Gd,C,N,S Multi-doped ZrO2 for Photocatalytic Degradation of Indigo Carmine Dye from Synthetic Water under Simulated Solar Light

C, N,S-tridoped ZrO2 and Gd, C, N, S-muti-element-doped ZrO2 were synthesized by homogeneous co-precipitation method with different Gd/Zr ratios. The materials were characterized using Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersed X-ray spectroscopy (SEM-EDX) and UV/Visible spectrometry. UV/Vis diffuse reflectance spectroscopy was employed to estimate band gap energies. Indigo carmine (IC) dye (20 ppm) was chosen as a model for organic pollutants and was used to evaluate the photocatalytic performance of the photocatalysts under simulated solar light. The Gd-doped C,N,S-ZrO2 showed significant visible light induced photocatalytic activity towards the degradation of IC. Highest photocatalytic activity was observed for the 0.6% Gd-doped C,N,S-ZrO2 sample (k=1.46 x 10-2 min-1). The high photocatalytic performance is due to small crystalline size, strong visible light absorption and narrow band gap.