Three-phase interface of SnO2 nanoparticles loaded on hydrophobic MoS2 enhance photoelectrochemical N2 reduction

Photoelectrochemical nitrogen reduction (PEC NRR) provides a clean and sustainable method for the production of NH3 under environmental conditions. However, low reaction efficiency remains a major challenge due to the presence of competitive hydrogen evolution reactions (HER). Herein, nanocomposites (SNP/MSO) with three-phase interface were prepared by loading hydrophilic SnO2 nanoparticles (SNP) on hydrophobic MoS2 (MSO) obtained by surface modification with silicomolybdic acid. The hydrophobic interface eliminated the transport barrier of N2 in the liquid phase to the reaction center, inhibiting HER since the lowered contact area with the liquid proton. Meanwhile, the heterojunction structure formed between MSO and SNP accelerated the effective electron transfer. The synergistic effect of the triphase interface structure and electron transfer structure contributed to the high NH3 yield (19.6 ??g h-1 mg -1) and FE (40.34%) of SNP/10MSO in the photo -electrochemical system. Compared with the nanocomposites (SNP/MSI) prepared by hydrophilic MoS2, FE was significantly increased by 10 percentage points.