Piezocatalytic enhanced peroxymonosulfate activation for bisphenol F degradation with amorphous MoSx/h-BN: The pivotal role of sulfur vacancies

Abstract

Amorphous MoSx nanoflowers were synthesized by a one-step hydrothermal method, and hexagonal boron nitride (h-BN) was introduced to form a van der Waals heterojunction to accelerate interfacial electron transfer and enhance the piezoelectric response. The coupling system of piezo and peroxomonosulfate (PMS) with synchronous carrier transfer and separation was constructed. The amorphous MoSx/h-BN catalyst possessed abundant sulfur vacancies, and bisphenol F (BPF) can be completely degraded within 30 min in the piezoelectric-activated peroxomonosulfate (PMS) process. The degradation rate of BPF by the amorphous MoSx/h-BN system was increased by 7.6 times compared with crystalline MoS2/h-BN. The combination of experiments and theoretical calculation results showed that sulfur vacancies acted as reactants and electron capture centers, which promoted carrier separation, provided local catalytic centers indicated by the catalysts, and enhanced the activation efficiency of PMS compared to the non-piezoelectric system. This work provides guidance for the exploitation of green and efficient peroxomonosulfate-based advanced oxidation processes for water remediation.