanoparticles, 3) Acceleration of NiO growth due to the oxygen donor effect of RuO2 coupled with surface energy–driven growth mechanisms. Accordingly, the catalytic property of nf–NRO55 is maximized by downsizing RuO2 and Ni3+–rich NiO. The Li–CO2 battery with nf–NRO exhibits lower charge platform and superior cycle stability over 120 cycles. As a result, the correlation between the material properties of the nf–NRO and their electrochemical performance is identified.
期刊介绍:
Composites Part B: Engineering is a journal that publishes impactful research of high quality on composite materials. This research is supported by fundamental mechanics and materials science and engineering approaches. The targeted research can cover a wide range of length scales, ranging from nano to micro and meso, and even to the full product and structure level. The journal specifically focuses on engineering applications that involve high performance composites. These applications can range from low volume and high cost to high volume and low cost composite development.
The main goal of the journal is to provide a platform for the prompt publication of original and high quality research. The emphasis is on design, development, modeling, validation, and manufacturing of engineering details and concepts. The journal welcomes both basic research papers and proposals for review articles. Authors are encouraged to address challenges across various application areas. These areas include, but are not limited to, aerospace, automotive, and other surface transportation. The journal also covers energy-related applications, with a focus on renewable energy. Other application areas include infrastructure, off-shore and maritime projects, health care technology, and recreational products.