Cu2−xSe/FeSe2 Z-type heterojunction demonstrate versatile boosting photoelectrochemical, electrocatalytic and photocatalytic properties

A multi valence state Cu2−xSe/FeSe2 (CFS) Z-type heterojunction catalyst was constructed by hydrothermal synthesis of 0D Cu2−xSe nanoparticles supported on 1D FeSe2 nanorods. In the catalysts, the Cu2−xSe shows multi valence as Cu2+ and Cu+ as well as FeSe2 had two valence states: Fe2+ and Fe3+. This multivalent state is conducive to electron transport, will reduce its resistivity, and change among different valence states in electrochemical reactions, resulting in improve its photoelectrochemical and electrocatalytic performance. Moreover, this Z-type heterojunction catalyst exhibited good oxidation and reduction ability which reveals the appropriate 0D/1D structure improves the carrier transport. That has been confirmed by photoelectrochemical, electrocatalytic and photocatalytic tests. Under the optimal composited ratio, the degradation rate (k) and photocurrent density of the heterojunction photocatalyst were 1.35 and 3.65 times higher than those of Cu2−xSe, respectively. The detected superoxide radical (O2-•) could prove the formation of Z-type heterojunction. This work provides a new strategy for developing a multifunctional boosted catalyst and reveals their promising applications in photoelectrochemistry, electrocatalysis, and photocatalysis.