Hard-template synthesis of Ti–V–Mn ternary photocatalysts using gelatin-modified mesoporous silica for efficient methylene blue degradation

Abstract

The rapid expansion of the textile industry, driven by technological progress, has resulted in substantial dye pollution, particularly from methylene blue effluents, which remain highly recalcitrant in aquatic environments. Photocatalysis offers a sustainable and effective pathway for dye degradation, and in this study, Ti–V–Mn ternary photocatalysts were synthesized using a 20% gelatine-modified mesoporous silica hard template. Comprehensive characterization was carried out to establish the relationship between structural and optical properties and photocatalytic performance. XRD revealed that the G–Ti–Mn sample exhibited the highest crystallinity (19.62%), while SEM–EDX confirmed the uniform distribution of all metal precursors. FTIR spectra displayed characteristic M–O vibrations corresponding to Ti–O, V–O, and Mn–O bonding, and UV–Vis DRS showed reduced band gap energies in the range of 1.005–2.39 eV, favoring visible-light activation. BET analysis indicated a typical type IV isotherm, with the G–V–Mn sample exhibiting the highest surface area of 106.67 m²/g and pore diameters of 3.74–4.94 nm, confirming the mesoporous nature of the materials. Photocatalytic evaluation demonstrated that the G–V–Mn system achieved the highest degradation efficiency, removing up to 67.83% of methylene blue under UV–Vis irradiation. These findings highlight the potential of gelatine-assisted mesoporous templates in engineering ternary metal photocatalysts with enhanced structural and optical features for sustainable wastewater treatment applications.