Search

Recently, bimetallic nanoparticles (NPs) are promising for driving nitrate (NO3 −) reduction reaction (NO3RR) to produce ammonia (NH3) due to their multiple active sites and electron redistribution via strong metal–metal interaction. However, the quantitatively determining the atomic configuration of the active sites and revealing their respective roles in NO3RR process are still challenged. Herein, the configuration of atomically ordered PdFe3 L12 intermetallic NPs into mesoporous carbon nanofibers (O‐PdFe3‐mCNFs) is reported as an efficient NO3RR catalyst for NH3 synthesis. Compared to the face‐centered cubic one, the O‐PdFe3‐mCNFs demonstrate a high NO3− removal of 98.3% within 270 min with a large NH3 yield rate of 1014.2 µmol h−1 cm−2. The detailed in situ and theoretical analysis reveals that the high performance of O‐PdFe3‐mCNFs is attributed to the synergetic effect from the periodic adjacent Pd‐Fe pair sites at the ordered (110) facet via accelerating proton relay, where the Fe sites show preferable stabilization of nitrogen−oxygen (*NO) intermediates while Pd sites serve as proton reservoir for *NO hydrogenation. Moreover, the strong d‐d orbital hybridization tunes d‐band center of the alloy NPs and effectively modulates the adsorption energy of *NO3− and *NO. This synergetic electrocatalyst design offers a new avenue for developing highly efficient multifunctional NO3RR catalysts. [ABSTRACT FROM AUTHOR]

Electrochemically reducing nitrate (NO3−), a common water pollutant, to valuable ammonia (NH3) offers a green, sustainable, and decentralized route for ammonia synthesis. Electrochemical nitrate reduction reaction (NO3−RR) involves two crucial reaction steps: nitrate deoxygenation followed by nitrite hydrogenation; in particular, the nitrite hydrogenation reaction is the rate‐determining step (RDS) for NO3−RR. In this work, an atomically dispersed cobalt‐phosphorus (Co─P) catalytic pair (CP) with strong electronic coupling is reported. The Co site in Co─P CP effectively activates NO3−, while the P site in Co─P CP facilitates water dissociation to release H+, synergistically enhancing the thermodynamic and kinetic performance of electrochemical nitrate reduction to ammonia. [ABSTRACT FROM AUTHOR]