Low-coordination single Ni atoms on graphitic C₃N₄ for nitrite electroreduction to ammonia

Abstract

Electrocatalytic converting NO2- to NH3 (NO2RR) offers an attractive approach to realize both hazardous NO2- abatement and sustainable NH3 production. Single-atom catalysts (SACs) show a great potential for N-cycle electrocatalysis,...

Electroreduction of Nitrite to Ammonia over a Cobalt Single-Atom Catalyst

“…The synthesis of Co 1 /C 3 N 4 is achieved through an impregnation method (Figure 1a). 26 In the X-ray diffraction (XRD) pattern of Co 1 /C 3 N 4 (Figure S1), no distinct diffraction peaks corresponding to Co clusters/particles are observed, suggesting that Co species are highly dispersed on C 3 N 4 . Transmission electron microscopy (TEM) analysis shows that Co 1 /C 3 N 4 has a thin folded nanosheet structure (Figure S2a), and the high-resolution TEM (HRTEM) image shows that Co 1 /C 3 N 4 exists in an amorphous state (Figure S2b), similar to those of pristine C 3 N 4 (Figure S3), indicating that Co species are highly distributed on the C 3 N 4 support.…”

“…The synthesis of Co 1 /C 3 N 4 is achieved through an impregnation method (Figure a) . In the X-ray diffraction (XRD) pattern of Co 1 /C 3 N 4 (Figure S1), no distinct diffraction peaks corresponding to Co clusters/particles are observed, suggesting that Co species are highly dispersed on C 3 N 4 .…”

“…Many catalysts such as precious metals, nonprecious-metal-based compounds, and single-atom catalysts (SACs) have been explored with the NO 2 RR. − Among them, SACs have attracted significant attention as potential NO 2 RR catalysts due to their maximized atom-utilization efficiency . The graphitic carbon nitride (referred to as C 3 N 4 hereafter) is considered an effective SAC support due to its distinctive tertiary amine-like structure, which offers a plethora of nitrogen ligands capable of firmly anchoring metal single atoms.…”

Electrochemical reduction of nitrite to ammonia on amorphous MoO3 nanosheets

“…Diverse precious metals and non-precious metal-based compounds have been experimentally and theoretically explored for NO 2 RR, and their performances have been further improved by several strategies. 17–23 For instance, amorphization has been reported to be an efficient approach for effectively engineering the electronic structures of materials to enhance their catalytic properties. 24–27 Previous reports have demonstrated that amorphization can create abundant structural defects and dangling bonds on the catalyst surface, which can serve as active sites to accelerate ammonia electrosynthesis with high selectivity and activity, 27–29 rendering amorphous materials fascinating catalysts for efficient NO 2 RR.…”

Electrocatalytic reduction of nitrite to ammonia on undercoordinated Cu

“…S8 †), as NO 2 − adsorption is a critical step to trigger the NO 2 RR. 14,39,40 After the MD simulations, it is shown in Fig. 4a that the degree of NO 2 − accumulation on u-Cu is more obvious than that on Cu.…”