Waste battery-derived GO/mesoporous TiO2 nanocomposites for visible-light photocatalytic degradation of crystal violet

The current work presents a facile and viable synthesis of anisotropic spindle shape mesoporous TiO 2 (Meso-TiO 2 ) nanoparticles by solvothermal method and their decoration on waste battery derived graphene oxide (GO) nanosheets by a waste to wealth approach to produce GO/Meso-TiO 2 nanocomposite, an efficient sunlight driven photocatalyst for the degradation of crystal violet (CV) dye. The GO/Meso-TiO 2 composites exhibit a pure anatase phase tetragonal crystal structure, reduced agglomeration, several carbon and oxygen containing functional groups, narrowed band gap (2.81 eV), and strong visible-light absorption. Owing to these features, GO/Meso-TiO 2 composites demonstrate enhanced photocatalytic degradation (87.14 %) of crystal violet (CV) dye under 100 min of sunlight irradiation, outperforming conventional TiO 2 photocatalyst. The GO/Meso-TiO 2 composites achieve degradation efficiencies of 87.14 % and 98.58 % at pH 7 and 10, respectively. Scavengers test reveal the dominating role of hydroxyl (∙OH) radicals in the CV dye degradation process. The GO/Meso-TiO 2 catalysts also demonstrate stability, retaining ∼81 % efficiency after four cycles. These findings highlight the novel integration of waste-derived GO with Meso-TiO 2 for efficient, reusable, sunlight-driven wastewater treatment. • Graphene oxide (GO) synthesized from waste dry cell batteries by waste to wealth approach. • Spindle shape mesoporous TiO 2 NPs decorated on GO nanosheets by facile protocol. • GO/Meso-TiO 2 demonstrates reduced band gap and strong visible light absorption. • Enhanced photocatalytic efficiency (87.14 %) under 100 min of sunlight exposure. • Harnessing waste graphite electrodes by preventing environmental pollution, high cost and raw material consumption.