高度エネルギーデバイスに向けたメソ細孔有する層状ナノ物質の創製

在JSPS的最后一年，我们专注于三明治结构的有序介孔多巴胺/MXene杂化材料。有机聚合物由于具有分子柔性、成本效益和环境友好等优点，作为储能设备的电极材料引起了人们极大的兴趣。然而，聚合物基电极的稳定性差、容量低、电子转移/离子扩散动力学慢等限制了其真正的应用。本文以PS-b-PEO嵌段聚合物为软模板，通过多巴胺在Ti3C2Tx表面的原位聚合，制备了有序介孔多巴胺/Ti3C2Tx的三明治结构复合材料。具有垂直取向、可接近的纳米孔(约20 nm)的OMPDA层为离子扩散提供了连续的孔道，而Ti3C2Tx层保证了快速的电子转移路径。作为潜在的应用之一，OMPDA/Ti3C2Tx复合负极具有高的可逆容量、良好的倍率性能和优异的锂离子电池循环性能。原位电子显微镜分析表明，复合材料中的OMPDA仅表现出较小的体积膨胀，并且在锂化过程中几乎保持了初始形态，这一发现将为解决2D材料重新堆叠的挑战提供宝贵的知识，有助于确定最有前途的结构，并进一步提高2D材料的电化学性能。

In the last year of this JSPS, we focused on sandwich-structured ordered mesoporous polydopamine/MXene hybrids. Organic polymers have attracted significant interest as electrodes for energy storage devices because of their advantages, including molecular flexibility, cost-effectiveness, and environmentally friendly nature. Nevertheless, the real implementation of polymer-based electrodes is restricted by their poor stability, low capacity, and slow electron-transfer/ion diffusion kinetics. Herein, a sandwich-structured composite of ordered mesoporous polydopamine (OMPDA)/Ti3C2Tx was fabricated by in situ polymerization of dopamine on the surface of Ti3C2Tx via employing the PS-b-PEO block polymer as a soft template. The OMPDA layers with vertically oriented, accessible nanopores (around 20 nm) provided a continuous pore channel for ion diffusion, while the Ti3C2Tx layers guaranteed a fast electron-transfer path. As one of the potential applications, the OMPDA/Ti3C2Tx composite anode exhibited high reversible capacity, good rate performance, and excellent cyclability for lithium-ion batteries. The in situ transmission electron microscopy analysis revealed that the OMPDA in the composite only showed a small volume expansion and almost preserved the initial morphology during lithiation.This finding will provide valuable knowledge to tackle the challenges of the restacking of 2D materials, help to identify the most promising architecture and further improve the electrochemical performance of 2D materials.