Wang Shi-Ming, Jin Yuan-Hang, Zhou Lu, Wang Kai-Hua, Kim Hee Jung, Liu Lin, Kim Eunkyoung, Han Zhengbo
Light Industry College, Liaoning University, 66 Chongshan Middle Road, Huanggu District, Shenyang 110036, China.
Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea.
ACS Appl Mater Interfaces. 2023 Dec 6;15(48):56242-56252. doi: 10.1021/acsami.3c11948. Epub 2023 Nov 17.
A porous hydrogen-bonded organic framework (HOF) structure was explored for the first time in the design of high-performance electrochromic devices (ECDs) using polyoxometalate (POM)-based charge-balancing layers as counter electrodes (CEs). The novelty of this work lies in the facile construction of films using small molecule-based EC materials to form a porous HOF structure. A full-cell model of an ECD was constructed by utilizing a POM-based CE to optimize the voltage distribution on the HOF-coated working electrode (WE). The addition of PWO (PW) on CE significantly enhanced the voltage distribution on EC electrodes and decreased the overvoltage on the WE, further preventing the formation of non-EC species and resulting in a 3.3-fold increase in the lifetime of the ECD. The optical contrast was enhanced from 47% (TiO only) to 68%, and the coloration efficiency was enhanced from 185 (TiO only) to 373 cm C. The optimized voltage distribution on the WE, leading to the fast response time and high optical EC contrast, could be explained by the charge-balancing effect. Overall, this new finding provides a robust framework for designing high-performance ECDs, taking advantage of the porous morphology and potential matching of the HOF and PW.
在使用基于多金属氧酸盐（POM）的电荷平衡层作为对电极（CE）来设计高性能电致变色器件（ECD）的过程中，首次探索了一种多孔氢键有机框架（HOF）结构。这项工作的新颖之处在于使用基于小分子的电致变色材料轻松构建薄膜，以形成多孔HOF结构。通过利用基于POM的CE构建ECD的全电池模型，优化了涂覆HOF的工作电极（WE）上的电压分布。在CE上添加PWO（PW）显著增强了电致变色电极上的电压分布，并降低了WE上的过电压，进一步防止了非电致变色物种的形成，导致ECD的寿命增加了3.3倍。光学对比度从47%（仅TiO）提高到68%，着色效率从185（仅TiO）提高到373 cm C。WE上优化的电压分布导致了快速响应时间和高光电化学对比度，这可以通过电荷平衡效应来解释。总体而言，这一新发现利用HOF和PW的多孔形态及电位匹配，为设计高性能ECD提供了一个强大的框架。
