Biochar modified Co–Al LDH for enhancing photocatalytic reduction CO2 performance and mechanism insight

This study prepared a biochar-based photocatalyst (Co–Al LDH–C) via facile ultrasonic-assisted solvent treatment. The Co–Al LDH–C photocatalyst shows better photocatalytic activity in CO2 reduciton than the pure Co–Al LDH without biochar modification. The Co–Al LDH–C affords a CO generation rate of 29.2 µmol g−1. The enhanced CO2 reduction activity is attributed to the biochar in Co–Al LDH enhanced the light absorption property and separation efficiency of the charge carriers. Additionally, a mechanism insight of Co–Al LDH reduction CO2 is also investigated by a series of characterizations and experiments results. This work offers a new insight for CO2 reduction by waste utilization of biomass and improved the performance of Co–Al LDH, and extends the broad potential application of biochar-based photocatalyst in the photocatalytic conversion from solar to carbon resource.