Fabrication of NiFe-LDH/MoS2 2D/2D material to construct direct Z-scheme heterojunction for enhanced CO2 photocatalytic reduction under visible light irradiation

Abstract

In recent years, the utilization of solar energy for conversion of CO2 into fuels has emerged as a promising strategy for mitigating the Greenhouse effect. However, transport efficiency of photogenerated carriers plays a crucial role in determining the efficacy of CO2 photocatalytic reaction. In this paper, a 2D/2D composite material consisting of NiFe-LDH/MoS2, presenting high efficiency in separating photogenerated electron-hole pairs, has been successfully synthesized using a straightforward hydrothermal method. XRD, XPS, FTIR and other characterization results proved that the composite was successfully prepared, and its unique direct Z-scheme heterostructure improved the efficiency of CO2 photocatalytic reduction effectively. The composite material NiFe-LDH/MoS2 demonstrated enhanced rate of photo-induced electron-hole pair separation comparing with pure NiFe-LDH. Apart from this, the charge transfer resistance was reduced simultaneously, the composite material exhibited perfect photocatalytic activity. In photocatalytic reduction reaction experiment, CO yield of NiFe-LDH/MoS2 can reach 10.72 μmol/g, which is 3.93-fold and 4.17-fold that of bare NiFe-LDH and MoS2. The cyclic test also shows that the catalyst has good stability under visible light irradiation.

Keywords

• CO2 photocatalytic reduction
• Layered double hydroxide
• Z-scheme heterojunction
• MoS2