Electrocatalytic fixation of N₂ into NO₃⁻: electron transfer between oxygen vacancies and loaded Au in Nb₂O_5−x nanobelts to promote ambient nitrogen oxidation

Abstract

The electrocatalytic nitrogen oxidation reaction (NOR) is a promising alternative to the industrial synthesis of nitrate. However, with the enhancement of the NOR activity by modification methods, the competitive oxygen...

Catalytic Kinetics Regulation for Enhanced Electrochemical Nitrogen Oxidation by Ru‐Nanoclusters‐Coupled Mn3O4 Catalysts Decorated with Atomically Dispersed Ru Atoms

“…After the first work by Zhang et al, [13,14] the electrochemical N 2 oxidation reaction (NOR), using water and N 2 in the atmosphere (78%), has been demonstrated as a sustainable and promising approach for nitric production. [14][15][16][17][18][19][20][21] Electrochemical NOR is an endothermic and entropy-reducing process, [22,23] involving activation of N 2 , adsorption of OH (*OH), and multielectron transfer at "gas-liquid-solid" three-phase interface. This process is hindered by the slow cleavage of the N≡N bond owing to its high bond energy (941 kJ mol −1 ) and insurmountable first-bond dissociation energy (410 kJ mol −1 ).…”

“…In previous studies, OER-inactive catalysts and carriers were served to restrain competitive OER, and gained reasonable performance. [13][14][15][16][17][18][19][20][21] However, simply suppressing OER would reduce the activation of N 2 , the supply of *OH and sacrifice the inherently low activity towards NOR, insufficient to obtain satisfactory performance. Besides, on count of the obvious difference in dynamics between OER and NOR, electron transfer also largely affect the catalytic selectivity.…”

More than a support: the unique role of Nb2O5 in supported metal catalysts for lignin hydrodeoxygenation

“…When lattice oxygen is consumed, oxygen vacancies are created. To create more oxygen vacancies to promote the redox reaction, Zhang et al 36 In addition to the strategy of introducing vacancies in Nb 2 O 5 by some special treatment, its redox ability is also significantly affected by the metal-support interaction. Guan et al 37 found that the reduction temperature of Nb 2 O 5 in supported catalysts was lower than that of the Nb 2 O 5 support, in which the initial H 2 on the metal particles dissociated to form H radical species and then transferred to the surface of the Additionally, the metal-support interaction also affected the content of the different types of oxygen in Nb 2 O 5 .…”

“…When lattice oxygen is consumed, oxygen vacancies are created. To create more oxygen vacancies to promote the redox reaction, Zhang et al 36 used a catalyst annealing treatment and studied the chemical state of Au/Nb 2 O 5 and Au/Nb 2 O 5− x catalysts via XPS analysis. The latter had undergone the annealing treatment, which did not destroy the original lattice structure.…”

Limitations of Electrochemical Nitrogen Oxidation toward Nitrate

“…The difference between oxygen evolution and nitrogen oxidation is shown to highlight the selectivity challenge for nitrogen oxidation. (b) Experimental reported faradaic efficiency and (c) yield of nitrate production for NOR on different materials, like Pd/MXenes, 14 spinel oxide, 15 Ru/TiO 2 , 16 PdO 2 -based, 17 , 18 Pt, 19 Fe/SnO 2 , 20 Au/Nb 2 O 5– x , 21 B 13 C 12 , 22 and Ru–Mn 3 O4 23 against potentials. The gray vertical line indicates the equilibrium potential of NOR toward HNO 3 .…”