Title: 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.