Porous heterostructure of graphene/hexagonal boron nitride as an efficient electrocatalyst for hydrogen peroxide generation
Mengmeng Fan, Zeming Wang, Yuying Zhao, Qixin Yuan, Jian Cui, Jithu Raj, Kang Sun, Ao Wang, Jingjie Wu, Hao Sun, Bei Li, Liang Wang, Jianchun Jiang
Abstract
Abstract Compared with the traditional heteroatom doping, employing heterostructure is a new modulating approach for carbon‐based electrocatalysts. Herein, a facile ball milling‐assisted route is proposed to synthesize porous carbon materials composed of abundant graphene/hexagonal boron nitride (G/h‐BN) heterostructures. Metal Ni powder and nanoscale h‐BN sheets are used as a catalytic substrate/hard template and “nucleation seed” for the formation of the heterostructure, respectively. As‐prepared G/h‐BN heterostructures exhibit enhanced electrocatalytic activity toward H 2 O 2 generation with 86%–95% selectivity at the range of 0.45–0.75 V versus reversible hydrogen electrode (RHE) and a positive onset potential of 0.79 versus RHE (defined at a ring current density of 0.3 mA cm −2 ) in the alkaline solution. In a flow cell, G/h‐BN heterostructured electrocatalyst has a H 2 O 2 production rate of up to 762 mmol g catalyst −1 h −1 and Faradaic efficiency of over 75% during 12 h testing, superior to the reported carbon‐based electrocatalysts. The density functional theory simulation suggests that the B atoms at the interface of the G/h‐BN heterostructure are the key active sites. This research provides a new route to activate carbon catalysts toward highly active and selective O 2 ‐to‐H 2 O 2 conversion.