Graphene–hBN non-van der Waals vertical heterostructures for four- electron oxygen reduction reaction

Abstract

A novel vertical non-van der Waals (non-vdW) heterostructure of graphene and hexagonal boron nitride (G/hBN) is realized and its application in direct four-electron oxygen reduction reaction (ORR) in alkaline medium is established.

Synthesis and Modification of Boron Nitride Nanomaterials for Electrochemical Energy Storage: From Theory to Application

“…Narayanan and co‐workers placed liquid exfoliated h‐BN into a CVD system and introduced a carbon source (CH 4 ) to achieve a novel thin G/h‐BN with a vertical non‐vdW heterostructure at a high temperature of 1000 °C (Figure 11f). [ 251 ] In contrast to the vdW‐type heterostructure, there were many chemical bridges (C–N and C–B chemical bonds) between graphene and h‐BN in this material, which allowed direct charge transfer, leading to more active positive charge sites for the ORR. In the saturated O 2 alkaline solution, the ORR peak of the G/h‐BN electrode was greatly enhanced (Figure 11g), and the ORR η showed a larger positive shift than that of pure h‐BN, suggesting that the composite electrode has an ORR catalytic activity and is a direct four‐electron pathway.…”

“…Graphene can improve the electronic structure of h-BN and transfer charges to the active sites of h-BN to enhance its ORR catalytic kinetics. [9,246,[249][250][251][252][253] For example, for a graphene-BN composite prepared by one-step hydrothermal and high-temperature annealing, the vdW effect between the graphite stacking and the BN sheet not only improved the uniformity of the composite but also made the effective distribution of charge on C and B atoms more conducive to oxygen adsorption and electroreduction. [249] Under alkaline conditions, the initial potential increased to 0.798 V (vs RHE), which is better than those of previously reported C-based ORR electrocatalysts.…”

“…i) ORR curves of Au and Pt electrode-modified BN. f-i) Reproduced with permission [251]. Copyright 2019, The Royal Society of Chemistry.…”

Boron vacancy: a strategy to boost the oxygen reduction reaction of hexagonal boron nitride nanosheet in hBN–MoS2 heterostructure

“…1(f)), the major peak is observed at 189.8 eV, along with a tiny shoulder peak at 192 eV corresponding to B-N bond and B-OH bond of hBN respectively. 10,24 Page 5 of 26 Nanoscale Advances…”

Electrochemically derived functionalized graphene for bulk production of hydrogen peroxide

“…Later, this method was modified by generating protons (H + ) through water oxidation which eliminated the direct purging of H 2 gas [9]. The major roadblock in this method is the development of a sustainable electrocatalyst for the selective reduction of oxygen to H 2 O 2 [19][20][21][22][23]. Today, most electrochemical H 2 O 2 production methods rely on precious-metal-based materials or transition metal and/or metal oxides, and hence their economic viability for the future technologies is highly questionable [10,[24][25][26][27].…”