Ronan Oskar, Roy Ahin, Ryan Sean, Hughes Lucia, Downing Clive, Jones Lewys, Nicolosi Valeria
Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and Advanced Materials and Bioengineering Research (AMBER), School of Chemistry, Trinity College Dublin, DublinDublin 2, Ireland.
Materials Science Centre, Indian Institute of Technology, Kharagpur721302, West Bengal, India.
ACS Omega. 2022 Dec 28;8(1):925-933. doi: 10.1021/acsomega.2c06298. eCollection 2023 Jan 10.
One of the weaknesses of silicon-based batteries is the rapid deterioration of the charge-storage capacity with increasing cycle numbers. Pure silicon anodes tend to suffer from poor cycling ability due to the pulverization of the crystal structure after repeated charge and discharge cycles. In this work, we present the synthesis of a hollow nanostructured SiO material for lithium-ion anode applications to counter this drawback. To improve the understanding of the synthesis route, the crucial synthesis step of removing the ZnO template core is shown using an in situ closed gas-cell sample holder for transmission electron microscopy. A direct visual observation of the removal of the ZnO template from the SiO shell is yet to be reported in the literature and is a critical step in understanding the mechanism by which these hollow nanostructures form from their core-shell precursors for future electrode material design. Using this unique technique, observation of dynamic phenomena at the individual particle scale is possible with simultaneous heating in a reactive gas environment. The electrochemical benefits of the hollow morphology are demonstrated with exceptional cycling performance, with capacity increasing with subsequent charge-discharge cycles. This demonstrates the criticality of nanostructured battery materials for the development of next-generation Li-ion batteries.
硅基电池的一个弱点是随着循环次数的增加，其电荷存储容量会迅速下降。由于在反复的充放电循环后晶体结构会发生粉碎，纯硅阳极往往具有较差的循环能力。在这项工作中，我们展示了一种用于锂离子阳极应用的中空纳米结构SiO材料的合成方法，以克服这一缺点。为了更好地理解合成路线，使用用于透射电子显微镜的原位封闭气室样品架展示了去除ZnO模板核的关键合成步骤。从SiO壳中去除ZnO模板的直接视觉观察在文献中尚未见报道，这是理解这些中空纳米结构如何从其核壳前驱体形成的机制的关键步骤，对未来电极材料设计具有重要意义。使用这种独特的技术，可以在反应性气体环境中同时加热的情况下，在单个颗粒尺度上观察动态现象。中空形态的电化学优势通过出色的循环性能得到了证明，随着后续充放电循环，容量不断增加。这证明了纳米结构电池材料对下一代锂离子电池发展的至关重要性。
