Sulfur dots–graphene nanohybrid: a metal-free electrocatalyst for efficient N₂-to-NH₃ fixation under ambient conditions

Abstract

Sulfur dots–graphene nanohybrids act as an efficient electrocatalyst for the conversion of N2 to NH3 in 0.5 M LiClO4, achieving a high NH3 yield of 28.56 μg h−1 mgcat.−1 and a Faradaic efficiency of 7.07% at −0.85 V vs. RHE.

Transition Metal‐dinitrogen Complex Embedded Graphene for Nitrogen Reduction Reaction

“…Recently, the electrochemical conversion nitrogen to ammonia can be carried out under ambient conditions. [11][12][13][14][15][16][17][18][19][20][21][22][23][24] During this process, the nitrogen molecule in air and the water is used as the nitrogen source and proton source, respectively. The whole catalytic process needs six protons and six electrons, which follows the three possible pathways: distal, alternating and enzyme mechanisms.…”

Nitrogen‐Doped NiO Nanosheet Array for Boosted Electrocatalytic N2 Reduction

“…[1] However, the current NH 3 production relies dominantly on the Haber-Bosch Process (N 2 + 3H 2 !2NH 3 ) under harsh conditions (350~550°C, 2003 00 bar) [2] , giving rise to the enormous energy consumption and huge CO 2 emissions. Therefore, it is urgently required to explore energy-saving, yet efficient technological routes for artificial N 2 fixation.Electrochemical NH 3 synthesis (N 2 + 3H 2 O!2NH 3 + 3/2O 2 ), derived from N 2 and H 2 O and powered by renewable electricity, provides a sustainable and scalable approach for N 2 fixation at ambient conditions [3][4][5][6][7] . To achieve favorable N 2 -to-NH 3 conversion, a prerequisite is to develop highly active and robust electrocatalysts that can effectively activate N 2 reduction reaction (NRR) and realize both high NH 3 yield and Faradaic efficiency (FE) at relatively low potentials [8][9][10][11] .…”

“…Electrochemical NH 3 synthesis (N 2 + 3H 2 O!2NH 3 + 3/2O 2 ), derived from N 2 and H 2 O and powered by renewable electricity, provides a sustainable and scalable approach for N 2 fixation at ambient conditions [3][4][5][6][7] . To achieve favorable N 2 -to-NH 3 conversion, a prerequisite is to develop highly active and robust electrocatalysts that can effectively activate N 2 reduction reaction (NRR) and realize both high NH 3 yield and Faradaic efficiency (FE) at relatively low potentials [8][9][10][11] .…”

Recent Advances in Noble‐Metal‐Free Catalysts for Electrocatalytic Synthesis of Ammonia under Ambient Conditions

“…[97] Chen et al reported a sulfur dots-graphene nanohybrid (Figure 4d, 4e), achieving excellent performance in NRR. [98] Tian et al first applicated N, S co-doped graphene (NSG) as an efficient metal-free NRR catalyst, exhibiting a high NH 3 yield of 7.7 μg h À 1 mg cat À 1 and a FE of 5.8% at À 0.6 V, since the N, S co-doping could effectively improve the catalyst performance by promoting the N 2 adsorption and N � N bond elongation, boosting the electron transfer and creating more active sites. [99] Zhao et al first fabricated oxidized carbon nanotube material (OÀ CNT) ( Figure 4f-4h) by chemical method, which showed a large NH 3 yield of 32.33 μg h À 1 mg cat À 1 and a high FE of 12.50% at À 0.4 V, due to the vital role of CÀ O groups in the electrochemical fixation of N 2 .…”