RSC Advances, 2014, Vol.4(35), pp.18286-18293
On the way to become promising oxygen reduction reaction (ORR) catalysts, the hybrids composed of reduced graphene oxide (RGO) and transition metal oxides are suffering from stacking of RGO sheets. In this work, a Co 3 O 4 /RGO/acetylene black (AB) hybrid was successfully synthesized via a facile one-step solution-phase route with sandwiching of AB particles between the RGO sheets during the synthesis of Co 3 O 4 /RGO, which can effectively tackle the stacking of RGO sheets. Compared with Co 3 O 4 /RGO, Co 3 O 4 /RGO/AB-P (mixing AB with the pre-prepared Co 3 O 4 /RGO with stirring), Co 3 O 4 /RGO/AB-M (mixing AB with Co 3 O 4 /RGO during the fabrication of the Co 3 O 4 /RGO catalytic layer for ORR) and commercial 10 wt% Pt/C, the Co 3 O 4 /RGO/AB hybrid exhibits increases of 50.6%, 32.5%, 37.9% and 8.9% in the ORR current density, respectively. This indicates that the introduction strategy of AB to Co 3 O 4 /RGO plays a vital role in the enhancement of ORR catalytic activity. Moreover, the Co 3 O 4 /RGO/AB hybrid shows a subtle ascending trend in the ORR current density during continuous operation for 72000 s, while Pt/C exhibits a 9.0% decrease. The exceptional ORR catalytic performance of Co 3 O 4 /RGO/AB can also be ascribed to the large specific surface area, well-anchored Co 3 O 4 nanoparticles on the RGO sheets, and low ohmic and kinetic impedances for ORR. We hope this work will be conducive for the extensive commercial applications of fuel cells.
Reduction ; Graphene ; Current Density ; Stacking ; Catalysts ; Synthesis ; Acetylene ; Catalysis ; Chemical and Electrochemical Properties (MD) ; Chemical and Electrochemical Properties (Ep) ; Chemical and Electrochemical Properties (Ed) ; Chemical and Electrochemical Properties (EC);