摘要
Eco-friendly ammonia (NH3) production is critical for advancing sustainable agriculture and industry. This study introduces a sustainable, cleaner approach using MoS2 nanoflowers (NFs) to synthesize NH3 directly from water and air without the need for sacrificial agents. The advanced design leverages double sulfur vacancies (V2s) in MoS2 NFs (V2s-MoS2 NFs) and their piezoelectric properties, achieving a noteworthy production efficiency of 8374.8 +/- 140.1 mu mol L-1 g(-1) h(-1) (absolute production rate of 0.84 +/- 0.01 mu mol h(-1)). This outperforms most existing photocatalysts and piezocatalysts and rivals advanced electrocatalysts. The catalyst demonstrated exceptional stability, producing 36.55 mmol L-1 g(-1) (equivalent to an absolute yield of 3.655 mu mol) with N-2 and 26.03 mmol L-1 g(-1) (equivalent to an absolute yield of 2.603 mu mol) with air over 8 h. In situ Raman spectroscopy revealed intensifying peaks at similar to 819 and 993 cm(-1) under N-2 gas, attributed to Mo-N stretching vibrations. Additionally, in situ diffuse reflectance infrared Fourier-transform spectroscopy showed N-2 adsorption configurations, including side-on adsorption, indicative of N equivalent to N bond elongation on the catalyst surface. Density functional theory calculations corroborated these findings, illustrating how unpaired Mo d orbital electrons near sulfur vacancies activate N-2 dissociation via backdonation to N-2's antibonding pi orbitals. This research highlights the transformative potential of piezocatalytic systems for nitrogen reduction reactions using atmospheric N-2 and water, providing a basis for sustainable energy solutions.