The electrocatalytic reduction of CO₂ (CO₂RR) into value-added hydrocarbons is limited due to high limiting potential (U_L) and competing hydrogen evolution reaction (HER). To find the best catalyst for CO₂ reduction the concept of hydrogen poisoning was not considered in the catalyst screening process. Herein, we present a simple screening method and graphical construction using multiparameter optimization for the design of highly active and selective single-atom catalysts (SAC) using density functional theory calculations. A series of SAC namely, MN4, MBN3 and H@MBN3 (M: metal) are investigated for CO₂RR. Our results revealed that MN4 and MBN3 SAC are not favorable for CO₂RR due to high U_L > −0.85 V and hydrogen poisoning (ΔG_H* < 0), respectively. H@MBN3 SAC (stable compounds forming H–B bonds) are identified as efficient catalysts with a low value of U_L and significantly hinder the competitive HER. Among these, H@CoBN3 and H@FeBN3 SAC show excellent CO₂RR activity with limiting potential −0.30 and −0.44 V respectively for CH₄ production and no chance of HER. Scaling relations reveal the importance of *COOH/*CHO binding energy (E_b) as an energy descriptor to evaluate the catalytic performance. This work provides a new theoretical perspective to design a highly selective catalyst for CO₂RR.

_{由于高极限电位 (U L} ) 和竞争性析氢反应 (HER)，将 CO ₂ (CO ₂ RR)电催化还原成增值碳氢化合物受到限制。_{为了找到用于CO 2}还原的最佳催化剂，在催化剂筛选过程中没有考虑氢中毒的概念。在此，我们提出了一种使用多参数优化的简单筛选方法和图形构造，用于使用密度泛函理论计算设计高活性和选择性单原子催化剂 (SAC)。研究了一系列 SAC，即 MN4、MBN3 和 H@MBN3（M：金属）对 CO ₂ RR 的影响。我们的结果表明 MN4 和 MBN3 SAC 不利于 CO ₂RR 分别由于高 U _L  > −0.85 V 和氢中毒 (ΔG _H*  < 0)。H@MBN3 SAC（形成 H-B 键的稳定化合物）被认为是具有低 U _L值的高效催化剂，并且显着阻碍了竞争性 HER。其中，H@CoBN3 和 H@FeBN3 SAC 显示出优异的 CO ₂ RR 活性，对于 CH ₄生产的限制电位分别为 -0.30 和 -0.44 V，并且没有 HER 的机会。_{比例关系揭示了*COOH/*CHO 结合能 (E b} ) 作为评估催化性能的能量描述符的重要性。_{该工作为设计高选择性CO 2} RR催化剂提供了新的理论视角。