Achieving a Record‐High Yield Rate of 120.9 for N₂ Electrochemical Reduction over Ru Single‐Atom Catalysts

Abstract

The electrochemical reduction of N into NH production under ambient conditions represents an attractive prospect for the fixation of N . However, this process suffers from low yield rate of NH over reported electrocatalysts. In this work, a record-high activity for N electrochemical reduction over Ru single atoms distributed on nitrogen-doped carbon (Ru SAs/N-C) is reported. At -0.2 V versus reversible hydrogen electrode, Ru SAs/N-C achieves a Faradaic efficiency of 29.6% for NH production with partial current density of -0.13 mA cm . Notably, the yield rate of Ru SAs/N-C reaches 120.9 μgNH3 mgcat.-1 h-1, which is one order of magnitude higher than the highest value ever reported. This work not only develops a superior electrocatalyst for NH production, but also provides a guideline for the rational design of highly active and robust single-atom catalysts.

Tuning the Catalytic Preference of Ruthenium Catalysts for Nitrogen Reduction by Atomic Dispersion

“…Figure 2b shows the XPS spectra of the C 1s for Ru SAs/g-C 3 N 4 and pure g-C 3 N 4 , and only one strong peak appeared at 287.4 eV in pure g-C 3 N 4 , which can be assigned to the sp 2 -hybridized carbon in NCN. [9] These results confirm the absence of crystalline Ru in Ru SAs/g-C 3 N 4 , and that Ru atoms in Ru SAs/g-C 3 N 4 are atomically dispersed. [22] In addition, for Ru SAs/g-C 3 N 4 , a doublet at 280.9 and 285.1 eV was identified, which agreed well with the 3d 5/2 and 3d 3/2 electrons of Ru ions in Ru-N moieties, indicating that Ru ions were successfully incorporated into the g-C 3 N 4 matrix via Ru-N coordination bonds.…”

“…[7] This process takes place under harsh conditions (about 450 °C and 300 bar), is energy intensive, and emits massive amounts of greenhouse gases. [9] Moreover, it has added benefits, such as modularity, scalability, and on-site, on-demand generation, which enables ammonia production in remote areas. In addition, the utilization of aqueous electrolytes has the potential of achieving the simplicity and low cost of this process, because the solvent water can directly serve as the hydrogen source.…”

“…In addition, the utilization of aqueous electrolytes has the potential of achieving the simplicity and low cost of this process, because the solvent water can directly serve as the hydrogen source. [9,11] So far, a variety of single-atom electrocatalysts for NRR has been reported, including Ru single atoms distributed on nitrogendoped carbon which shows a high and stable NH 3 production rate of 3.665 mg NH3 h −1 mg Ru −1 at −0.21 V versus RHE, [11a] single Mo atoms anchored to nitrogen-doped porous carbon which achieves an NH 3 yield rate (34.0 µg mg cat −1 h −1 ) with the FE of 14.6% at −0.3 V versus RHE, [11b] and Au single sites stabilized on hierarchical nitrogen-doped porous noble carbon which affords a stable NH 3 yield of 2.32 µg h −1 with the FE of 12.3% at −0.20 V versus RHE. [10] Dispersion of metal in the form of single or a few metal atoms as actives sites on a suitable substrate could be an effective strategy to achieve facile ammonia synthesis.…”

Channel‐Rich RuCu Nanosheets for pH‐Universal Overall Water Splitting Electrocatalysis

“…[7][8][9][10] Iridium-based and platinumbased electrocatalysts exhibit good performance in OER and hydrogen evolution reaction (HER), respectively,w hile the demerits including scarcity and high cost still limit their largescale practical applications. [15,16] Significantly,i th as also been shown that Ru-based electrocatalysts are active in both HER and OER. [15,16] Significantly,i th as also been shown that Ru-based electrocatalysts are active in both HER and OER.…”

Atomically Dispersed Molybdenum Catalysts for Efficient Ambient Nitrogen Fixation

“…[1][2][3][4] From an energy-saving perspective,g reen N 2 to NH 3 fixation methods are strongly desired because the main industrial process for producing NH 3 -the Haber-Bosch process-requires extremely harsh reaction conditions (400-600 8 8C, 20-40 MPa) and causes pollution and greenhouse gas emissions. [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] However,t he efficiency of the NRR suffers from ap arallel hydrogen evolution reaction (HER) in aqueous solutions on traditional NRR electrocatalysts. [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] However,t he efficiency of the NRR suffers from ap arallel hydrogen evolution reaction (HER) in aqueous solutions on traditional NRR electrocatalysts.…”