钒钨酸盐-CdS纳米粒子复合膜的制备与电致变色性能

通过层-层自组装方法制备了由Dawson结构三钒取代型钨酸盐1-K₉P₂W₁₅V₃O₆₂·18H₂O(P₂W₁₅V₃)与CdS纳米粒子构筑的复合膜材料, 研究了CdS纳米粒子添加和复合膜层数对P₂W₁₅V₃多酸复合膜材料电致变色性能的影响. 采用UV, XRD, SEM和循环伏安等测试手段对复合材料的结构和性能进行了表征; 将电化学工作站和紫外-可见吸收光谱联用, 在-1.0~+1.0 V的电压范围内, 对不同层数、 有无CdS纳米粒子复合的的膜材料的电致变色性能进行研究. 研究结果表明, 20层的复合膜材料性能最佳, 光反差为38.05%, 着色时间为3.57 s, 褪色时间为6.94 s, 最大着色效率达到94.04 cm²/C, 实现了从无色、 蓝色到蓝紫色, 再到无色的可逆颜色变化, 相对于单独P₂W₁₅V₃膜, 光反差提高46.07%, 着色效率提高96.53%, 电致变色性能显著提高.

Preparation and Properties of Vanadium Tungstate-CdS Nanoparticles Electrochromic Composite Films†

In order to study the effects of the addition of CdS nanoparticles and the number of composite film layers on the electrochromic properties of tri-vanadium substituted Dawson-type tungstate 1-K₉P₂W₁₅V₃O₆₂·18H₂O(P₂W₁₅V₃) polyoxometalate composite films, composite films constructed by P₂W₁₅V₃ and CdS nanoparticles were prepared by layer-by-layer self-assembly method. The structure and properties of the composite films were characterized by UV-Vis spectroscopy, XRD, SEM and cyclic voltammetry, and electrochemical workstation and UV-visible absorption spectroscopy were used to investigate the electrochromic properties of composite films with different layers and with or without CdS nanoparticles in the voltage range of -1.0—+1.0 V. The results show that the perfomanc of 20-layer composite film is the best, for which the optical contrast is 38.05%, response time for recolorstion and bleaching are 3.57 and 6.94 s, respectively, the maximum coloring efficiency is 94.04 cm²/C, compared with the P₂W₁₅V₃ film, the optical contrast increases by 46.07% and the color efficiency increases by 96.53%, the electrochromic performance is improved remarkably.