Photothermally boosted Fenton-like activity of copper sulfide toward the catalytic degradation of 4-chlorophenol

Abstract

Fenton/Fenton-like reactions have promising implications in biomedicine and environment-related remediation. However, their applications are still limited because of incomplete light utilization, low energy-conversion efficiency, and inefficient H2O2 utilization. Herein, near infrared (NIR) light absorbance and photothermal conversion were utilized for H2O2 activation to achieve 4-chlorophenol (4-CP) elimination from water by using a typical doped copper sulfide (Cu2−xS) semiconductor developed via a hydrothermal method. The obtained CuS is not only an attractive Fenton-like agent but also exhibits efficient photothermal conversion performance in the NIR spectral range, which broadens the use of the solar spectrum and is beneficial to the photothermal-enhanced Fenton-like degradation process. As expected, by irradiating with an NIR laser (1064 nm), the CuS exhibits excellent NIR absorption capacity and produces hyperpyrexia above 50 ℃. Importantly, the photothermal effects of the CuS nanosheets significantly enhanced the yield of the Fenton-like reaction by accelerating the generation and diffusion of free radicals (h+, •O2-, 1O2, and especially •OH), which enabled the key mechanism for pollutant degradation. In addition, CuS nanosheets exhibited good stability during the degradation of 4-CP, with low metal-ion leakage and a broad pH range applicability, and the degradation rate was hardly affected by laser power, catalyst concentration, and the presence of metal ions. These results demonstrate the strong potential of the photothermal-enhanced Fenton-like effect in pollutant degradation and propose a promising strategy for environmental remediation with the effective utilization of solar energy.