Conversion of carbon dioxide (CO₂) with the help of an appropriate electrocatalyst with high stability, low onset potential and exceptional selectivity is still one of the great tasks in the electrocatalytic reduction of CO₂ to valuable chemicals. Herein, by means of systematic first principles simulations, we investigate the CO₂ reduction reaction (CO₂RR) activity of zirconium based single, double, and triple atom (Zr_n@C₂N; n=1-3) catalysts anchored on the graphitic carbon-nitride monolayer. In tune with Sabatier principle, our results reveal that a moderate CO₂ binding is vital for a low onset potential for CO₂RR. Consequently, based on rigorous free energy calculations, the Zr-based single atom catalyst is found to be most effective to convert CO₂ to valuable products such as HCOOH and CH₃OH. It is worth noting that CO₂ reduction to HCOOH is spontaneous via *HCOO intermediate on Zr₁@C₂N and involves low onset potential of −0.23 V with respect to reversible hydrogen electrode (RHE) from the *COOH intermediate. Among all the catalysts evaluated computationally, the Zr SAC further reveals the lowest onset potential of −0.89 V for CH₃OH formation. The results show that the Zr-based catalysts especially the Zr₁@C₂N is found to effectively suppress the competitive hydrogen evolution reaction and promote the CO₂RR. Moreover, all the three catalysts exhibit high kinetic and thermal stability with negligible distortion due to which their structures can be retained very well up to 600 K. Thus, the current work may provide effective catalyst-design strategies for enhancing the electrocatalytic CO₂RR performance of Zr-based materials.

Ms Afshana Hassan

PhD Scholar, Islamic University of Science and Technology, Pulwama, J&K, India

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