We propose here a facile electrodeposition method that is assisted by N,N-Dimethylformamide (DMF) selective coordination with Pt ions, and succeed in synthesizing highly active PtCo alloy catalysts for the oxygen reduction reaction (ORR). It is very ingenious that DMF is selectively coordinated with Pt ions, thus greatly bridging the deposition potential gap between Pt and Co, and promoting the formation of alloy catalysts. The optimal Pt4Co alloy sample exhibits a remarkable specific activity as high as 1.52 mA . cm(-2) Pt at 0.9 V (vs. RHE) towards the ORR, 7 times of that for the commercial Pt/C catalyst. It is believed that the remarkable ORR electrocatalytic activity is mainly ascribed to the synergetic effect from two aspects dealing with a DMF selective coordination with Pt ions as well as the generation of highly porous Pt-rich surfaces. (c) 2018 The Electrochemical Society.