Fabrication of β-In2S3/NiAl-LDH heterojunction photocatalyst with enhanced separation of charge carriers for efficient CO2 photocatalytic reduction

[Display omitted] •30% In2S3/NiAl-LDH exhibited the best photocatalytic performance.•Efficient separation of photogenerated electron-hole pairs.•A perfect band matching and efficient internal charge transfer within the n-n junction. A novel ball-flower In2S3/NiAl-LDH heterojunction photocatalyst was synthesized via a simple one-step hydrothermal approach for the first time and applied for CO2 photocatalytic reduction. The In2S3/LDH composites exhibited excellent photocatalytic performance and stability in CO2 photoreduction in water under the irradiation of simulated solar light. Experimental results indicated that the 30% In2S3/NiAl-LDH heterojunction photocatalyst exhibited the best photocatalytic performance. And the maximum CH4 yields of 36.1 μmol/(h·g-cat) under 7 h visible light irradiation was about 2.5 and 3.5 times of unadulterated LDH and In2S3. The enhanced photocatalytic performance of 30% In2S3/NiAl-LDH catalyst was due to the highly-efficient separation of photogenerated electron-hole pairs, its larger specific surface area and stronger visible-light absorption capacity.