State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, China.
Nanoscale. 2015 Oct 28;7(40):17088-95. doi: 10.1039/c5nr04458h. Epub 2015 Sep 30.
Electrochromic materials are the most important and essential components in an electrochromic device. Herein, we fabricated high-performance electrochromic films based on exfoliated layered double hydroxide (LDH) nanosheets and Prussian blue (PB) nanoparticles via the layer-by-layer assembly technique. X-ray diffraction and UV-vis absorption spectroscopy indicate a periodic layered structure with uniform and regular growth of (LDH/PB)n ultrathin films (UTFs). The resulting (LDH/PB)n UTF electrodes exhibit electrochromic behavior arising from the reversible K(+) ion migration into/out of the PB lattice, which induces a change in the optical properties of the UTFs. Furthermore, an electrochromic device (ECD) based on the (LDH/PB)n-ITO/0.1 M KCl electrolyte/ITO sandwich structure displays superior response properties (0.91/1.21 s for coloration/bleaching), a comparable coloration efficiency (68 cm(2) C(-1)) and satisfactory optical contrast (45% at 700 nm), in comparison with other inorganic material-based ECDs reported previously. Therefore, this work presents a facile and cost-effective strategy to immobilize electrochemically active nanoparticles in a 2D inorganic matrix for potential application in displays, smart windows and optoelectronic devices.
电致变色材料是电致变色器件中最重要和最基本的组成部分。在此，我们通过层层组装技术，基于剥离层状双氢氧化物（LDH）纳米片和普鲁士蓝（PB）纳米粒子制备了高性能电致变色薄膜。X 射线衍射和紫外-可见吸收光谱表明具有周期性层状结构的（LDH/PB）n 超薄薄膜（UTFs）具有均匀和规则的生长。所得的（LDH/PB）n UTF 电极表现出电致变色行为，这是由于 PB 晶格中的可逆 K(+)离子迁移引起的，这导致 UTFs 的光学性质发生变化。此外，基于（LDH/PB）n-ITO/0.1 M KCl 电解质/ITO 夹层结构的电致变色器件（ECD）显示出优异的响应特性（着色/褪色的 0.91/1.21 s）、相当的着色效率（68 cm(2) C(-1))和令人满意的光学对比度（700nm 时为 45%），与以前报道的其他基于无机材料的 ECD 相比。因此，这项工作提出了一种简便且具有成本效益的策略，用于将电化学活性纳米粒子固定在 2D 无机基质中，以应用于显示器、智能窗户和光电设备。
