A rational design of electrocatalyst for oxygen reduction reaction (ORR) with activity 2–3 times higher than platinum has been of great demand for low temperature fuel cell applications. Particularly, metal-free ORR electrocatalysis has recently been explored rigorously because of limitations such as high price and scarcity of the state-of-the-art platinum catalyst. Here, we present a simple one-step method for the synthesis of carbon-doped hexagonal boron nitride (BNC) by a chemical vapor deposition method. An inert and insulating h-BN has been made active by carbon doping. From the structural analysis using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), we confirmed the formation of novel BNC nanostructures. BNC nanostructures exhibit rice grain-like shape having length ∼ 50 nm with interlayer distance of 0.34 nm, indicating hexagonal stacking of BN layers. As-synthesized BNC nanostructures obtained after annealing at 850 °C (BNC2-850) show interesting catalytic activity toward ORR with onset potential of 0.83 V versus RHE and a current density of 4.6 mA/cm2 in alkaline condition. More interestingly, the BNC2-850 nanostructures also reveal better stability even up to 10,000 potential cycles with concomitant negligible poisoning effect during methanol crossover process. Such a systematic and controlled study of carbon doping in h-BN nanostructures could certainly support the promising candidature of BNC as a metal-free electrocatalyst toward ORR.

Transition metals and metal oxides are carrying out vibrant role in electrooxidation of methanol. Unfortunately, the unclear cognition of methanol oxidation reaction (MOR) mechanism hampers the development of high performance electrocatalysts. Thus, in this report, a fascinating MOR mechanism has been studied using CoCuBi oxide foam structure, where the (220) plane of CoCuBi oxides are playing an exciting role in an unprecedented mechanism. Interestingly, the (220) plane belongs to the families of plane, where transition metal oxides prefer Eley‐Rideal (ER) mechanism with concomitant reduction in the poisoning effect due to CO. The synergetic effect of these planes triggers the excellent current density of 118 mA/cm2 with 50% retention of activity even after 10 h stability test. X‐ray photoelectron spectroscopy (XPS) and X‐ray diffraction (XRD) studies revealed different oxidation states of metal ions indicating formation of mixed oxides along with different phase formation in CoCuBi foam structure. More excitingly, CoCuBi nanocomposites show remarkable electrochemical methanol oxidation to form specific product such as formate, which is strongly confirmed by proton NMR spectroscopy.

Cobalt oxide with B,N,S tri-doped reduced graphite oxide exhibits synergistic effects to enhance ORR activity.

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