NiWO₄nanoparticles with oxygen vacancies: high-efficiency electrosynthesis of ammonia with selective reduction of nitrite

Abstract

Electrochemical reduction of nitrite (NO2−RR) is a promising research direction for removing environmental pollutants NO2− from wastewater and generating value-added ammonia (NH3). However, NO2−RR kinetic reactivity is slow and requires...

An Amorphization-Engineered Catalyst for Electrocatalytic Reduction of Nitric Oxide to Ammonia

“…As depicted in Figure a, a-FeS 2 displays a notably higher LSV current density in NO-saturated solution with respect to Ar one, signifying the excellent reactivity of a-FeS 2 toward the NORR. Next, we quantitatively evaluate the NORR property of a-FeS 2 by combining chronoamperometry and colorimetric methods. − Figure b illustrates a distinctive volcano-like pattern in both NH 3 yield rate and FE NH3 , with the peak FE NH3 of 92.5% and corresponding NH 3 yield rate of 227.1 μmol h –1 cm –2 at −0.6 V. By comparing the performance of a-FeS 2 with catalysts previously reported (Figure c), it is apparent that a-FeS 2 stands out as one of the most efficient catalysts for the NORR. The pronounced reduction in NORR activity at −0.7 V is predominantly ascribed to the intensified competition from the HER .…”

ZnFe2O4 nanosheet array: a highly efficient electrocatalyst for ambient ammonia production via nitrite reduction

“…Ammonia (NH 3 ), an essential chemical widely recognized by human society, finds extensive applications in cosmetics, fertilizers, disinfectants and dyes, and it also holds the potential as a green energy carrier for its remarkable energy density of 4.3 kW h kg −1 . 1–6 To date, the Haber–Bosch process (HBP) remains the dominant method for ammonia (NH 3 ) synthesis. However, the HBP's demanding production conditions involving high temperatures and pressures have led to significant fossil energy consumption and the release of substantial CO 2 emissions.…”

Recent Advances in Electrocatalysts for Sustainable Electrosynthesis of Ammonia and Urea from Ambient Nitrite Reduction and C–N Coupling

“…Transition metal oxides (TMOs) feature low cost, environmentally friendliness, and high activity. Especially, ternary transition metal oxides with two different metal cations possessing oxidation state diversity have also been used for NO 2 RR. − Because of the multivalent state of W, Qiu et al chose NiWO 4 as a model catalyst . The generation of OVs on the bridge O between W and Ni atoms achieves charge redistribution and effectively facilitates NO 2 – adsorption and activation, thereby enhancing NO 2 RR activity (Figure i,j).…”

“…115−118 Because of the multivalent state of W, Qiu et al chose NiWO 4 as a model catalyst. 119 The generation of OVs on the bridge O between W and Ni atoms achieves charge redistribution and effectively facilitates NO 2 − adsorption and activation, thereby enhancing NO 2 RR activity (Figure 4i,j). The NH 3 yield of the proof-of-concept catalyst is 10 974.36 μg h −1 cm −2 at −0.4 V vs RHE, with a Faradaic efficiency of 97.6% in 0.1 M NaOH + 0.1 M NO 2 − .…”

“…(j) Difference of charge density on NiWO 4– x (002) with NO 2 – adsorption. Reprinted with permission from ref . Copyright 2023 Royal Society of Chemistry.…”