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.

Photodeposition of CoOx nanoparticles on BiFeO3 nanodisk for efficiently piezocatalytic degradation of rhodamine B by utilizing ultrasonic vibration energy

“…The piezocatalytic reaction process can be described as follows: the piezoelectric material deforms under external mechanical stress, causing the misalignment of the centers of positive and negative charges, thereby generating piezoelectric potential. Driven by the piezoelectric field, the thermal-excited free charges in the piezoelectric material are enriched in the opposite direction of the crystal surface, which then triggers the surface electrochemical reaction to achieve dye degradation, CO 2 reduction, water decomposition, etc [14] , [15] , [16] , [17] . The piezoelectric property is the key factor that affects the piezocatalytic behavior of the piezocatalysts.…”

High Efficiency Water Splitting using Ultrasound Coupled to a BaTiO3 Nanofluid

“…The maximum rate of H 2 evolution found was 270 mmol h -1 g -1 and lowest energy consumption of 227 kWh g -1 H 2 (calculated based on the power of the ultrasonic bath) or 10 kWh g -1 H 2 (calculated based on the transferred acoustic power) for a loading of 5mg l -1 of BaTiO 3 in 10% MeOH/H 2 O leading to the highest efficiency of piezoelectrically driven water splitting that has been reported to date. [40,59,60] ). Energy consumption is calculated based on the power of the ultrasonic bath (W) and hydrogen production rate (g h -1 ).…”

MoSe2 Nanoflowers for Highly Efficient Industrial Wastewater Treatment with Zero Discharge

“…In fact, our process can decompose the highest dye concentration ever reported (Table S1 , Supporting Information). [ 34 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 ]…”