Isolated Electron‐Rich Ruthenium Atoms in Intermetallic Compounds for Boosting Electrochemical Nitric Oxide Reduction to Ammonia

Abstract

The direct electrochemical nitric oxide reduction reaction (NORR) is an attractive technique for converting NO into NH 3 with low power consumption under ambient conditions. Optimizing the electronic structure of the active sites can greatly improve the performance of electrocatalysts. Herein, we prepare body-centered cubic RuGa intermetallic compounds (i.e., bcc RuGa IMCs) via a substrate-anchored thermal annealing method. The electrocatalyst exhibits a remarkable NH 4+ yield rate of 320.6 μmol h À 1 mg À 1 Ru with the corresponding Faradaic efficiency of 72.3 % at very low potential of À 0.2 V vs. reversible hydrogen electrode (RHE) in neutral media. Theoretical calculations reveal that the electron-rich Ru atoms in bcc RuGa IMCs facilitate the adsorption and activation of *HNO intermediate. Hence, the energy barrier of the potentialdetermining step in NORR could be greatly reduced.

Multicomponent catalyst design for CO2/N2/NOxelectroreduction

“…In addition, electroreduction of other NO x molecules, such as NO (x=1) and NO 2 -(x=2) to NH 3 was also reported but will not be discussed in the current review. [25][26][27][28]…”

“…In addition, electroreduction of other NO x molecules, such as NO (x = 1) and NO 2 − (x = 2), to NH 3 has been also reported but will not be discussed in the current review. [25][26][27][28] 3 Emerging multicomponent catalysts Multicomponent catalysts, as the name implies, have at least two components, but it is worth noting that not all the components in a multicomponent catalyst act as catalytic sites for catalytic reactions. The main characteristic of a type I…”

Amorphous NiB2for electroreduction of NO to NH3

“…[17][18][19][20][21] Nevertheless, the complex ve-electron process and HER competition greatly compromise the NORR efficiency. [22][23][24] Thus, developing high-performing catalysts for concurrently promoting the NORR and inhibiting the HER is urgently required. [25][26][27][28][29] Transition metal diboride (TMB 2 )-based materials (TiB 2 , ZrB 2 , FeB 2 , MoB 2 , etc.)…”

“…17–21 Nevertheless, the complex five-electron process and HER competition greatly compromise the NORR efficiency. 22–24 Thus, developing high-performing catalysts for concurrently promoting the NORR and inhibiting the HER is urgently required. 25–29…”

Main-group indium single-atom catalysts for electrocatalytic NO reduction to NH3

“…Diverse transition metal-based materials have been reported as active NORR catalysts, [26][27][28][29] by virtue of their partially occupied d-orbitals to enhance NO adsorption and dissociation. Nonetheless, d-orbitals also contribute to *H binding on the catalyst surface, which is benecial for the competitive HER and unfavorable for FE NH 3 .…”