Preparation of TiO2/Ni‐NG Mesoporous Microspheres and Photocatalytic Hydrogen Evolution Properties.

The regulation of surface active sites and structures is a key factor affecting the performance of photocatalysts. In order to prepare monodisperse anatase TiO2 mesoporous microspheres with higher specific surface area, smaller pore size and particle size, a dual‐surfactant orientation assembly method was selected. Graphene (NG) was selected as a cocatalyst to compound with mesoporous TiO2 and nickel doping was performed on the cocatalyst to improve the photocatalytic hydrogen production activity of the semiconductor photocatalyst. Through proper regulation and rational design, the semiconductor photocatalyst with desired properties was prepared. SEM characterization of mesoporous titanium dioxide (TiO2/Ni‐NG) with graphene cocatalyst proved that TiO2 nanospheres have good monodispersion, and TiO2 nanospheres are well supported on graphene cocatalyst. The composite material belonged to mesoporous group with the pore size being mainly distributed between 10–20 nm. The loading of graphene and Ni‐NG cocatalyst increased the absorption band edge by 9 nm and 38 nm, respectively, and the band gap decreased by 0.07 eV and 0.16 eV, respectively. The selection of graphene as cocatalyst improved the hydrogen production activity of photocatalyst and nickel doping was very effective in the modification of graphene. For reaction time of 2.5 h, the H2 production of TiO2/Ni‐NG material reached 1.767 mmol/g which was 7.27 times that of TiO2/NG composite material. [ABSTRACT FROM AUTHOR]