NiS modified SrTiO3:Al bifunctional photocatalyst for H2 generation and cathodic protection

Developing low-cost and high-efficiency non-precious metal cocatalysts is the key to the practical application of photocatalysis technology. Here, nickel sulfide (NiS) nanoparticles were synthesized on the surface of strontium titanate (SrTiO3) via a hydrothermal method, identifying the optimal loading molar concentration of NiS as 10%. The solar-to-hydrogen efficiency (STH) of 10%NiS/SrTiO3:Al was enhanced by 97 times compared to SrTiO3:Al and by 1.62 times compared to RhCrCoOx/SrTiO3:Al. This improvement is primarily attributed to the metallic-like properties of NiS, which enhance the photocatalyst's light absorption capacity and charge transfer capability. Additionally, the STH value of samples loaded with both NiS and RhCrCoOx reached 0.436%, indicating a positive synergistic effect in photocatalysis between NiS and RhCrCoOx. Their photocathodic protection capability was also studied in simulated seawater conditions, showing a reduced self-corrosion potential (-0.31V) and a low interface charge impedance (5962 KΩ). This work reveals the potential of NiS as an alternative to precious metal cocatalysts, offering new possibilities for developing cost-effective and high-performance materials for photocatalytic water splitting and photocathodic protection.