A simple but efficient post-treatment strategy was developed to directly anchor highly active and dispersed copper sites on N/C for enhanced oxygen reduction reaction (ORR) electrocatalysis. The ORR activity and selectivity of the prepared CuÀN/C catalyst were significantly enhanced due to efficient binding of copper ions with nitrogen groups on the carbon skeleton to form highly active CuÀN sites. Moreover, the prepared CuÀN/C catalyst also exhibited excellent stability in alkaline electrolytes and Zn-air batteries, indicating great potential for energy applications.Developing cheap and efficient non-platinum group metal (non-PGM) electrocatalysts for oxygen reduction reaction (ORR) is highly desired for large-scale fabrication and application of next-generation ORR-involved sustainable energy devices, including fuel cell, metal-air battery, and chlor-alkali industry. [1,2] In the last decade, transition metal and nitrogen-co-doped nanocarbon (TMÀN/C) materials have been fabricated successfully and thus are promising candidates for replacing PGM materials toward efficient oxygen reduction electrocatalysis. [3][4][5][6] Doping nitrogen atoms into a carbon skeleton can change its intrinsic electronic structures, which then activates the inert conjugated p electrons to be active for ORR. [7,8] Furthermore, when transition metal and nitrogen atoms exist simultaneously during synthesis, highly active metal sites coordinated with nitrogen atoms (TM-N x ) on carbon matrix can be formed and thus significantly boost the ORR electrocatalytic performance of the derived catalyst through strong synergetic effects with nitrogen-doped sites. [9][10][11] However, conventional synthesis paths inevitably generate large-sized metal nanoparticles (NPs), making it difficult to distinguish the contributions from different types of metal sites as well as maximize the use of metal atoms.Recently, highly dispersed metal catalysts, especially singleatom catalysts (SACs) with singly dispersed and isolated metal sites on a support, has drawn much attention. [12,13] SACs not only can maximize the utilization of metal atoms, but also minimize the side reaction due to the homogeneity of metal active sites. Such unique catalysts with highly dispersed metal sites offer great potential for achieving high activity and selectivity, as well as identifying the active sites and revealing the catalytic mechanism for ORR on non-PGM materials. [14] Therefore, the controllable construction of TMÀN/C materials with highly dispersed TM-based sites on carbon matrix is a promising way to significantly improve their electrocatalytic properties for ORR. Y. Li et al. reported a metal-organic-framework (MOF)-based synthesis strategy for Co-based ORR SACs, in which Co-N 2 sites with a strong interaction with peroxide showed superior activity to Co-N 4 sites and Co NPs. [15] Furthermore, an MOF-based cage-encapsulated-precursor pyrolysis strategy was developed to fabricate Fe-based ORR SACs, the electrocatalytic performance of which outperformed commercial Pt/C a...