P-doped nanorod MoO3 and nanoflower NiAl-LDH construct S-type heterojunction for photocatalytic high-efficiency hydrogen evolution

S-type heterojunction is a new type of photocatalytic heterojunction that can efficiently enhance the performance of photocatalytic hydrogen-producing. In this paper, NiAl-LDH/P-MoO3 composite catalysts were prepared, NiAl-LDH, P-MoO3 and NiAl-LDH/P-MoO3 were characterized, tested and analyzed from the aspects of morphology, structure and spectrum. The 5 h hydrogen-producing amount of NiAl-LDH/P-MoO3 reaches 298.72 μmol, which is 160 times and 16 times that of MoO3 and NiAl-LDH under the visible light, respectively. The doping of P narrows the band gap of MoO3 and is more helpful to the electronic transmission. The irregular P-MoO3 nanorods with a diameter of about 200 nm are attached to 3-4 μml NiAl-LDH nanoflower. The construction of S-type heterojunction changes the electronic transmission pathway of NiAl-LDH/P-MoO3 while improving the electron-hole pair separation ratio of NiAl-LDH/P-MoO3. The strong oxidizing ability of P-MoO3 and the strong reducing ability of NiAl-LDH are retained. Effective control of electronic transmission path improves the photocatalytic hydrogen-producing activity and stability of NiAl-LDH/P-MoO3, which provides a certain theoretical support for the realization of photocatalytic high-efficiency HER by constructing heterojunction.