Acidic Electrochemical Reduction of CO₂ Using Nickel Nitride on Multiwalled Carbon Nanotube as Selective Catalyst

Abstract

Ni3N/MCNT (multiwalled carbon nanotube) nanocomposites fabricated by ammonolysis displayed high CO2 electrochemical reduction reactivity with CO Faradaic efficiencies of 89.0% and current density of 6.5 mA cm–2 at −0.73 V vs reversible hydrogen electrode (RHE). The Ni3N/MCNT catalyst could operate under weakly acidic conditions in the pH range of 2.5–7.2. Even at pH 2.5, the CO Faradaic efficiency remained at 50.1%, demonstrating the high selectivity for CO2 reduction. The high catalyst selectivity could be due to increased adsorption of CO2 on the Ni3N surface, which can compete with hydrogen evolution under acidic conditions.

Cu2O/CuO Electrocatalyst for Electrochemical Reduction of Carbon Dioxide to Methanol

“…To perform the experiment in acidic medium, this study was mainly focused on just one intermediate pH value (here 5) to understand the catalytic behavior of all the electrocatalysts. Studies suggest that CO 2 can be reduced electrochemically to other hydrocarbons selectively in acidic electrolytes [37][38][39]. Subsequently, cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) tests were carried out.…”

Nanoengineering Metal–Organic Framework‐Based Materials for Use in Electrochemical CO2 Reduction Reactions

“…To date, diverse approaches have been employed to convert CO 2 into valuable chemicals, such as chemical transformation, electrocatalytic reduction, photocatalytic reduction, and biological conversion. [ 8 ] Notably, electrochemical CO 2 reduction reaction (CO 2 RR) is the most promising conversion pathway, owing to its unique advantages in the following aspects: 1) the possibility to conduct carbon dioxide reduction under mild conditions; [ 9 ] 2) the process has highly controllable reaction steps that allows adjusting electrochemical parameters with relatively high conversion efficiency; [ 10 ] 3) various renewable energy sources, such as wind energy, solar energy, water energy, and biomass energy, are used as a power source for electrocatalysis to store energy in synthetic chemicals; [ 11 ] 4) electrochemical reactors facilitate large‐scale industrial applications owing to their compactness and modularity.…”

Utilizing Metal-Organic Frameworks to Achieve High-Efficiency CO2 Electroreduction

“…Electrochemical processes are extremely important, and electrochemical devices are seen to be one of the most promising methods for reducing CO 2 by converting it into valuable fuels, including C 1 products (CO, HCOOH, CH 4 ), C 2 products (C 2 H 4 , C 2 H 6 , C 2 H 5 OH) and C 3 products (C 3 H 7 OH) [2]. This is mainly because CO 2 RR has highly adjustable steps to gain high conversion efficiency in moderate conditions [3]. Besides, electrochemical reactors are ideal for large-scale industrial applications with various renewable energy sources because of their compactness and adaptability [4].…”