Département de chimie moléculaire

N-rich C dots decorated graphene oxide (N-Cdots/GO) hybrid, as a metal-free electrocatalyst for O redn. reaction (ORR), is synthesized by a facile and low-cost hydrothermal treatment for the 1st time. Specifically, as a N-rich bridge-mol., urea can trap free citric acid on planar planes, edges, and wrinkle sections of GO through amidation reaction in the initial stage. Then, polymer-like intermediates are in situ formed and carbonized to N-Cdots on GO. Owing to the simultaneous N-doping into both Cdots and GO characterized by XPS, as well as the formation of defective graphitic structures analyzed by Raman spectra, the as-prepd. hybrid displays a remarkable electrocatalytic performance with more pos. onset potential (0.13 V vs. Ag/AgCl) and high kinetic c.d. (up to 18.4 mA cm-2 at -0.70 V) comparable to com. Pt/C catalyst. Also, it demonstrates significantly higher catalytic efficiency (nearly 100{%} of 4-electron ORR pathway) than those of N-Cdots or N-Cdots/GO mixt. with an outstanding cyclic stability and superior MeOH tolerance capability in alk. soln. [on SciFinder(R)]