Vertically aligned Pt/TiO₂ nanobelt films on Ti sheets for efficient degradation of a refractory ethyl...

Noble metal modified TiO₂ nanostructures on a substrate featuring a two-dimensional (2D) morphology are of great interest in wastewater remediation due to high photocatalytic activity and avoidance of separating powder catalysts from water. In this work, vertically aligned Pt/TiO₂ nanobelt films (Pt/TNFs) on Ti sheets were fabricated via a synthesis strategy including an alkaline hydrothermal treatment and electrostatic self-assembly. The Pt/TNFs had a BET specific surface area of 93.35 m² g^-1, showing high adsorption capacity in removing an ethyl thionocarbamate (ETC) flotation collector. After the deposition with Pt nanoparticles, the photocatalytic activity of the TNFs increased by 94.98% with the enhanced mineralization of the ETC collector. Moreover, the Pt/TNFs on Ti sheets exhibited strong substrate adhesion enabling superior photocatalytic stability in the cyclic degradation of ETC. The solid phase extraction and gas chromatography-mass spectrometry (SPE/GC-MS) analysis revealed that seven byproducts still remained even when 100% of ETC was degraded, showing the difficulty in the complete mineralization of the ETC collector. The Pt/TNF can serve as a promising photocatalyst to treat mineral flotation wastewaters containing organic reagents.