The high photocatalytic efficiency and stability of LaNiO 3 /g-C 3 N 4 heterojunction nanocomposites for photocatalytic water splitting to hydrogen

A binary direct Z-scheme LaNiO3/g-C3N4 nanocomposite photocatalyst consisted with LaNiO3 nanoparticles and g-C3N4 nanosheets was successfully synthesized by means of mechanical mixing and solvothermal methods in order to improve the photocatalytic water splitting activity. The as-prepared materials were characterized by powder X-ray diffraction (XRD), Scanning Electron microscope (SEM), Transmission Electron microscope (TEM), X-ray photoelectron spectroscope (XPS), Fourier Transform Infrared Spectroscopy (FT-IR) and N2 adsorption–desorption experiments, respectively, demonstrating the formation of interfacial interaction and heterogeneous structure in LaNiO3/g-C3N4 nanocomposites. Under UV-light irradiation, the LaNiO3/g-C3N4 samples which without the addition of any noble metal as co-catalyst behaved enhanced photocatalytic water splitting activity compared with pure LaNiO3 and g-C3N4, owing to the Z-scheme charge carrier transfer pathway. Especially, the LaNiO3/70%g-C3N4 nanocomposite reach an optimal yield of up to 3392.50 µmol g−1 in 5 h and held a maximum H2 evolution rate of 678.5 µmol h−1 g−1 that was 5 times higher than that of pure LaNiO3.