Abstract We report the direct synthesis of various WO3 nanostructures (nanoplates, nanobricks, and stacked nanosheets) on fluorine-doped tin oxide conducting substrates for electrochromic and pseudocapacitive energy storage applications. These nanostructures were formed by varying the pH of the hydrothermal solution, which led to monoclinic and triclinic crystal structures. Among these structures, vertically aligned WO3 nanoplates showed good electrochromic properties, with rapid and reversible response of the colored and bleached states in 0.5 M H2SO4 electrolyte. Moreover, the vertically aligned WO3 nanoplates exhibited promising energy storage behavior as a negative electrode material with a higher areal capacitance of 72.6 mF cm−2 in 0.5 M Na2SO4 electrolyte and better electrochemical performance than the nanobricks and stacked nanosheets. The two-dimensional WO3 nanoplates exhibit strong potential for use in smart windows and negative-electrode pseudocapacitors.

中文翻译：

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水热生长的 WO3 纳米结构的电致变色和赝电容行为

摘要 我们报告了在掺氟氧化锡导电基底上直接合成各种 WO3 纳米结构（纳米板、纳米砖和堆叠纳米片），用于电致变色和赝电容储能应用。这些纳米结构是通过改变水热溶液的 pH 值形成的，这导致了单斜和三斜晶体结构。在这些结构中，垂直排列的 WO3 纳米片显示出良好的电致变色性能，在 0.5 M H2SO4 电解质中具有快速且可逆的着色和漂白状态响应。此外，垂直排列的 WO3 纳米片作为负极材料表现出良好的储能行为，在 0.5 M Na2SO4 电解质中具有 72.6 mF cm-2 的更高面积电容和比纳米砖和堆叠纳米片更好的电化学性能。