Experimental Details: Preparation of anodic aluminum oxide (AAO) membrane: The AAO membranes with average pore diameters of 50, 90, and 200 nm were prepared by ourselves. The aluminium foil (purity 99.5%) was anodized in 0.5 mol/L of oxalic acid solution or 0.36 mol/L of phosphoric acid solution. The AAO membranes with an average pore diameter of 300 nm was purchased from Whatman Ltd. Preparation of SiO 2 colloidal crystal: Nearly monodisperse SiO 2 microspheres with an average diameter of 220

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... m were synthesized by hydrolyzing tetraethyl orthosilicate (TEOS) and subsequent seed growth polymerization under basic conditions. [1] SiO 2 colloidal crystal was obtained by self-assembling SiO 2 microspheres using a vertical deposition technique. The SiO 2 colloidal crystal was heat-treated at 800 ºC for 3 h. The heat treatment Supplementary Material (ESI)