Sucrose-based reticulated vitreous carbon modified with N-doped TiO2 as an adsorbent and photocatalyst: Enhanced removal of methyl orange from aqueous solutions

A novel and low-cost 3D reticulated vitreous carbon (RVC) was synthesized and modified with (N-TiO2) to obtain an RVC/N-TiO2 composite, which was employed to remove methyl orange in an aqueous solution. This material was synthesized using the sacrificial template method and impregnated with an environmentally friendly sucrose resin, followed by N-TiO2 impregnation by dip-coating technique. SEM-EDS characterization confirmed the uniform covering of the TiO2, and XRD, Raman, and XPS evinced the presence of anatase and rutile polymorphs in the film and the N-doping, respectively. N-TiO2 coating onto RVC provides a higher specific surface area and electrochemical active area, boosting the wettability and the adsorption capacity. Additionally, this film favoured the photoelectrochemical response of the composite and the generation of center dot OH radicals. The adsorption, desorption, and photocatalytic studies demonstrated that >95 % decolorization of MO was achieved in 30 min without light irradiation and that >95.5 % degradation was attained in 120 min under visible light. The foam demonstrated reusability for over five cycles of adsorption/desorption of MO, with a capacity to recover up to 99 % of the dye after the first cycle and up to 94.07 % after the fifth cycle. Meanwhile, the minimal desorption of the dye (2.5 %) after illumination confirmed the photocatalytic degradation. This indicates that the process was not merely adsorption but also photocatalytic degradation.