Cu@g-C₃N₄: An Efficient Single-Atom Electrocatalyst for NO Electrochemical Reduction with Suppressed Hydrogen Evolution

Abstract

Nitric oxide electroreduction reaction (NOER) is one of the most attractive routes for ammonia synthesis and pollutant treatment. However, the current research efforts toward the NOER mainly focus on metal surface catalysts, while low-cost and high-efficiency single-atom catalysts (SACs) are rarely explored. Herein, using first-principles computations, we systematically investigate the NOER performance of a series of transition-metal-atomdecorated graphitic carbon nitride monolayer (g-C 3 N 4 ) and identify single Cu-atomdecorated g-C 3 N 4 (Cu@g-C 3 N 4 ) as the most promising SAC candidate for the NOER. Our results indicate that Cu@g-C 3 N 4 harbors excellent catalytic activity for the NOER with a quite low limiting potential of 0.371 V and, interestingly, is promising to be synthesized due to extremely high stability. Most importantly, Cu@g-C 3 N 4 can efficiently suppress the competing hydrogen evolution reaction, in favor of achieving high Faradaic efficiency. Our work provides a promising SAC candidate for the NOER to resolve environmental pollution and sustainable ammonia production.

Efficient nitric oxide electroreduction toward ambient ammonia synthesis catalyzed by a CoP nanoarray

“…3,9 Notably, ambient NO reduction by electrocatalysis is being investigated as a sustainable approach for NO hydrogenation to other harmless or valuable nitrogen species, using only water and electrical energy. [10][11][12][13][14][15][16][17][18][19][20][21][22][23] Among these products, NH 3 as a critical chemical for producing fertilizers and a potential carbon-free energy carrier with high energy density is a notable target molecule. 24,25 Although NH 3 can be produced by N 2 electroreduction, [26][27][28][29] it is extremely challenging from both thermodynamic and kinetic points of view since N 2 is chemically inert and poorly dissolves in water.…”

Electrochemical reduction of NO catalyzed by boron-doped C60 fullerene: a first-principles study

“…The corresponding U L value is much lower than that of the NOER on the B-graphene, 71 Si–N 4 /graphene, 28 Co–N 4 /graphene 70 and Cu decorated g-C 3 N 4 . 72 Furthermore, a comparison of the P2-1 and P2-2 routes indicates that the Δ G and Δ E values due to the formation of *H 2 NO (+0.07 and −0.33 eV) are significantly smaller than those of *HNOH (−0.31 and −0.68 eV); hence, formation of the *HNOH is more favorable from an energy viewpoint.…”

“…22 and 23) reduction or hydrogen evolution reaction (HER). 24,25 Numerous studies [26][27][28] based on density functional theory (DFT) have also demonstrated the potential of such SACs for electrochemical NO molecule reduction. Wang et al 26 investigated the NO binding on various TM doped nitrogen incorporated graphene (TM ¼ Sc-Cu, Mo, Rh, and Ru) and found that the Co atom is the most suitable SAC for the reduction of NO.…”

Direct Synthesis of Atomically Dispersed Palladium Atoms Supported on Graphitic Carbon Nitride for Efficient Selective Hydrogenation Reactions

“…To solve this problem, an effective strategy is needed to introduce strong anchoring sites into the 2D support. Recently, 2D graphitic carbon nitride (g-C 3 N 4 ) has been demonstrated to show exceptional catalytic activity because of its unique band gap, Lewis base properties, and high specific surface area. ,,− The triazine units within g-C 3 N 4 offer abundant and uniform nitrogen-containing anchoring sites that effectively confine metal ions to form well-defined active sites. − For example, Dai et al synthesized Cu single atoms supported on a g-C 3 N 4 electrocatalyst, using it for NO electrochemical reduction . Li et al reported a Au 1 /C 3 N 4 SAC for acetylene hydrochlorination with excellent catalytic performance .…”