Electrodeposition of Ti-Doped Hierarchically Mesoporous Silica Microspheres/Tungsten Oxide Nanocrystallines Hybrid Films and Their Electrochromic Performance

Abstract

In this paper, a novel Ti-doped hierarchically mesoporous silica microspheres/tungsten oxide (THMS/WO3) hybrid film was prepared by simultaneous electrodeposition of Ti-doped hierarchically mesoporous silica microspheres (THMSs) and WO3 nanocrystallines onto the fluoride doped tin dioxide (FTO) coated glass substrate. It is demonstrated that the incorporation of THMSs resulted in the hybrid film with improved electrochromic property. Besides, the content of THMSs plays an important role on the electrochromic property of the hybrid film. An excellent electrochromic THMS/WO3 hybrid film with good optical modulation (52.00% at 700 nm), high coloration efficiency (88.84 cm2 C−1 at 700 nm), and superior cycling stability can be prepared by keeping the weight ratio of Na2WO4·2H2O (precursor of WO3):THMSs at 15:1. The outstanding electrochromic performances of the THMS/WO3 hybrid film were mainly attributed to the porous structure, which facilitates the charge-transfer, promotes the electrolyte infiltration and alleviates the expansion of the film during Li+ insertion. This kind of porous THMS/WO3 hybrid film is promising for a wide range of applications in smart homes, green buildings, airplanes, and automobiles.

Review on recent progress in WO3-based electrochromic films: preparation methods and performance enhancement strategies

“…To meet the requirements of the new generation of ECDs, researchers have explored a number of strategies such as constructing nanostructure, 29,30,122–125 regulating crystallinity, 32,34,62 doping modification, 17,126 designing composite structure, 127,128 and using suitable electrolyte ion dosage, 129 which can effectively improve the EC performance of WO 3 films.…”

Growth behavior of WO₃crystal topological structure and its electrochromic properties

“…当无草酸时, 生成针状结构, 针状与针状之间 没有"黏合剂"存在, 故独立生长成为由纳米针组成 的海胆状晶体拓扑结构. 而有草酸时, 则有"黏合 剂"存在, 生成的纳米针相互黏合, 形成花瓣片状 结构, 最终组合为花朵状的WO 3 晶体拓扑结构 [32] . 理论计算得到微米花比表面积约为16.84 m 2 /g.…”

Highly stable electrochromic cells based on amorphous tungsten oxides prepared using a solution‐annealing process

“…Numerous methods have been being carried out to prepare electrochromic WO 3 electronic devices, and different approaches have been being employed to boost the efficiency of devices to prepare practical, commercial, and friendly enviroment devices. Various methods such as the hydrothermal method, 25,26 chemical vapor deposition, 27,28 thermal evaporation, 29,30 sputtering, 31,32 sol-gel method, 33,34 and electrochemical deposition 35,36 have been used to prepare electrochromic tungsten oxide films and the electrochromic performance of tungsten oxide films with different morphologies such as amorphous films, 37,38 crystalline films, 39 nanoparticle films, 40,41 nanowire films, 42 or nanorod films. 43,44 However, these methods present several disadvantages such as the use of expensive equipment, toxic environment, or complicated processing.…”