Highly selective CO2 electrocatalytic reduction on nickel single-atom catalyst in a high-temperature shockwave method

Recently, the easily prepared catalysis used in CO2 electrochemical reduction with high selectivity and low cost has attracted more and more attention. Compared with the temperate wet chemical preparation method, which takes a long time and introduces some impurities, we found nickel metal catalysts can be easily and quickly synthesized on carbon black using the high-temperature shockwave method, which has the advantages of rapid heating up to 1300–1500 K within 0.5 s, no introduction of excess elements and extreme low unfavorable nitrogen dopants. Heating cycles and proportion of nitrogen source have been investigated on the catalyst morphology, particle size and electrocatalysis performance. Based on operando X-ray absorption and aberration-corrected scanning transmission electron microscopy (STEM) measurements, nickel single atom catalysts (Ni SACs) were prepared successfully and uniformly in modest heating cycles and proportion of nitrogen source. The Ni SACs exhibited remarkable performance in reducing carbon dioxide (CO2) to carbon monoxide (CO), with the current density of 27.5 mA/cm2 (−1.0 V vs reversible hydrogen electrode) and CO selectivity approaching 100 % in flow cell.