Mesoporous TiO2-GO-Cu Aerogel synthesized via classical sol-gel/supercritical drying route: High specific surface area and enhanced visible light photodegradation

Developing highly efficient photocatalysts is crucial for solar-driven wastewater treatment, particularly in enhancing catalytic efficiency and visible-light response. In recent years, most researchers have utilized hydrothermal methods to integrate TiO₂ with graphene aerogels, thereby improving charge separation efficiency. However, severe buildup of graphene sheets will result in insufficient absorption of visible light. To address the limitation, this work directly used titanium dioxide aerogel as the framework, introduced graphene and nano-Cu particles, and combined the sol-gel method to construct a TiO 2 -GO-Cu ternary aerogel structure(TGCA), achieving the multi-component synergistic effect of the active components. The phase composition and mesoporous structure of the material were characterized by scanning electron microscopy, ultraviolet-visible spectrophotometry, N 2 adsorption test, etc. A large specific surface area of 692.9 m 2 /g and excellent pore structure were achieved. Moreover, under visible light irradiation, the degradation efficiency of Rhodamine B (RhB) reached 100% within 30 minutes, and the band gap was reduced to 2.75 eV. After eight cycles, the photocatalyst retained 76.18% of its degradation efficiency, outperforming most TiO₂-graphene materials. This study significantly improved the photocatalytic performance of the catalyst through structural regulation, optimization of electron transport, and enhancement of light absorption. It thereby offers a feasible approach and valuable reference for solar-driven wastewater treatment technologies.