Highly selective conversion of CO2 to formate on SnOx/GDY heterostructured electrocatalyst

An important step in the efficient production of formate (HCOO-) from CO2 and water is the development of electrocatalysts with high selectivity, activity at large current densities. Here we report a new heterostructure electrocatalyst which demonstrate highly selective CO2 reduction reaction by selective growth of polycrystalline Tin oxides on the graphdiyne. Our results show the natural advantages of GDY in effectively regulating the valence states of Sn and phase structure transition of the catalyst, and increasing charge transfer capacity and number of active sites, resulting in excellent catalytic performance. The electrocatalyst can selectively and efficiently produce and stabilize the key *OCHO intermediates and promote the formation of formate by completely inhibiting the competing HER, greatly promoting CO2RR. The electrocatalyst shows superior CO2-to-formate conversion performance at ambient temperatures and pressures with a highest reaction selectivity of 99.5% and a high formate yield rate of 323.42 μmol h−1 cm−2 in a large current density of 112 mA cm−2 at a low applied potential of − 0.9 V versus RHE.