To acquire the synergy effects between Sn and Cu for the jointly high Faradaic efficiency and current density, we develop a novel strategy to design the Sn-Cu alloy catalyst via a decorated co-electrodeposition method for CO₂ electroreduction to formate. The Sn-Cu alloy shows high formate Faradaic efficiency of 82.3% ± 2.1% and total C₁ products Faradaic efficiency of 90.0% ± 2.7% at −1.14 V vs. reversible hydrogen electrode (RHE). The current density and mass activity of formate reach as high as (79.0 ± 0.4) mA cm⁻² and (1490.6 ± 7.5) mA mg⁻¹ at −1.14 V vs. RHE. Theoretical calculations suggest that Sn-Cu alloy can obtain high Faradaic efficiency for CO₂ electroreduction by suppressing the competitive hydrogen evolution reaction and that the formate formation follows the path of CO₂ → HCOO* → HCOOH. The stepped (2 1 1) surface of Sn-Cu alloy is beneficial towards selective formate production.

为了获得 Sn 和 Cu 之间的协同效应以实现共同的高法拉第效率和电流密度，我们开发了一种新策略，通过用于 CO ₂电还原生成甲酸盐的装饰共电沉积方法设计 Sn-Cu 合金催化剂。与可逆氢电极 (RHE) 相比，Sn-Cu 合金在 -1.14 V 时显示出 82.3% ± 2.1% 的高甲酸盐法拉第效率和 90.0% ± 2.7% 的总 C ₁产物法拉第效率。甲酸盐的电流密度和质量活度在 -1.14 V 相对于 RHE 时高达 (79.0 ± 0.4) mA cm ^-2和 (1490.6 ± 7.5) mA mg ^{-1 。}_{理论计算表明，Sn-Cu合金对CO 2}可以获得较高的法拉第效率通过抑制竞争性析氢反应进行电还原，甲酸盐的形成遵循 CO ₂  → HCOO* → HCOOH 的路径。Sn-Cu合金的阶梯状（2 1 1）表面有利于选择性甲酸盐的产生。