Simultaneous Piezoelectrocatalytic Hydrogen‐Evolution and Degradation of Water Pollutants by Quartz Microrods@Few‐Layered MoS₂ Hierarchical Heterostructures

Abstract Intense light attenuation in water/wastewater results in photocatalysts exhibiting a low quantum efficiency. This study develops a novel piezoelectrocatalysis system, which involves quartz microrods (MRs) abundantly decorated with active‐edge‐site MoS₂ nanosheets to form a quartz microrods@few‐layered MoS₂ hierarchical heterostructure (QMSH). Through theoretical calculations, it is found that the quartz MRs serve as a parallel‐plate capacitor, which is self‐powered to provide an internal electric field to the few‐layered MoS₂ nanosheets surrounding the quartz MR surfaces, and the piezoelectric potential (piezopotential) effectively facilitates redox reactions with the free carriers in MoS₂. The self‐powered quartz MRs in the QMSH present an internal bias to the MoS₂ nanosheets, thus yielding a piezoelectrocatalysis system. An efficient piezoelectrocatalytic hydrogen evolution reaction and decomposition of wastewater without light irradiation can be achieved simultaneously. The second‐order rate constant of the QMSH is ≈0.631 L mg⁻¹ min⁻¹, which is 650‐fold that of quartz MRs, indicating that the piezoelectric heterostructural catalysts display exceptionally high efficiency on piezoelectrocatalytic redox reactions rather than in the piezocatalytic process. The H₂‐production rate of QMSH catalysts approaches ≈6456 µmo1 g⁻¹ h⁻¹ and peaks at ≈16.8 mmol g⁻¹ in 8 h. The piezoelectrocatalytic process may be a promising method for treating industrial wastewater and producing clean energy.