An Amorphous Noble‐Metal‐Free Electrocatalyst that Enables Nitrogen Fixation under Ambient Conditions

Abstract

N 2 fixation by the electrocatalytic nitrogen reduction reaction (NRR) under ambient conditions is regarded as ap otential approach to achieve NH 3 production, which still heavily relies on the Haber-Boschp rocess at the cost of huge energy and massive production of CO 2 .Anoble-metal-free Bi 4 V 2 O 11 /CeO 2 hybrid with an amorphous phase (BVC-A) is used as the cathode for electrocatalytic NRR. The amorphous Bi 4 V 2 O 11 contains significant defects,w hichp lay ar ole as active sites.The CeO 2 not only serves as atrigger to induce the amorphous structure,but also establishes band alignment with Bi 4 V 2 O 11 for rapid interfacial charge transfer.R emarkably, BVC-A shows outstanding electrocatalytic NRR performance with high average yield (NH 3 :2 3.21 mgh À1 mg À1 cat. ,F aradaic efficiency:1 0.16 %) under ambient conditions,w hich is superior to the Bi 4 V 2 O 11 /CeO 2 hybrid with crystalline phase (BVC-C) counterpart.

Highly Selective Electrochemical Reduction of Dinitrogen to Ammonia at Ambient Temperature and Pressure over Iron Oxide Catalysts

“…Therefore, rational design of the catalyst surfacem ust result in an optimum Na tom binding strength. [46] It has been suggested that the presence of OVs induces modification of the electronic structure of layered double-hydroxide nanosheets and amorphous Bi 4 V 2 O 11 , [47,48] which impactst heir electron transfer to adsorbates,a nd thereby contributes to the N 2 activation and N 2 cleavage. The introduction of more surface OVs on the hematite nanostructure may lead to more active sites for N 2 reduction.R ecently,t he defects were also revisited to act as active centers for other electrocatalytic processes (e.g.,o xygen reduction/evolution reaction).…”

“…[45] On the other hand, theoretical studies revealed that OVs could facilitate N 2 adsorption and N 2 activation by elongating the NNt ripleb ond. [46] It has been suggested that the presence of OVs induces modification of the electronic structure of layered double-hydroxide nanosheets and amorphous Bi 4 V 2 O 11 , [47,48] which impactst heir electron transfer to adsorbates,a nd thereby contributes to the N 2 activation and N 2 cleavage. Therefore, it is reasonable to infer that ah igherc oncentration of OVs on the hematite surface is criticaltothe electrocatalytic reduction of N 2 to NH 3 ,a lthough there is still al ack of mechanistic insights.…”

High‐Performance Electrocatalytic Conversion of N2 to NH3 Using Oxygen‐Vacancy‐Rich TiO2 In Situ Grown on Ti3C2Tx MXene

“…Before NRR test, Nafion membrane was protonated following the previous reports [6] (more detailed description can be found in the Supporting Information). The electrochemical NRR tests were performed using an H-cell system that was isolated by Nafion 211 membrane.…”

“…[49] All these results confirmed the co-existence of anatase TiO 2 and Ti 3 C 2 T x nanosheets in the astreated samples, which was defined as TiO 2 /Ti 3 C 2 T x accordingly. [6,25] The morphologies and structures of the Ti 3 C 2 T x and TiO 2 / Ti 3 C 2 T x were characterized by the transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques, respectively. Figure 1E-G shows a comparison of the XPS analysis of Ti, C, and O from the two samples.…”

Oxygen‐Doped Porous Carbon Nanosheet for Efficient N2 Fixation to NH3 at Ambient Conditions

“…Previous studies have proved that noble‐metal based catalysts are efficient N 2 reduction reaction (NRR) electrocatalysts, but their large‐scale uses are severely limited by the high cost and rareness. Considerable recent attention has thus focused on earth‐abundant transition metal‐based alternatives to effectively catalyze the NRR . Nevertheless, metal ions may be released from such catalysts, leading to environmental pollution.…”