A novel Z-type multidimensional FeSe2/CuSe heterojunction photocatalyst with high photocatalytic and photoelectrochemical performance

Abstract

A novel Z-type multidimensional FeSe2/CuSe heterojunction photocatalyst was synthesized by a hydrothermal progress. In the reaction, 1D FeSe2 nanorods will load on the surface of 2D CuSe nanosheets to construct heterojunction. This Z-type heterojunction can improve the carriers separated efficiency and reduce internal resistance (as low as 0.31 kΩ). More importantly, the catalysts display both high oxidation and reduction ability confirmed by photocatalytic and photoelectrochemical test. Under the optimum concentration, the catalyst showed 7.4 times of degradation tetracycline hydrochloride rate, and 4 times of photocurrent density than pure CuSe. Active specie O2−• was detected by the electron spin resonance tool during photocatalytic degradation progress which could confirm that a Z-type heterojunction was constructed between CuSe and FeSe2. In this Z-type heterojunction, photoinduced electrons in the conduction band of FeSe2 can directly inject the valence band of CuSe while photoinduced electrons in the conduction band position of CuSe and photoinduced holes in the valence band position of FeSe2 will remain. The remained photoinduced electrons in the conduction band of CuSe can generate O2−• to oxide tetracycline hydrochloride as well as photoinduced electrons to produce hydrogen. This work highlights a simple strategy of Z-tpye selenides heterostructure for oxidation and reduction application.