O2- enhancement and recombination delay through Ta+gC3N4 addition with ZnO for effective photocatalytic dye decomposition

Photocatalytically efficient ZnO:Ta/g-C3N4 coatings were deposited on stainless steel mesh (SSM) substrates using nebulizer spray technique for effective decomposition of toxic organic dyes discharged as textile effluents. Structure, morphology and composition of the coated material were analyzed using XRD, SEM and EDAX. Dye decomposition studies show that the efficiency increases remarkably when Ta and g-C3N4 are added with ZnO while the addition of Ta also results in moderate enhancement in efficiency. The reasons for this efficiency improvement and the underlying mechanism have been addressed in detail with the support of trapping test, XPS and UV-Vis diffuse reflectance spectroscopic studies.