Electroreduction of CO 2 by Ni sites on nitrogen‐doped carbon aerogels from glucose

Abstract

Electrocatalytic CO2 reduction has offered a promising route for managing the global carbon balance, but presents challenges because of the lack of highly efficient and low-cost electrocatalyst. Compared with the dispersity of metal active sites, the porous structure of the substrate is more significant for the catalytic performance and the design and fabrication of substrate are often the key points and difficulties for electrocatalysts. Herein a facile method to disperse Ni active sites on nitrogen-doped carbon aerogels with high surface area and porosity is reported. Firstly, hydrophilic polysaccharides were prepared by the hydrothermal process of glucose, followed by ultrasonic mixing with Ni complex and melamine. Secondly, calcination was used to increase the surface area and conductivity of the freeze-dried mixture. The Ni/N-C catalyst exhibited good activity with a Faradaic efficiency for CO production of about 95% and a current density of ∼8 mA cm−2 at an overpotential of 750 mV. The result presents helpful guidelines for the rational design and accurate modulation of low-cost and efficient catalysts.