Green batch prepared a novel C/P co-doping urchin-like TiO2 for enhanced photocatalytic degradation and mineralization of trimethoprim

Abstract

In advancing the practical application of photocatalytic degradation for pollutant removal, batch preparation of environmentally friendly photocatalysts plays a crucial role. Herein, we prepared C/P co-doped urchin-like TiO₂ (C/P–TiO₂) through a straightforward room temperature impregnation and atmospheric annealing process. Phytic acid served as the dopant precursor for introducing C and P onto the TiO₂ surface. This doping process was verified through energy dispersive X-ray spectroscopy (EDX), electron spin resonance (ESR), and X-ray photoelectron spectroscopy (XPS) analysis. The C/P–TiO₂ photocatalyst exhibited exceptional efficiency in degrading the target compound trimethoprim (TMP), achieving a degradation of 98% TMP within 60 min and a mineralization of 40% TMP within 120 min, which were respectively 2.4 and 1.6 times higher than that of pristine TiO₂. The intermediate products of TMP were detected, and a plausible degradation pathway was proposed. Photoelectric characterization results also confirmed that C/P co-doping could effectively enhance the carrier separation efficiency of C/P–TiO₂. The catalysts prepared using the scaled-up impregnation system and reusing the phytic acid solution consistently demonstrated stable catalytic performance, which confirmed the viability of the method for green and batch preparation of C/P co-doped TiO₂. Notably, the obtained catalyst consistently exhibited high degradation efficacy in various real water bodies, highlighting its substantial potential for practical application. The green and batch preparation method of C/P–TiO₂ introduces a novel approach to the practical application of photocatalysis technology in treatment of water contaminants.