Li Hua, Tang Zijuan, Liu Yuwei, Robichaud Jacques, Liang Jian, Jiang Weihui, Djaoued Yahia
Department of Materials Chemistry, School of Materials Science and Engineering, Jingdezhen Ceramic University, Jingdezhen 333403, China.
Laboratoire de Recherche en Matériaux et Micro-Spectroscopies Raman et FTIR, Université de Moncton-Campus de Shippagan, Shippagan, NB E8S1P6, Canada.
Materials (Basel). 2022 Apr 15;15(8):2904. doi: 10.3390/ma15082904.
The open-layered structure of Vanadium pentoxide (VO) has triggered significant interest in exploring its energy-related application as lithium (Li) intercalation cathode material. Various methods are extensively studied to improve the Li diffusion using thin films or nanoarchitecture. In this work, high-quality two-dimensional (2D) inverse opal α-VO films were synthesized via a modified 'dynamic hard template' infiltration strategy using sacrificial polystyrene spheres (PS, a diameter of 530 nm) photonic crystal as a template. The new material exhibited an excellent porous array with featured structural colors in a large area. The electrochromic behavior was explored by combining bandgap and electrochemical characterization. On the one hand, the intercalation/deintercalation of Li played an important role in the bandgap (Eg), and thereafter on the visible range transmittance through changing the film's stoichiometry and the valence of vanadium ions. On the other hand, the asymmetry of the lattice due to the disordered distribution of Li within the VO interlayer and/or the formation of an irreversible phase explained the change in transmittance with voltage.
五氧化二钒（VO）的开放层状结构引发了人们对将其作为锂（Li）嵌入阴极材料探索其能源相关应用的浓厚兴趣。人们广泛研究了各种方法，利用薄膜或纳米结构来改善锂的扩散。在这项工作中，通过一种改进的“动态硬模板”浸润策略，以牺牲聚苯乙烯球体（PS，直径530纳米）光子晶体为模板，合成了高质量的二维（2D）反蛋白石α-VO薄膜。这种新材料展现出优异的多孔阵列，并在大面积上具有独特的结构颜色。通过结合带隙和电化学表征来探索其电致变色行为。一方面，锂的嵌入/脱嵌在带隙（Eg）中起重要作用，进而通过改变薄膜的化学计量比和钒离子的价态影响可见光范围内的透过率。另一方面，由于锂在VO层间分布无序导致的晶格不对称和/或不可逆相的形成解释了透过率随电压的变化。
