The study on the reaction of gas-phase crxn- (x=2-7) anion clusters with co2

Efficient reduction of CO2 to CO under room temperature is of great importance for CO2 utilization. For the first time, the CO2 reduction by multinuclear transition-mental nitride cluster anions CrxN^-(x=2-7) under thermalcollision conditions has been identified by applying mass spectrometry in conjunction with density functional theory (DFT) calculations. The CrxN^-(x=2-7) and Cr2NH- clusters can react with CO2 to generate CrxNO- and CO, and the intermediate ternary anions CrxNO- can further reduce another CO2 to form CrxNO2 - and one CO molecules. All of these consecutive reactions are with high reactivity, and no CO2 adsorbate is formed. As the cluster size increases from Cr2N^-to Cr7N^-, the cluster reactivity first increases and then decreases slightly. The DFT calculations predict the structures of these reactive anions and reaction mechanisms for the consecutive reactions. This work shades new light into the design of active sites on reverse water gas shift catalysts.