To develop electrochromic thin films for smart windows and low-power displays, homogeneous thin films were produced by spin coating colloidal NiAl layered double hydroxide (LDH) nanocluster solutions on a fluorine-doped tin oxide (FTO) glass substrate. The nano-LDH dispersion was synthesized via a facile one-step epoxide mediated process at room temperature. In situ relative transmittance measurements at 400 nm, recorded during potential scans in cyclic voltammetry or differential pulse chronoamperometry, showed the electrochromic behavior of the homogeneous thin films. The impact of various parameters on the electrochromic properties of the films was detailed, such as the thickness of the film, the nature of the electrolyte, and the presence of electroactive anions. The electrochromic properties, namely, the change in transmittance (ΔT) and the bleaching reversibility, were greatly improved using alkaline metal hydroxide as the electrolyte and in the presence of Fe(CN)₆^4–. The performances that we reached from the deposition of nanoclusters can be advantageously compared to the literature with ΔT = 70% and fast and good reversibility. Upon calcination, the NiAl-LDH film converted into mixed oxides (NiO and NiAl₂O₄). The higher the calcination temperature, the lower was the ΔT value. The presence of porosity within the thin films, through the introduction of sacrificial polymeric beads and then decomposition at 400 °C, was investigated, highlighting an enhancement of the ΔT value attributed to better accessibility to the nickel redox sites.

中文翻译：

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基于NiAl层状双氢氧化物纳米簇的电致变色薄膜，用于智能窗户和低功率显示器

为了开发用于智能窗户和低功率显示器的电致变色薄膜，通过将胶体NiAl层状双氢氧化物（LDH）纳米簇溶液旋涂在掺氟的氧化锡（FTO）玻璃基板上来生产均匀的薄膜。纳米LDH分散体是在室温下通过简便的一步式环氧介导工艺合成的。原位在循环伏安法或差分脉冲计时安培法的电势扫描过程中记录的400 nm的相对透射率测量结果表明，均匀薄膜的电致变色行为。详细介绍了各种参数对薄膜电致变色性能的影响，例如薄膜的厚度，电解质的性质以及电活性阴离子的存在。使用碱金属氢氧化物作为电解质并在存在Fe（CN）₆ ^4–的条件下，可以大大改善电致变色性能，即透射率（ΔT）的变化和漂白可逆性。我们从纳米团簇的沉积中获得的性能可以与具有ΔT的文献进行比较= 70％，快速且良好的可逆性。煅烧后，NiAl-LDH膜转变成混合氧化物（NiO和NiAl ₂ O ₄）。煅烧温度越高，ΔT值越低。通过引入牺牲性聚合物珠粒，然后在400°C下分解，研究了薄膜中是否存在孔隙率，这突出了ΔT值的提高，这归因于更好地接近镍氧化还原位点。