High piezocatalytic capability in CuS/MoS₂ nanocomposites using mechanical energy for degrading pollutants

Piezocatalysis, driven by mechanical energy and piezoelectric effect, is of great potential in addressing the environmental issues. In this work, a piezoelectric catalyst was fabricated by growing few-layer MoS₂ nanosheets onto CuS, for the piezocatalytic degradation of Rhodamine B (RhB), methylene blue (MB) and hexavalent chromium (Cr (VI)). The excellent removal efficiency of Cr (VI) and RhB can be reached 100% within 180 s, through the piezocatalysis of CuS/MoS₂-0.6 driven by mechanical stirring in the dark. Impressively, the piezoelectric current of CuS/MoS₂-0.6 is 48 and 35.7 times higher than that of pure CuS and MoS₂, respectively. The significantly enhanced piezocatalytic performance can be ascribed to the formation of CuS/MoS₂ heterojunction and the piezoelectric field generated by MoS₂ nanosheets, which promotes the efficient separation of electrons and holes. This study provides insights into strategies to improve catalytic performance through utilizing mechanical energy and opens a new horizon for environmental remediation.