Au@Pt decorated polyaniline/TiO 2 with synergy of p-n heterojunction and surface plasmon resonance for boosted photoelectrochemical water splitting

One of the most promising approaches to addressing the current global energy and environmental crisis is the development and utilization of hydrogen energy. Photoelectrochemical (PEC) water splitting represents a clean and sustainable method for converting solar energy into hydrogen. In this article, we employed a hydrothermal-photodeposition method to fabricate Au@Pt decorated polyaniline (PANI)/TiO 2 (TNAP), which realized the synergy of p-n heterojunction and surface plasmon resonance (SPR). Experimental results revealed that p-n heterojunction can be formed between PANI and TiO 2, whereas PANI can utilize visible light and the strong interaction between Au and PANI can realize the rapid transfer of hot electrons. Meanwhile, the outer layer Pt nanoparticles can accelerate water oxidation reaction kinetics. Therefore, the as-prepared TNAP exhibited the synergy promotion of p-n heterojunction and SPR effect, which is benefit for promoted light utilization and efficient charge transfer and separation. The optimized TNAP structure achieved hydrogen evolution rate of 19.26 μmol/cm 2 ·h and photocurrent density of 1.20 mA/cm 2 at a bias of 1.23 V vs. RHE, which is significantly higher than that of single semiconductor. This article suggests that the synergy promotion of SPR effect and p-n heterojunction is an efficient strategy to promote the efficiency of PEC water splitting.