Charge-Induced Interfacial Assembly Synergizing Photocatalytic Air Purification With Structural Color Decoration

The release of toxic gases from traditional visual decorative materials poses a significant health hazard to urban life. Here, inspired by the sheath wings of beetles, a structurally colored photocatalytic coating combining aesthetic value and air-purification functionality is proposed for novel decoration applications. The coating was formed by charge-induced interfacial crystallization and calcination of metal-organic frameworks (MOF) in an opal photonic crystal template. The inverse opal structure endows the coating with non-iridescent structural colors and high light-trapping efficiency. Meanwhile, the prepared carbon-doped porous ZnO with rich oxygen vacancies endowed the coating with additional active sites and a narrowed bandgap, leading to excellent photocatalytic ability, which is confirmed by theoretical simulations. The enhanced photocatalysis of the prepared coatings is effective in degrading HCHO (the most common indoor pollutant) by 99.9%, while killing bacteria by 99.65% with excellent recyclability. These properties, arising from the synergistic effect of carbon-doping/oxygen vacancies and the inverse opal structure, make the bio-inspired structural colored photocatalytic coating have great potential as decorative wall materials with the functionality of governing the air environment.