High-efficiency electrocatalytic NO reduction to NH₃by nanoporous VN

Abstract

Electrocatalytic NO reduction reaction to generate NH 3 under ambient conditions offers an attractive alternative to the energy-extensive Haber-Bosch route; however, the challenge still lies in the development of cost-effective and high-performance electrocatalysts. Herein, nanoporous VN film is first designed as a highly selective and stable electrocatalyst for catalyzing reduction of NO to NH 3 with a maximal Faradaic efficiency of 85% and a peak yield rate of 1.05 × 10 -7 mol•cm -2 •s -1 (corresponding to 5,140.8 g•h -1 •mg cat.-1 ) at -0.6 V vs. reversible hydrogen electrode in acid medium. Meanwhile, this catalyst maintains an excellent activity with negligible current density and NH 3 yield rate decays over 40 h. Moreover, as a proof-of-concept of Zn-NO battery, it delivers a high power density of 2.0 mW•cm -2 and a large NH 3 yield rate of 0.22 × 10 -7 mol•cm -2 •s -1 (corresponding to 1,077.1 g•h -1 •mg cat.-1 ), both of which are comparable to the best-reported results. Theoretical analyses confirm that the VN surface favors the activation and hydrogenation of NO by suppressing the hydrogen evolution. This work highlights that the electrochemical NO reduction is an eco-friendly and energy-efficient strategy to produce NH 3 .

Metal-coordinated porous polydopamine nanospheres derived Fe 3N-FeCo encapsulated N-doped carbon as a highly efficient electrocatalyst for oxygen reduction reaction

“…Galvanostatic discharge measurements (Figure 5d) indicate that Fe3N-FeCo@NC-based device displays the potential plain at 1.372 V, 1.333 V, 1.301 V and 1.251 V at discharge current densities of 2, 5, 10 and 20 mA cm -2 , respectively, and the negligible voltage drop is observed for 2 h. The discharge potential is nearly recovered when a 2 mA cm -2 current is applied again, indicating the excellent rate capability. [35] The Fe3N-FeCo@NC-based Zn-air battery also exhibits a larger specific capacity (806.6 mA h g −1 Zn) at 5 mA cm -2 than Pt/C (660.56 mA h g −1 Zn) counterpart (Figure 5e). Notably, there is no obvious potential drop under galvanostatic discharge for 110 h at 5 mA cm −2 , corroborating the superior stability toward ORR catalysis (Figure 5f).…”

Oxygen Vacancy-Rich Amorphous Copper Oxide Enables Highly Selective Electroreduction of Carbon Dioxide to Ethylene

“…4a). Commercial IrO2-coated Ti foam was employed as the anode to drive the oxygen evolution reaction [56][57][58][59][60] . The anionexchange membrane was used to separate the cathodic from the anodic compartment.…”

Co Nanoparticles Decorated Corncob-Derived Biomass Carbon as an Efficient Electrocatalyst for Nitrate Reduction to Ammonia

“…In 0.1 M NaOH with 0.1 M NO 3 – , Co@CC is able to provide a remarkable NH 3 yield of 0.60 mmol h –1 cm –2 and a FE of up to 93.4% at −0.8 V, with robust electrochemical durability for eight recycling tests and long-time electrolysis. Our research not only offers a highly efficient electrocatalyst for ambient NH 3 synthesis via NO 3 – reduction but also provides an exciting new way for the rational development of corncob-derived nanocarbon as a support for nanocatalysts toward selective electroreduction of nitrogenous pollutants − into highly value-added NH 3 .…”