NIR Photothermal-Enhanced Electrocatalytic and Photoelectrocatalytic Hydrogen Evolution by Polyaniline/SnS2 Nanocomposites

A series of polyaniline (PANI)-decorated SnS2 nanoplates (PANI/SnS2) were produced via a hydrothermal method followed by a liquid–solid mixing. The PANI/SnS2 nanocomposites were composed of amorphous PANI and hexagonal-phase SnS2 nanoplates. Infrared thermal images revealed that PANI had an excellent near-infrared (NIR)-induced photothermal effect. Overall, the PANI/SnS2 nanocomposites showed better NIR-enhanced electrocatalytic and photoelectrocatalytic hydrogen evolution activity than bare SnS2 nanoplates. The optimized 4% PANI/SnS2 (which contained 4 wt % PANI) displayed the largest electrochemical double-layer capacitance (Cdl) value (0.85 mF cm–2) and the lowest Tafel slope of 66 mV dec–1 in 0.5 M H2SO4 under NIR irradiation. It was investigated and confirmed that the photothermal effect and the synergistic effects between SnS2 and PANI heterostructure played important roles in promoting electrocatalytic and photoelectrocatalytic hydrogen evolution processes.