In-plane graphene/boron-nitride heterostructures as an efficient metal-free electrocatalyst for the oxygen reduction reaction

Abstract

. (2016). In-plane graphene/boron-nitride heterostructures as an efficient metal-free electrocatalyst for the oxygen reduction reaction. Nanoscale, 8 (29), 14084-14091. In-plane graphene/boron-nitride heterostructures as an efficient metalfree electrocatalyst for the oxygen reduction reaction AbstractExploiting metal-free catalysts for the oxygen reduction reaction (ORR) and understanding their catalytic mechanisms are vital for the development of fuel cells (FCs). Our study has demonstrated that in-plane heterostructures of graphene and boron nitride (G/BN) can serve as an efficient metal-free catalyst for the ORR, in which the C-N interfaces of G/BN heterostructures act as reactive sites. The formation of water at the heterointerface is both energetically and kinetically favorable via a four-electron pathway. Moreover, the water formed can be easily released from the heterointerface, and the catalytically active sites can be regenerated for the next cycle. Since G/BN heterostructures with controlled domain sizes have been successfully synthesized in recent reports (e.g. Nat. Nanotechnol., 2013, 8, 119), our results highlight the great potential of such heterostructures as a promising metal-free catalyst for the ORR in FCs. Exploiting metal-free catalysts for the oxygen reduction reaction (ORR) and understanding their catalytic mechanisms are vital for the development of fuel cells (FCs). Our study has demonstrated that in-plane heterostructures of graphene and boron nitride (G/BN) can serve as an efficient metal-free catalyst for the ORR, in which the C-N interfaces of G/BN heterostructures act as reactive sites. The formation of water at the heterointerface is both energetically and kinetically favorable via a four-electron pathway. Moreover, the water formed can be easily released from the heterointerface, and the catalytically active site s can be regenerated for the next cycle. Since G/BN heterostructures with controlled domain sizes have been successfully synthesized in recent reports (e.g. Nat. Nanotechnol., 2013, 8, 119), our results highlight the great potential of such heterostructures as a promising metal-free catalyst for ORR in FCs.

Metal‐free graphene/boron nitride heterointerface for CO2 reduction: Surface curvature controls catalytic activity and selectivity

“…On the other hand, the CBM contributed from the π* C‐N orbitals along the C‐N interface, demonstrating the high conductivity and activity of C‐N interface. Based on this point, only C‐N interface is designed as the active site for the adsorption and reduction of CO 2 molecules, which is in good agreement with previous reports . To further identify the active site along the C‐N interface, the binding energies of *COOH on B site and N site have been tested as shown in Table S2.…”

“…G‐BN heterostructures can be regarded as the combination of zigzag graphene and zigzag BN, which have the similar crystal structures and lattice constants (only 1.8% mismatch) . After the combination of graphene and BN, G‐BN nanomaterials exhibit some unique characteristics, such as band gap opening, excellent thermal transport, and intrinsic half‐metallic behavior . For the G‐BN armchair nanotubes, previous works have proved that the smallest nanotube which can be constructed is G‐BN (3) .…”

“…As a typical two‐dimensional (2D) metal‐free material, pure graphene and BN have been wildly investigated due to their fascinating physical and chemical properties . However, since the free flowing of π electrons of sp 2 carbon materials and large band gap of BN, they are inert for many chemical reactions.…”

“…A series of N‐doped graphene materials have been realized in many electrocatalytic reactions, such as oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and CO 2 reduction reaction . These dopants and their doping methods play a significant role in catalyzing chemical reactions, compared to two disparate materials . Hybrid graphene‐BN (G‐BN) nanomaterials with armchair G‐BN interface, B‐C zigzag interface, and N‐C zigzag interface have been successfully synthesized in laboratory .…”

First‐Principles Study of Electrocatalytically Reversible CO2 Capture on Graphene‐like C3N

“…[46][47][48] The generalized gradient approximation (GGA) is used to sufficiently optimize all the configurations, [49] which is dealt by the Perdew-Burke-Ernzerhof (PBE) functional form together with long range dispersion correction approach with Grimme's scheme. [51][52][53] The constant of original optimized C 3 N monolayer is a = b = 4.862 Å , and a 3 3 supercell of C 3 N monolayer is applied to investigate the interaction between CO 2 /N 2 /CH 4 /H 2 and C 3 N monolayer. The calculation level has been used successfully for the investigations of the interactions and reaction mechanisms between gases and adsorbents.…”