Strategic Structure Tuning of Yolk‐Shell Microcages for Efficient Nitrogen Fixation

Abstract

The electrocatalytic nitrogen reduction reaction (ENRR) under ambient conditions is considered as a promising process to produce ammonia. Towards highly efficient catalysts, here an optimized one‐step pyrolysis strategy was tailored to design yolk–shell microcages (YS Co@C/BLCNTs), consisting of Co nanocrystals encapsulated in N‐doped carbon framework and bridged by bamboo‐like carbon nanotubes (BLCNTs). The cavity created between yolk and shell not only served as a “micro‐bag” to store the reactant N2 and enhance its dissolution, but also induced a “cage effect” to confine the diffusion of reaction intermediate, hence making the reaction proceed in the direction of producing NH3. This catalyst displayed excellent catalytic activities for ENRR: a high NH3 yield of 12.87 μg mgcat−1 h−1 at a high faradaic efficiency of 20.7 % at −0.45 V (vs. reversible hydrogen electrode, RHE). After 5 cycles of consecutive ENRR process, the NH3 yield rate was 11.29 μg mgcat−1 h−1, indicating the excellent electrocatalytic stability. These results provide a structural engineering for ENRR catalyst with doped N, cooperating with non‐precious metal to activate the inert triple bond of N2 and achieve NH3 fixation.

Intersperse copper nanoparticles into 3D fibrous silica-supported carbon spheres for electrocatalytic nitrogen reduction

“…4a). Over a wide potentail range of − 1.0 to − 0.4 V vs. RHE, the current density in N 2 saturation was higher than that in Ar saturation, indicating active e-NRR performance in N 2 [40]. The standard curve method was made and used to measure the electrolysis products (Fig.…”