Red Phosphorus Grafted High-Index (116) Faceted Anatase TiO2 for Z-Scheme Photocatalytic Pure Water Splitting

Red phosphorus (RP) is an emerging visible-light-responsive photocatalyst, yet the rapid charge recombination has limited photocatalytic hydrogen production activity. In this work, a Z-scheme heterostructure with RP nanolayer coated on high-index (116) faceted anatase TiO2 nanoparticles (TiO2@RP) is designed and fabricated via chemical vapor deposition. Compared with pristine TiO2 and RP, the optimized TiO2@RP Z-scheme heterostructure exhibits a significantly boosted photocatalytic activity for pure water splitting, with hydrogen evolution rate reaching 12.9 mu molh(-1), under simulated solar light irradiation. The strong interfacial interaction and staggered band alignment between (116) faceted TiO2 and RP result in the formation of built-in electric field, which can drive the directional charge migration from the conduction band (CB) of TiO2 to the valance band (VB) of RP under light irradiation, with photoelectrons and holes of high redox ability maintained at the CB of RP and the VB of TiO2, respectively. This well-designed heterostructure greatly promotes photogenerated charge separation and migration via a direct Z-scheme charge transfer pathway.

Automated summary

In this study, a Z-scheme heterostructure is designed and fabricated by coating a red phosphorus (RP) nanolayer on high-index (116) faceted anatase TiO2 nanoparticles via chemical vapor deposition. The optimized TiO2@RP heterostructure exhibits significantly enhanced photocatalytic activity for pure water splitting, with a hydrogen evolution rate of 12.9 μmol/h under simulated solar light irradiation. This enhanced activity is attributed to the direct Z-scheme charge transfer pathway, which promotes efficient charge separation and migration.