Research paperEnhanced photocatalytic activity induced by sp3 to sp2 transition of carbon dopants in BiOCl crystals

•Carbon atoms are doped into BiOCl crystals via glucose treatment.•The carbon dopants exhibit a transition from sp3 to sp2 hybridization at elevated temperature.•The increased content of sp2 hybridization facilitates charge separation and hole transport.•One order of enhancement in photocatalytic activity is achieved toward phenol degradation under visible light.

The insufficient light absorption and low quantum efficiency limit the photocatalytic performance of wide bandgap semiconductors. Here, we report a facile strategy to engineer the surface disordered defects of BiOCl nanosheets via carbon doping. The surface defects boost the light absorption and also the quantum yields, as the doped carbon atoms exhibit a transition from sp3 to sp2 hybridization at elevated temperature, corresponding to a change of assembly state from 3D cluster to 2D graphite-like structure. This transition results in an effective charge separation and thus one order of enhancement in photocatalytic activity toward phenol degradation under visible light. The current study opens an avenue to introduce sp3 to sp2 transition of carbon dopants for simultaneous increment of light absorption and quantum efficiency for application in photocatalysis and energy conversion.

Graphical abstractThe transition of carbon dopants from sp3 to sp2 hybridization and the enhancement in photocatalytic activity under visible light.Download high-res image (234KB)Download full-size image