Cyanogel auto-reduction induced synthesis of PdCo nanocubes on carbon nanobowls: a highly active electrocatalyst for ethanol electrooxidation.

Direct ethanol fuel cells (DEFCs) with a high conversion efficiency are quite promising candidates for energy conversion devices. Herein, we have successfully synthesized PdCo alloy nanocubes supported on carbon nanobowl (denoted as Pd2Co1/CNB) nanohybrids by using the cyanogel auto-reduction method at high temperature. The morphology, composition and structure of Pd2Co1/CNB nanohybrids are characterized in detail, revealing that PdCo nanocubes have a high alloying degree and special {110} facets. In cyclic voltammetry measurements, Pd2Co1/CNB nanohybrids show a mass activity of 1089.0 A g Pd-1 and a specific activity of 40.03 mA cm-2 for ethanol electrooxidation at peak potential, which are much higher than that of the commercial Pd/C electrocatalyst (278.2 A gPd-1 and 8.22 mA cm-2). Additionally, chronoamperometry measurements show that Pd2Co1/CNB nanohybrids have excellent durability for ethanol electrooxidation. A high alloying degree, special {110} facets and the CNB supporting material contribute to the high activity and durability of Pd2Co1/CNB nanohybrids, making them a highly promising Pt-alternative electrocatalyst for ethanol electrooxidation in DEFCs.