催化作用
氧还原反应
材料科学
热解
可逆氢电极
化学工程
碳纤维
解吸
工作(物理)
氢
电极
氧还原
电池(电)
氧气
功率密度
燃料电池
密度泛函理论
金属
Atom(片上系统)
碳纳米管
无机化学
多相催化
X射线光电子能谱
电催化剂
电流密度
过渡金属
纳米技术
作者
Hanjun Zhang,Jing Chen,Yuxin Shi,Yaoyue Yang,Xiaole Jiang
标识
DOI:10.1016/j.apsusc.2025.165205
摘要
• Cu–N–C single atom catalysts with adjustable carbon defects are fabricated. • Optimized Cu–N–C V -1000 shows superior ORR performance, outperforming Pt/C. • Cu–N–C V -1000-based ZAB has high peak power density and specific capacity. • High activity comes from synergistic effect between Cu–N x sites and carbon defects. • This work offers insights for designing efficient catalysts by defect engineering. Regulating the local microenvironment of metal centers represents an effective yet challenging approach to enhance the catalytic performance of atomically dispersed transition metal-nitrogen-carbon (M–N–C) catalysts towards the oxygen reduction reaction (ORR). Herein, atomically dispersed Cu–N–C catalysts featuring with adjustable carbon vacancies/defects concentrations (Cu–N–C V –X) are fabricated using a simple molten-salt-assisted pyrolysis strategy. The optimized catalyst (Cu–N–C V -1000) exhibits superior ORR catalytic performance with a half-wave potential ( E 1/2 ) of 0.89 V versus the reversible hydrogen electrode (RHE) and a turnover frequency ( TOF ) of 5.01 e site -1 s −1 at 0.85 V, surpassing Pt/C and most recently reported single-atom catalysts. Theoretical calculations confirm that defects adjacent to Cu–N 3 site downshift the d-band center of active sites, facilitating the desorption of *OH intermediate and thereby significantly enhancing the ORR kinetics. Consequently, the Cu–N–C V -1000-based zinc-air battery (ZAB) delivers a peak power density of 175.0 mW cm −2 along with a high discharge specific capacity of 819.4 mA g -1 Zn . This work confirms that the deliberate creation of suitable defects is an effective approach to optimize the intrinsic ORR activity of atomic M–N x sites, providing new insights into the rational design of high-performance catalysts for practical metal-air batteries.
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