Quan Yiling, Hu Changhao, Feng Peifeng, Song Yujie, Liang Kun, Jian Xigao, Xu Jian
State Key Laboratory of Fine Chemicals, Liaoning High Performance Polymer Engineering Research Center, Department of Polymer Science and Materials, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.
Zhejiang Key Laboratory of Data-Driven High-Safety Energy Materials and Applications, Ningbo Key Laboratory of Special Energy Materials and Chemistry, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
Molecules. 2024 Sep 20;29(18):4461. doi: 10.3390/molecules29184461.
Polymer-derived silicon oxycarbide (SiOC) ceramics have garnered significant attention as novel silicon-based anode materials. However, the low conductivity of SiOC ceramics is a limiting factor, reducing both their rate capability and cycling stability. Therefore, controlling the free carbon content and its degree of graphitization within SiOC is crucial for determining battery performance. In this study, we regulated the free carbon content using divinylbenzene (DVB) and controlled the graphitization of free carbon with the transition metal iron (Fe). Through a simple pyrolysis process, we synthesized SiOC ceramic materials (CF) and investigated the impact of Fe-induced changes in the carbon phase and the amorphous SiOC phase on the comprehensive electrochemical performance. The results demonstrated that increasing the DVB content in the SiOC precursor enhanced the free carbon content, while the addition of Fe promoted the graphitization of free carbon and induced the formation of carbon nanotubes (CNTs). The electrochemical performance results showed that the CF electrode material exhibited a high reversible capacity of approximately 1154.05 mAh g at a low current density of 100 mA g and maintained good rate capability and cycling stability after 1000 cycles at a high current density of 2000 mA g.
聚合物衍生的碳氧化硅（SiOC）陶瓷作为新型硅基负极材料已受到广泛关注。然而，SiOC陶瓷的低电导率是一个限制因素，降低了其倍率性能和循环稳定性。因此，控制SiOC中的游离碳含量及其石墨化程度对于确定电池性能至关重要。在本研究中，我们使用二乙烯基苯（DVB）调节游离碳含量，并使用过渡金属铁（Fe）控制游离碳的石墨化。通过简单的热解过程，我们合成了SiOC陶瓷材料（CF），并研究了Fe诱导的碳相和非晶SiOC相变化对综合电化学性能的影响。结果表明，增加SiOC前驱体中的DVB含量可提高游离碳含量，而添加Fe则促进游离碳的石墨化并诱导形成碳纳米管（CNT）。电化学性能结果表明，CF电极材料在100 mA g的低电流密度下表现出约1154.05 mAh g的高可逆容量，在2000 mA g的高电流密度下经过1000次循环后仍保持良好的倍率性能和循环稳定性。
