High piezocatalytic capability in CuS/MoS 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 MoS 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/MoS-0.6 driven by mechanical stirring in the dark. Impressively, the piezoelectric current of CuS/MoS-0.6 is 48 and 35.7 times higher than that of pure CuS and MoS, respectively. The significantly enhanced piezocatalytic performance can be ascribed to the formation of CuS/MoS heterojunction and the piezoelectric field generated by MoS 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.