We report the synergistic adsorption and activation of CO₂ by using magnesium oxide anchored into a hollow carbon sphere (MgO/HCS) as an efficient catalyst for electrochemical reduction of CO₂ (ERC). The MgO/HCS catalyst exhibits a high selectivity for CO production with a faradaic efficiency of 81.7% at −1.0 V VS. RHE and a partial current density (PCD) of 16.7 mA cm⁻² in aqueous electrolyte.