Design of (GO/TiO 2 ) N one-dimensional photonic crystal photocatalysts with improved photocatalytic activity for tetracycline degradation

(GO/TiO2)N (GO represents graphene oxide, and N represents the period number of alternate superposition of two dielectrics) one-dimensional photonic crystal with different lattice constants was prepared via the sol-gel technique, and its transmission characteristics for photocatalysis were tested. The results show that the lattice constant, filling ratio, number of periodic layers, and incident angle had effects on the band gap. When the lattice constant, filling ratio, number of periodic layers, and incident angle were set to 125 nm, 0.45, 21, and 0°, respectively, a gap width of 53 nm appeared at the central wavelength (322 nm). The absorption peak of the photocatalyst at 357 nm overlapped the blue edge of the photonic band gap. A slow photon effect region above 96% reflectivity appeared. The degradation rate of tetracycline in (GO/TiO2)N photonic crystal was enhanced to 64% within 60 min. Meanwhile, the degradation efficiency of (GO/TiO2)N one-dimensional photonic crystal was effectively improved compared with those of the GO/TiO2 composite film and GO/TiO2 powder.