Boron carbonitride sheet/ Cu2O composite for an efficient photocatalytic hydrogen evolution

Highlights: • BCN/Cu₂O composite was prepared by simple thermal condensation technique. • Cu₂O loading on BCN sheets shows reduced bandgap of 2.34eV. • Visible light photocatalytic hydrogen production of the composite over bare BCN was found to be enhanced by 59.5%. • Steady rate of hydrogen production was achieved over repeated cycles of usage. Cu₂O nanoparticles were directly formed on the boron carbonitride (BCN) sheets by thermal condensation technique. Photocatalytic hydrogen evolution efficiency was greatly influenced by three-dimensional distribution and loading of Cu₂O in the nanocomposite network structure. The oxidation state, crystalline phase, and size of the supported/un-supported nanoparticles were observed by XPS and XRD, and the internal morphology was determined via HR-TEM analysis. Visible light response and band position was confirmed by measuring the diffuse reflection spectroscopy (DRS). An efficient thermal, combined with a condensation method, was used to synthesize these nanocomposite architectures, which were then embedded into the BCN network. The broad visible light absorption of the synthesised nanocomposites was influenced by Cu₂O loading on BCN sheets. The red shift in UV spectra of BCN/Cu₂O confirmed that presence of Cu₂O on BCN sheets resulted in reduced bandgap compared with the wider bandgap in BCN sheets. The H₂ evolution activity was 59 μmol/h for the prepared composites, which is 59.5% enhanced compared with bare BCN. The enhanced photocatalytic activity was due to the influence of Cu₂O on the BCN surface and enhanced charge separation in the interface at Cu₂O with BCN.