One of the possible ways to enhance photocatalytic activity is the use of photonic band gap (PBG) materials. Anodic titania photonic crystals (PhCs) are promising PBG structures, whose structure can be tuned easily by anodizing conditions. However, the effect of various doping approaches on the photocatalytic activity of anodic titania PhCs has never been studied before. In our recent work [1] anodic titania PhCs were synthesized by cycling anodizing of titanium with voltage versus charge density modulation followed by annealing at 450 °C in air. The PhCs were post-treated by electrochemical reduction in 0.1 M Na2SO4, annealing in H2/Ar mixture or NH3. Photocatalytic activity of PhCs in the degradation of the methylene blue dye decreases after electrochemical reduction and annealing in NH3, whereas the annealing in H2/Ar at 600 °C for 2 h leads to an increase in the degradation rate constant by 60%.
This work was supported by the Russian Science Foundation (grant number 22-23-20193).
[1] N.A. Sapoletova, S.E. Kushnir, A.N. Ulyanov, R.G. Valeev, O.V. Boytsova, I.V. Roslyakov, K.S. Napolskii, Effect of post-treatment on photocatalytic activity of anodic titania photonic crystals // Optical Materials, 2023, v. 144, 114350. DOI: 10.1016/j.optmat.2023.114350.