Hierarchical monolithic carbon with high transfer performance for hydrogen evolution reaction

Abstract

Electrocatalysis is an efficient green process for energy conversion. However, for gas-related electrocatalytic reaction, sluggish gas transport has inhibited significantly the promotion of electrocatalytic performances. Herein, hierarchical monolithic material 3DPC-650 and 3DPC-650@Ni/Ni(OH)2 were prepared by 3D printing polyethyleneimine cross-linking oxygenated carbon nanotube and following nickel electrodeposition. 3DPC-650 and 3DPC-650@Ni/Ni(OH)2 have regular pore structure in consistence with 3D printing design and uniform dispersed elements. Amide bonds and carbon defects are presented on the surface of 3DPC-650 and 3DPC-650@Ni/Ni(OH)2 as well as uniformly distributed β-Ni(OH)2 on 3DPC-650@Ni/Ni(OH)2. 3DPC-650 and 3DPC-650@Ni/Ni(OH)2 present lower overpotentials of 322 and 160 mV for hydrogen evolution reaction in 1.0 M KOH at 50 mA cm−2, respectively. The ordered channel, high turnover frequency and electrochemically active surface area, hydrophilic and aerophobic properties result in the higher performance of 3DPC-650 and 3DPC-650@Ni/Ni(OH)2 than traditional supports (carbon paper, carbon cloth, and nickel foam) and electrocatalysts. This work provides an efficient pathway for design and preparation of the monolithic electrocatalyst and electrode used for electrochemical reactions where gas is involved.