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

Abstract

Searching environmentally friendly and low‐cost catalysts for CO2 reduction is critical for the development of sustainable energy and environmental technologies. In this work, we report a novel heterointerface between graphene and BN nanotubes or nanoribbons as efficient catalysts for CO2 reduction with high activity and selectivity. The active sites are found to be at the C‐N interfaces of graphene‐BN (G‐BN) and their excellent catalytic performance is derived from the surface curvature effect. The density functional theory (DFT) results reveal that the most energy favorable pathway for the formation of CH3OH is * + CO2 → *COOH → *CO → *OCH → *OCH2 → *OCH3 → *CH3OH → * + CH3OH. And the formation of CH4 is through * + CO2 → *COOH → *CO → *OCH → *OCH2 → *OCH3 → *O + CH4 → *OH + CH4 → *H2O + CH4 pathway. Moreover, the calculated results further demonstrate that for the smaller index of G‐BN nanotubes, such as G‐BN (3), the formation of CH3OH product is much easier than the *O intermediate and CH4 molecule due to the lower free energy change. However, for the higher indexed G‐BN nanotubes, after forming *OCH3 intermediate, the generation of *O and CH4 molecule is more feasible, particularly for G‐BN (9), and the calculated limiting potential is only −0.42 V, which is higher than the best Cu‐based materials, like −0.93 V on Cu(111), and −0.74 V on Cu (211). This metal free heterostructure is confirmed to facilitate CO2 conversion with high activity and selectivity, demonstrating a great potential as a new type of catalyst for CO2 reduction.

Growth and Etching of Centimeter-Scale Self-Assembly Graphene–h-BN Super-Ordered Arrays: Implications for Integrated Electronic Devices

“…Theoretical calculations have shown that the in-plane heterostructures of graphene and BN can serve as efficient metal-free catalysts for the ORR, in which the C–N interfaces of G/BN heterostructures act as reactive sites . G-BN nanomaterials can also be used for CO 2 reduction, in which the C–N interface is found to be the active sites for this process . Our preparation method leads to a heterostructure with an adjustable boundary density, which is expected to provide a large number of catalytic sites and enormous improvements in both oxygen reduction and CO 2 reduction efficiency.…”

“…As the most typical 2D planar heterostructure, graphene and hexagonal boron nitride (h-BN) planar heterostructures possess great potential in wide applications, such as optics and electronics. − Graphene and h-BN share very similar crystal lattice parameters, allowing for epitaxial growth of planar heterostructures. − In-plane heterostructures have the advantage of being able to control physical properties, including the changeable band gap of graphene, , ability of C–N interfaces to act as reactive sites, , and so on . Although a series of achievements have been made in the synthesis of graphene–h-BN planar heterostructures, as-produced graphene–h-BN planar heterostructures generally exhibit an irregular dispersion, , random distributions, and small sizes. , In addition, the presence of grain boundaries within heterostructures largely compromises the high electron mobility and results in poor device performance. , Thus, controllable growth of large-area planar 2D heterostructure arrays with a uniform spatial orientation is highly desired …”

“…10−12 Graphene and h-BN share very similar crystal lattice parameters, allowing for epitaxial growth of planar heterostructures. 13−15 In-plane heterostructures have the advantage of being able to control physical properties, including the changeable band gap of graphene, 16,17 ability of C−N interfaces to act as reactive sites, 18,19 and so on. 20 Although a series of achievements have been made in the synthesis of graphene−h-BN planar heterostructures, asproduced graphene−h-BN planar heterostructures generally exhibit an irregular dispersion, 21,22 random distributions, and small sizes.…”

Influence of Ag Metal Dispersion on the Catalyzed Reduction of CO2 into Chemical Fuels over Ag–ZrO2 Catalysts

“…It is worth mentioning that, during the calculation, we found it difficult to break the C–O bond of the O atom bound with the Zr atom on Ag 4 /(ZrO 2 ) 9 , and the reduction product is CH 3 OH in both COOH * and HCOO * paths. Previous studies ,, have shown that CH 3 O * is the key intermediate and the oxygen binding of the catalytic site serves as a descriptor to determine the selectivity of the catalyst for CH 4 and CH 3 OH. On the Ag 4 /(ZrO 2 ) 9 catalyst, the final product was only CH 3 OH.…”

Reaction mechanism and kinetics for carbon dioxide reduction on iron–nickel Bi-atom catalysts

“…9 To date, a variety of electrocatalysts have been developed for the CO 2 reduction reaction (CO 2 RR), including metals, [10][11][12][13] metal nanoparticles, [14][15][16] metal alloys, [17][18][19][20] two-dimensional (2D) materials, 21,22 and metal-free materials. 23,24 Their practical applications are usually restricted due to their poor stability and selectivity. The recently emerging single-atom catalysts (SACs) have received great attention as efficient CO 2 RR electrocatalysts.…”