LAUSR

Catalytic conversion of CO2 to valuable formate provides a pathway to carbon neutrality. Indium (In), as a promising catalyst, exhibits high selectivity toward formate due to its suitable bonding ability of *OCHO intermediates. However, it still suffers from the CO2 activation and the protonation steps, leading to low activity and productivity. Here, an oxygen‐pinned stabilization AgIn single‐atom alloy (Op‐Ag1In) is presented for efficiently converting CO2 into formate (≈92.03% Faradaic efficiency) with a partial current density of 13 mA cm−2 at −0.95 V vs RHE by using standard H‐type reactor. The Op‐Ag1In electrocatalyst is more effective in converting CO2 to formate because the activated In sites of Op‐Ag1In catalyst regulate CO2 activation and protonation step of CO2RR and formation of sufficient amounts of *OCHO, which are confirmed by in situ spectroscopic and theoretical calculations. The continuous production of formate is showcased at 70 mA cm–2 for 24 h by utilizing a flow cell and Op‐Ag1In.