Construction of a Novel Hydrogen-Bond-Assisted Bisulfide Nonmetallic Active Center for Solar Ammonia Fertilizer Production

Abstract

Solar-driven photocatalytic nitrogen reduction is a promising and effective way to produce NH 3 in a sustainable manner. The reaction product, ammonium-based nitrogen, can mimic biological nitrogen fixation for plant growth and replace the use of exogenous nitrogen fertilizers. To address the bottleneck of N 2 activation during N 2 reduction, nitrogen fixation catalyst dithiosalicylic acid (DTSA) with a hydrogen-bond-assisted S−S nonmetallic active center was constructed by thiosalicylic acid in this study, which achieved an ammonia yield of 278.9 μmol/h/g cat. .The innovative application of the catalytic product as a replacement fertilizer for the growth of Chlorella resulted in a significant increase in the concentration of Chlorella without yellowing of the algal filaments compared to the blank control group, indicating an adequate supply and functioning of nitrogen fertilizers. Further mechanistic studies reveal an alternating reaction pathway for nitrogen at the S−S active center. The energy barrier of the rate-determining step (RDS) is effectively reduced from 2.79 to 2.11 eV with the aid of intermolecular hydrogen bonding of DTSA. The catalyst is controllable in mass production and simple in synthesis, and the catalytic product is used in the cultivation of Chlorella as an opportunity for the development of NRR catalysts for solar nitrogen fertilizers. Furthermore, the proposed novel active center provides a new idea and direction for the development of future catalysts.