Chandra, Christian Cahyadi, Handi Setiadi Alvin, Stevanus Devina, Winda Park, Jae-Ho Chang, Wonyoung Chung, Kyung Yoon Kwak, Sang Kyu Kim, Jaehoon 2024-01-19T18:30:37Z 2024-01-19T18:30:37Z 2021-09-05 2020-01-14 0897-4756 https://pubs.kist.re.kr/handle/201004/119089 Silicon oxycarbides (SiOCs) are considered promising anode materials for sodium-ion batteries. However, the mechanisms of Nation storage in SiOCs are not clear. In this study, the mechanism of Nation storage in high-temperature-synthesized SiOCs (1200-1400 degrees C) is examined. Phase separation of the oxygen (O)-rich and carbon (C)-rich SiOxCy domains of SiOC during synthesis was accompanied by the evolution of micropores, graphitic layers, and a silicon carbide (SiC) phase. The high-temperature-synthesized SiOCs exhibited a large voltage plateau capacity below 0.1 V (45-63% of the total capacity). Ex situ measurements and density functional theory simulations revealed that within the sloping voltage region, Nation uptake occurs mainly in the defects, micropores, C-rich SiOxCy phase, and some O-rich SiOxCy phases. In contrast, in the voltage plateau below 0.1 V, Na+-ion insertion into the O-rich SiOxCy phase and formation of Na-rich Si compounds are the main Nation uptake mechanisms. The generated SiC phase confers excellent long-term cyclability to the high-temperature-synthesized SiOxCy. English AMER CHEMICAL SOC HARD CARBON ANODES NA-ION BATTERIES HIGH-PERFORMANCE ANODE RICH SIOC ANODES AMORPHOUS-SILICON HIGH-CAPACITY ELECTROCHEMICAL PERFORMANCE LITHIUM STORAGE COMPOSITE ANODE STABLE ANODE Revealing the Sodium Storage Mechanism in High-Temperature-Synthesized Silicon Oxycarbides Article 10.1021/acs.chemmater.9b04018 1 CHEMISTRY OF MATERIALS, v.32, no.1, pp.410 - 423 CHEMISTRY OF MATERIALS 32 1 410 423 scie scopus 000507721600041 2-s2.0-85077464922 Chemistry, Physical Materials Science, Multidisciplinary Chemistry Materials Science Article HARD CARBON ANODES NA-ION BATTERIES HIGH-PERFORMANCE ANODE RICH SIOC ANODES AMORPHOUS-SILICON HIGH-CAPACITY ELECTROCHEMICAL PERFORMANCE LITHIUM STORAGE COMPOSITE ANODE STABLE ANODE