Abstract Herein, we demonstrate electrochromism of charged inverse opal photonic gel (IOPG) in aqueous solution for full color reflective display. Opal-templated polymerization of hydroxyethyl methacrylate with ionizable monomer and subsequent etching formed the IOPG exhibiting a structural color by Bragg diffraction of light. The IOPG contained acrylic acid (AA) (or vinyl imidazole (VI)) that can be ionized above the pKa (or below the pKb) of the gel. Application of 4 V bias induced apparent color changes of the AA-IOPG from red to green due to decreased osmotic pressure within the IOPG near the ITO surface. It was revealed that the local pH change by water-splitting under voltage bias is the main driving force for IOPG deswelling. The blue shift of the colors during voltage ON was found to be faster than the red shift at voltage OFF due to the electrophoretic migration of protons. The VI-IOPG, which swells at low pH due to a positively charged hydrogel, showed a slight red shift of the reflective color by voltage ON and blue shift upon when voltage OFF. The reproducible color changes of AA-IOPG upon the repeated ON/OFF bias clearly showed that the IOPG can be a promising candidate for a reflective display.

中文翻译：

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电致变色反蛋白石光子凝胶在水性介质中含有带电水凝胶，用于全色反射显示

摘要在此，我们展示了带电反蛋白石光子凝胶 (IOPG) 在水溶液中的电致变色，用于全色反射显示。甲基丙烯酸羟乙酯与可电离单体的蛋白石模板聚合和随后的蚀刻形成了 IOPG，通过光的布拉格衍射显示出结构颜色。IOPG 含有丙烯酸 (AA)（或乙烯基咪唑 (VI)），可在凝胶的 pKa 以上（或 pKb 以下）离子化。由于靠近 ITO 表面的 IOPG 内渗透压降低，4 V 偏置的应用导致 AA-IOPG 从红色到绿色的明显颜色变化。结果表明，偏压下水分解引起的局部pH变化是IOPG消溶胀的主要驱动力。由于质子的电泳迁移，发现电压开启期间颜色的蓝移比电压关闭时的红移更快。由于带正电荷的水凝胶，VI-IOPG 在低 pH 值下膨胀，显示出反射颜色因电压打开而发生轻微红移，在电压关闭时显示蓝移。AA-IOPG 在重复 ON/OFF 偏压下可再现的颜色变化清楚地表明 IOPG 可以成为反射显示器的有希望的候选者。