To address the sluggish kinetics of the electrochemical oxygen reduction reaction (ORR), we consider a family of silver-based dilute nanoalloys by alloying the Ag(1 1 1) with one 3d transition metal atom M (M = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn) as ORR catalysts in alkaline media. The M₁Ag(1 1 1) dilute nanoalloys exhibit higher stability when M is on the subsurface (2L-M₁Ag(1 1 1)) than when M is on the surface (1L-M₁Ag(1 1 1)) of the Ag(1 1 1) facet as observed from surface segregation and mixing energies, and this subsurface stability is attributed to the relative positive charge transfer of surface Ag atoms as revealed from atomic charge analysis. Thus, 2L-M₁Ag(1 1 1) catalysts are further investigated for their electronic structure and ORR activities. Particularly, 2L-Cu₁Ag(1 1 1), 2L-Ni₁Ag(1 1 1) and 2L-Zn₁Ag(1 1 1) dilute nanoalloys exhibit a free-atom-like d state, and 2L-Mn₁Ag(1 1 1) and 2L-Cu₁Ag(1 1 1) dilute nanoalloys exhibit an ORR overpotential of 0.459 and 0.468 V, respectively. For the first time, the ternary 2L-Cu₁Mn₁Ag(1 1 1) is theoretically predicted with an overpotential of 0.450 V. Motivated by this prediction, we prepare a ternary CuMnAg nanoalloy by using the pulse laser deposition method. These ternary CuMnAg and dealloyed DE-CuMnAg catalysts exhibit an ORR overpotential of 0.50 and 0.47 V that is close to the predicted overpotential and that of a commercial Pt/C catalyst.

为解决电化学氧还原反应（ORR）的反应迟钝动力学问题，我们考虑了一种通过将Ag（1 1 1）与一个3d过渡金属原子M（M = Sc，Ti，V， Cr，Mn，Fe，Co，Ni，Cu，Zn）作为碱性介质中的ORR催化剂。当M在表面（2L-M ₁ Ag（1 1 1））上时，M ₁ Ag（1 1 1）稀纳米合金比在表面（1L-M ₁ Ag（1 1 1））上表现出更高的稳定性从表面偏析和混合能观察到的Ag（1 1 1）晶面的表面电荷），这种表面下的稳定性归因于表面Ag原子的相对正电荷转移，这从原子电荷分析中可以看出。因此，2L-M ₁Ag（1 1 1）催化剂的电子结构和ORR活性得到了进一步研究。特别是2L-Cu ₁ Ag（1 1 1），2L-Ni ₁ Ag（1 1 1）和2L-Zn ₁ Ag（1 1 1）稀纳米合金表现出游离原子状的d态和2L-Mn ₁ Ag（1 1 1）和2L-Cu ₁ Ag（1 1 1）稀释纳米合金的ORR过电势分别为0.459 V和0.468V。三元2L-Cu ₁ Mn ₁首次理论上预测Ag（1 1 1）的过电势为0.450V。根据这种预测，我们使用脉冲激光沉积方法制备了三元CuMnAg纳米合金。这些三元CuMnAg和脱合金的DE-CuMnAg催化剂显示的ORR过电位为0.50和0.47 V，接近于预测的过电位和商用Pt / C催化剂的过电位。