Nanoporous Intermetallic Pd₃Bi for Efficient Electrochemical Nitrogen Reduction

Abstract

Electrocatalytic nitrogen reduction at ambient temperature is a green technology for artificial nitrogen fixation but greatly challenging with low yield and poor selectivity. Here, a nanoporous ordered intermetallic Pd3Bi prepared by converting chemically etched nanoporous PdBi2 exhibits efficient electrocatalytic nitrogen reduction under ambient conditions. The resulting nanoporous intermetallic Pd3Bi can achieve high activity and selectivity with an NH3 yield rate of 59.05 ± 2.27 µg h−1 mgcat−1 and a Faradaic efficiency of 21.52 ± 0.71% at −0.2 V versus the reversible hydrogen electrode in 0.05 m H2SO4 electrolyte, outperforming most of the reported catalysts in electrochemical nitrogen reduction reaction (NRR). Operando X‐ray absorption spectroscopy studies combined with density functional theory calculations reveal that strong coupling between the Pd–Bi sites bridges the electron‐transfer channel of intermetallic Pd3Bi, in which the Bi sites can absorb N2 molecules and lower the energy barrier of *N2 for N2 adsorption and activation. Meanwhile, the intermetallic Pd3Bi with bicontinuous nanoporous structure can accelerate the electron transport during the NRR process, thus improving the NRR performance.

Interfacial Engineering Enhances the Electroactivity of Frame‐Like Concave RhCu Bimetallic Nanocubes for Nitrate Reduction

“…The fact indicates high NH 3 yield of NO 3 − ‐RR at PA‐RhCu cNCs originates from the KNO 3 electroreduction rather than N‐containing pollution species in the experimental environment. [ 55,56 ] Furthermore, it is observed that the NH 3 yield and faradaic efficiency of NH 3 for NO 3 − ‐RR at PA‐RhCu cNCs at 0.05 V applied potential are much higher than most reported values at various electrocatalysts (Table S1, Supporting Information), [ 29,44–52 ] proving the high NO 3 − ‐RR activity of PA‐RhCu cNCs. Obviously, the high apparent NO 3 − ‐RR activity of PA‐RhCu cNCs directly benefits from the high ECASA derived from the unusual frame‐like concave nanocube structure with hollow, pore‐like and dendritic features.…”

“…− -RR at PA-RhCu cNCs originates from the KNO 3 electroreduction rather than N-containing pollution species in the experimental environment. [55,56] Furthermore, it is observed that the NH 3 yield and faradaic efficiency of NH 3 for NO 3…”

Molecular Crowding Effect in Aqueous Electrolytes to Suppress Hydrogen Reduction Reaction and Enhance Electrochemical Nitrogen Reduction

“…Currently, the vast majority of works focus on the design of catalysts with special structures and compositions to improve NH 3 activity and selectivity, such as introducing doping heteroatoms or atomic vacancies, adopting supporters with low HER activity. [ 8,14–20 ] Nonetheless, such strategies for achieving efficient catalysts with both high activity and selectivity are rather challenging. [ 10,14,21,22 ] In terms of aqueous electrolytes, the proton‐poor neutral/alkaline solutions are generally used to lower the H + accessibility for a suppressed HER, [ 23–27 ] but they cannot broaden the potential gap between NRR and HER (Figure S1).…”

Atomically Dispersed Manganese Lewis Acid Sites Catalyze Electrohydrogenation of Nitrogen to Ammonia

“…Ammonia is an essential platform chemical to the global economy and plays key roles in industry, agriculture and pharmaceutical chemistry. [1][2][3][4] It is also a preferred carbon neutral energy carrier for sustainable energy storage with a 17.6 wt% hydrogen content and a high energy density of 4.3 kW h -1 . [5][6][7] Dinitrogen reduction for ammonia is a vital step in the natural nitrogen cycle.…”