Constructing photocatalyst from β-Bi2O3 photonic crystals for enhanced photocatalytic performance

Abstract

Photonic crystals with highly ordered structure have presented a prospective application in the design of photocatalysts. Herein, we fabricated visible-light active β-Bi2O3 photonic crystals via a modified sandwich infiltration method. By using the acetylacetone-complexed metal ion precursors, pure β-Bi2O3 photonic crystals with highly ordered structure could be obtained at a calcination temperature of 400 °C. Benefited from the facilitated mass transport in the highly ordered structure, β-Bi2O3 photonic crystals exhibited higher photocatalytic activity towards organic pollutions degradation than porous β-Bi2O3 and β-Bi2O3 nanocrystals. Furthermore, the photonic band gap of β-Bi2O3 photonic crystals could be modulated to overlap its electronic band gap by changing the macropore diameter into 220 nm. Slow photon effect could be observed over the β-Bi2O3 photonic crystals with a pore diameter of 220 nm, which enhanced the electronic band gap absorption and further improved the corresponding photocatalytic activity. The enhanced activity stability of β-Bi2O3 photonic crystals could also be observed. Based on the detection of active species, the degradation mechanism over β-Bi2O3 photonic crystals was discussed. The fabrication of β-Bi2O3 photonic crystals in this study provides experimental guidance for developing photonic crystals with enhanced visible light absorption and photocatalytic activities.