Selective Electrochemical Conversion of N₂ to NH₃ in Neutral Media Using B, N-Containing Carbon with a Nanotubular Morphology

Abstract

Electrochemical dinitrogen reduction (NRR) has riveted substantial attention as a greener method to synthesize ammonia (NH 3 ) under ambient conditions. Here, B, N-containing carbon catalysts with a discrete morphology were synthesized from the metal−organic framework-ionic liquid (MOF-IL) composite for NRR in a neutral electrolyte medium (pH = 7). Morphologydependent activity is witnessed, wherein C-BN@600 with a nanotubular morphology is able to achieve a high NH 3 yield rate of 204 μg h −1 mg cat −1 and an F.E. of 16.7% with a TOF value of 0.2 h −1 at −0.2 V vs RHE. Further, a rigorous protocol is put forward for true NH 3 estimation by tracing/eliminating any source of contamination in catalysts, electrolytes, or gas supply via ultraviolet−visible (UV−vis) spectroscopy, gas-purification methods, and isotope labeling experiments. Density functional theory predicts BN to be the favorable active site for N 2 adsorption with a reduced energy barrier in the first reduction step and sequential stabilization of the B−N bond by an adjacent carbon atom.

Glucose oxidation assisted ammonia production via electrochemical dinitrogen reduction over CoWO4

“…Lastly, the gas-supplies were already passed through a purication set-up before NRR investigations to ensure the elimination of N-contaminations. 22 In addition to this, other control experiments were performed including the NRR at open circuit potential (OCP) and over bare electrode surfaces and the response of catalysts towards the NRR under Ar-saturated conditions was evaluated as well (Fig. S17, ESI †).…”

“…15 Thus, economic and earth-abundant transition metal-based electrocatalysts such as metal sulfides, 16,17 metal nitrides, 18,19 metal oxides, 20 etc. 21,22 have been reported. Despite encouraging progress in the field, it still remains desirable to develop highly efficient catalysts towards the NRR.…”

Self-powered NH3 synthesis by trifunctional Co2B-based high power density Zn–air batteries

“…[25][26][27][28] However, so far, only three reports are available wherein ZABs have been used to power electrochemical NH 3 synthesis. 12,29,30 Several classes of catalysts, including noblemetal-based, [31][32][33] non-noble metal-based 34,35 and metal freebased catalysts, [36][37][38] have been explored towards NRR in aqueous media, but the faradaic efficiency (F.E.) and NH 3 production yield rate obstruct their attempt to be put into practice.…”

Theory-Guided Construction of the Unsaturated V–N2 Site with Carbon Defects for Highly Selective Electrocatalytic Nitrogen Reduction

“…), and the central elements are normally transition metals (such as Mo, 22 Fe, 23 or Nb 24 ). By ligation with heteroatoms (such as N, 25 O, 26 B, 27 or F, 28 ), a unique coordination environment thus forms. The synergistic effect of the electron distribution between the metal center and its coordination environment may afford favorable electronic structures for the adsorption and activation of nitrogen, thereby improving the NRR performance.…”