Dendritic Cell‐Inspired Designed Architectures toward Highly Efficient Electrocatalysts for Nitrate Reduction Reaction

Abstract Electrocatalysis for nitrate reduction reaction (NRR) has recently been recognized as a promising technology to convert nitrate to nitrogen. Catalyst support plays an important role in electrocatalytic process. Although porous carbon and metal oxides are considered as common supports for metal‐based catalysts, fabrication of such architecture with high electric conductivity, uniform dispersion of nanoparticles, and long‐term catalytic stability through a simple and feasible approach still remains a significant challenge. Herein, inspired by the signal transfer mode of dendritic cell, an all‐carbon dendritic cell‐like (DCL) architecture comprising mesoporous carbon spheres (MCS) connected by tethered carbon nanotubes (CNTs) with CuPd nanoparticles dispersed throughout (CuPd@DCL‐MCS/CNTs) is reported. An impressive removal capacity as high as 22 500 mg N g −1 CuPd (≈12 times superior to Fe‐based catalysts), high nitrate conversion (>95%) and nitrogen selectivity (>95%) are achieved under a low initial concentration of nitrate (100 mg L −1 ) when using an optimized‐NRR electrocatalyst (4CuPd@DCL‐MCS/CNTs). Remarkably, nitrate conversion and nitrogen selectivity are both close to 100% in an ultralow concentration of 10 mg L −1 , meeting drinking water standard. The present work not only provides high electrocatalytic performance for NRR but also introduces new inspiration for the preparation of other DCL‐based architectures.