Visible-light driven photocatalytic degradation of triphenylmethane and azo dyes using a graphene oxide reinforced pectin hydrogel.

A three-dimensional network structure comprising pectin, glutaraldehyde and graphene oxide (PGG) was effectively combined to create a composite hydrogel that enhances photocatalytic degradation by producing reactive oxygen species in response to visible light. The PGG hydrogel was created to address issues with photocatalyst performance, including low adsorption capacity and low degradation efficiency. The material was comprehensively characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) isotherm analysis. The PGG hydrogel demonstrated superior structural and functional features by outperforming comparative investigations of swelling ratio and gelation time. With initial dye concentrations of 100 mg/L for Malachite green and 80 mg/L for Metanil yellow, the ideal pH values for degradation were found to be 8 and 6, respectively. Over several cycles, the PGG hydrogel maintained a high degrading efficiency for MG at 99 % and for MY at 99.5 % while demonstrating exceptional stability and reusability.