Preparation and photocatalytic degradation of PTCN/SnS2/Ti3C2 QDs composites

Abstract

In this study, Ti₃C₂ quantum dots (QDs) were prepared via a simple hydrothermal method and loaded onto binary catalytic materials to construct ternary PTCN/SnS₂/Ti₃C₂ QDs composites for enhancing photocatalytic performance. The materials were characterized using techniques such as XRD, TEM, FT-IR, UV–vis, BET, XPS, and PL. The results showed that Ti₃C₂ QDs were uniformly dispersed on the surface of PTCN/SnS₂, forming a stable heterostructure. The specific surface area increased to 68.847 m²/g (5.6 times higher than that of PTCN), the visible light absorption edge redshifted to 532 nm, and the band gap narrowed to 2.1 eV. Under visible light, the composite exhibited degradation rates of 90.53 %, 79.53 %, 81.23 %, and 85.62 % for norfloxacin, pefloxacin, enrofloxacin, and ciprofloxacin, respectively. At the optimal doping amount (k = 0.0408 min⁻¹), the catalytic activity was 6.21 times that of pure PTCN and 2.87 times that of PTCN/SnS₂. Cyclic experiments demonstrated excellent stability of the composite, with a degradation rate remaining at 86 % after 5 cycles. This study is the first to construct the PTCN/SnS₂/Ti₃C₂ QDs ternary system and propose a Z-scheme charge transfer mechanism, providing new insights for the design of high-efficiency photocatalytic materials.