Tungsten disulfide (WS2) is a highly active co-catalyst in Fe(III)/H2O2 Fenton-like reactions for efficient acetaminophen degradation

The most important factor that restricts the decomposition of H 2 O 2 in the Fe 3+ /H 2 O 2 reaction is the slow cycling efficiency of reducing Fe 3+ to Fe 2+ . In this study, the addition of tungsten disulfide (WS 2 ) as a co-catalyst achieved a rapid cycling of the reaction rate-limiting step and a significant enhancement of H 2 O 2 decomposition, which resulted in the effective degradation of acetaminophen (APAP). Results show that 99.6% of APAP (5 mg L −1 ) could be degraded by H 2 O 2 /Fe 3+ /WS 2 system within 2.5 min. The conversion of Fe 3+ to Fe 2+ occurred mainly on the surface of WS 2 due to the redox reaction of the exposed W 4+ active sites with Fe 3+ after the unsaturated S atoms were bound to protons. Electron paramagnetic resonance (EPR) and radical quenching experiments evaluated the contribution of hydroxyl radical (•OH) and superoxide radical (O 2 • − ) in the degradation of pollutants. WS 2 showed good recoverability after four cycles of the reaction. This study provides a new perspective to improve the efficiency of Fe 3+ /H 2 O 2 and provides a reference for the involvement of transition metal sulfides in advanced oxidation processes (AOPs).