Nickel-based tungstate supported with different forms of SnS2 to achieve improved photocatalytic performance

Semiconductor materials have been applied in many research directions such as photoelectrocatalysis, and shortening the electron transport pathway by coupling semiconductors is an effective path to promote the capability of photocatalytic hydrogen-producing. The crystalline SnS ₂ and amorphous SnS ₂ were combined with NiWO ₄ respectively, in the respective optimal hydrogen-producing conditions, it was 298.6 μmol for SnS ₂/NiWO ₄ (amorphous J-SnS ₂ and NiWO ₄) and 228.5 μmol for J-SnS ₂ NiWO ₄ (crystalline SnS ₂ and NiWO ₄). A series of characterization results showed that SnS ₂/NiWO ₄ showed better photocatalytic hydrogen-producing performance than J-SnS ₂/NiWO ₄ under the same test conditions. The catalysts SnS ₂ and NiWO ₄ were constructed into p-n type heterojunction SnS ₂/NiWO ₄ by electrostatic self-recombination. SEM, XRD and electrochemical tests demonstrate that the high hydrogen-producing performance of SnS ₂/NiWO ₄ is due to the establishment of p-n heterojunction, which enhances the electron transport efficiency. The experimental data were used to test the photocatalytic hydrogen-producing activity of SnS ₂/NiWO ₄ with the control variable method, then it was proved that the photocatalytic hydrogen-producing volume of SnS ₂/NiWO ₄ reached 298.6 μmol in 5 h, which was 3.51 times that of NiWO ₄ at 5 h hydrogen-producing of 85 μmol. The morphology of nanoparticles NiWO ₄ attached to a smooth surface sphere SnS ₂ provides a larger specific surface area and more reactive sites for the photocatalytic eosin hydrogen-producing system, in addition the establishment of p-n type heterojunction structure effectively improves the utilization rate of the sacrificial TEOA and photosensitizer EY, thereby improving the hydrogen-producing performance of SnS ₂/NiWO ₄, which offers a feasible policy for photocatalytic efficient hydrogen-producing technology.