Forming a B-B bond in boron carbon nitride composite: A way for metal free electrocatalyst for oxygen reduction reaction in alkaline medium

Unmanageable of oxygen electrochemistry on cathode side of fuel cells creates a major hindrance to designing a cell device. Effectively, Platinum alone cannot afford the oxygen reduction reaction (ORR) due to several worries such as unaffordable cost, stability, scarcity and intermediate tolerance etc. that would hurdle the development of fuel cell technology. In order to demonstrate similar efforts, we discuss a synthesis of boron carbon nitride (BCN) nanosheets and its composite by thermal and solvothermal method respectively. The BCN nanosheets also show the formation of a homonuclear B-B bond, which are important for enhancing oxygen affinity. Since the chemistry of B-B bond involves higher bond energy, more reactivity or unusual gas adsorption behavior, thus making such sites promising towards stronger electrophilic interactions such as oxygen adsorption followed by its reduction. As synthesized BCN exhibits an interesting onset potential of similar to 0.94 V in electroreduction of oxygen. More importantly, upon composite formation with carbon black, BCN shows further enhancement in the ORR kinetics with an onset potential of 1.01 V and a current density of 5 mA/cm(2), which is very much comparable with Pt/C. An interesting phenomenon of activating O-2 reduction using BCN has been systematically studied to unravel noble metal-free electrocatalysis. (C) 2019 Elsevier Inc. All rights reserved.