In-situ synthesis of novel plate-like Co(OH) 2 co-catalyst decorated TiO 2 nanosheets with efficient photocatalytic H 2 evolution activity

Efficient separation of photo-generated electrons and holes is a crucial aspect for photocatalytic hydrogen evolution. Herein, novel plate-like Co(OH) 2 decorated TiO 2 nanosheets for photocatalytic water splitting were synthesized by a facile in-situ synthetic method. The results of X-ray diffractometry (XRD), transmission electron microscope (TEM), UV–Vis diffusion reflectance spectroscopy (DRS) and X-ray photoelectron spectroscopy (XPS) indicate the successfully incorporation of Co(OH) 2 co-catalysts onto the surface of TiO 2 nanosheet photocatalysts. Further photocatalytic hydrogen evolution experiments illustrate that all Co(OH) 2 decorated TiO 2 samples show higher rate of hydrogen production performance than pure TiO 2 sample and the composite sample with Co(OH) 2 loading amount of 0.5mol% presents the highest photocatalytic hydrogen production activity of 746.93 μmol g −1 ·h −1. It is indicated that plate-like Co(OH) 2 particle act as an electron collector, which leads to photo-generated electrons transfer from TiO 2 to Co(OH) 2, and therefore enhance the photocatalytic activity. Based on above results, a possible mechanism is proposed and further verified by surface photovoltage spectra (SPV).