Enhanced Photocatalytic Activity of nano WO3 via Thermal Plasma Treatment and Porphyrin Hybridization

Abstract

Surface modification of semiconductor photocatalysts is a frontier strategy for amplifying activity and facilitating advanced environmental applications. In this study, we demonstrate that tungsten trioxide (WO3) nanoparticles subjected to surface engineering by DC thermal plasma, followed by hybridization with the Tetrakis (4-carboxyphenyl) porphyrin (TCPP) can yield a robust inorganic-organic hybrid with significantly enhanced photocatalytic activity in water treatment. The plasma process optimally tunes particle morphology and introduces abundant surface defects modulating bandgap energies and promoting superior charge separation, and substantially increasing the reactive surface area. Subsequent TCPP hybridization acts synergistically, leveraging the strong π-conjugation and light absorption of porphyrins to extend the photocatalyst's spectral response and foster interfacial charge transfer. Photocatalytic performance studies show that the hybrid material markedly outperforms either parent component alone, attaining rapid RhB degradation kinetics under visible light. This result is attributed to a combination of tailored surface area, engineered defect states, and organic-inorganic interfacial charge dynamics.