Bi2S3 quantum dots in situ grown on MoS2 nanoflowers: An efficient electron-rich interface for photoelectrochemical N2 reduction

Photoelectrocatalysis is considered a green, environmentally friendly, sustainable technology for NH3 synthesis. However, the low efficiency of ammonia synthesis is currently the primary problem in photoelectrochemical nitrogen reduction reactions (PEC NRR). Herein, a nanocomposite BQD/MS developed through the in-situ growth of Bi2S3 quantum dots (BQD) on MoS2 (MS) nanoflowers was demonstrated as an efficient PEC NRR catalyst. Experimental results showed that the strong interaction between BQD and MS modulated the interfacial charge distribution and increased the electron density on the MS side. Meanwhile, the excellent structure of BQD/MS promoted the effective migration of photogenerated electrons from excited BQD to the MS surface. The electron-rich MS reaction interface was conducive to cleaving the stable NN bond and improving the N2 reduction performance. As a result, the prepared BQD/15MS photocathode obtained an excellent Faradaic efficiency of 33.2% and an NH3 yield of 18.5 μg h-1 mg-1, which was about three times that of bare MS.