Point defects in two-dimensional hexagonal boron nitride: A perspective

Zhang, Jijun; Sun, Rong; Ruan, Dongliang; Zhang, Min; Li, Yanxi; Zhang, Kai; Cheng, Faliang; Wang, Zhongchang; Wang, Zhiming

doi:10.1063/5.0021093

Cited by 51 publications

(56 citation statements)

References 197 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[16][17][18]20 Different types of point defects have been proposed as being the sources of the single photon emission observed in h-BN. 14,91,92 However, their morphological and electronic signatures have not been measured directly. Furthermore, a direct correlation with the optical emission is missing.…”

Section: Electronic Structure and Light Emission Related To Point Def...mentioning

confidence: 99%

Band gap measurements of monolayer h-BN and insights into carbon-related point defects

Román¹,

Costa²,

Zobelli³

et al. 2021

2D Mater.

View full text Add to dashboard Cite

Being a flexible wide band gap semiconductor, hexagonal boron nitride (h-BN) has great potential for technological applications like efficient deep ultraviolet (DUV) light sources, building block for two-dimensional heterostructures and room temperature single photon emitters in the UV and visible spectral range. To enable such applications, it is mandatory to reach a better understanding of the electronic and optical properties of h-BN and the impact of various structural defects. Despite the large efforts in the last years, aspects such as the electronic band gap value, the exciton binding energy and the effect of point defects remained elusive, particularly when considering a single monolayer.Here, we directly measured the density of states of a single monolayer of h-BN epitaxially grown on highly oriented pyrolytic graphite, by performing low temperature scanning tunneling microscopy (LT-STM) and spectroscopy (STS). The observed h-BN electronic band gap on defect-free regions is (6.8 ± 0.2) eV. Using optical spectroscopy to obtain the h-BN optical band gap, the exciton binding energy is determined as being of (0.7 ± 0.2) eV. In addition, the locally excited cathodoluminescence and photoluminescence show complex spectra that are typically associated to intragap states related to carbon defects. Moreover, in some regions of the monolayer h-BN we identify, using STM, point defects which have intragap electronic levels around 2.0 eV below the Fermi level.

show abstract

Section: Electronic Structure and Light Emission Related To Point Def...mentioning

confidence: 99%

Band gap measurements of monolayer h-BN and insights into carbon-related point defects

Román¹,

Costa²,

Zobelli³

et al. 2021

2D Mater.

View full text Add to dashboard Cite

show abstract

“…However, point defects such as vacancies are inevitable, which have been widely observed by aberration-corrected TEM imaging. 27,42,43 For hBN, it has been well-documented that triangular holes were initiated by vacancies, and they grew larger upon prolonged knock-on damages by electron radiation during TEM imaging. 44 Similarly, coherent triangular voids were formed between the aligned domains after a long time H 2 -induced vacancy etching.…”

Section: Resultsmentioning

confidence: 99%

Self-aligned stitching growth of centimeter-scale quasi-single-crystalline hexagonal boron nitride monolayers on liquid copper

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Figure 1 showed the model of a two-dimensional (2D) honeycomb SiC monolayer with point defects (e. g. C-vacancy and Sivacancy) and topological defect (e. g. Stone-Wales defects). Point defects were commonly observed in 2D materials, [15][16][17] which could drastically alter the electronic and chemical properties of 2D materials. For example, the electrocatalytic properties of ultrathin Co3O4 nanosheets exhibited improved oxygen evolution reaction after the introduction of O-vacancy.…”

Section: Resultsmentioning

confidence: 99%

SiC Monolayers as Promising Substrates for the Development of Highly Stable Palladium Single Atom Catalysts: A Density Functional Theory Study

Lim

Poh

2022

ChemPhysChem

View full text Add to dashboard Cite

Single-atom catalysts have been touted as highly efficient catalysts, but the catalytic single-atom sites are unstable and tend to aggregate into nanoparticles during chemical reactions. In this study, we show that SiC monolayers are promising substrates for the development of highly stable single-atom catalysts (Pd 1 /SiC) within the density functional theory. In presence of a Si-vacancy, the diffusion barrier energy of a Pd 1 atom embedded in the SiC monolayer is substantially enhanced from 2.3 to 7.8 eV, which is much higher than the reported diffusion barrier energies of graphene, boron nitride and defective MgO of the same catalytic system. Ab initio molecular dynamic calculations at 500 K also confirm the enhanced stability of Pd 1 /SiC monolayer (Si-vacancy) such that the Pd 1 atom remains embedded in the vacancy. Additionally, the Pd 1 / SiC monolayer (Si-vacancy) catalysts show a ~34 % reduction of activation barrier energy for CO oxidation as compared to pristine catalysts. This work implies that nanostructured SiC materials are promising substrates for the synthesis of highly stable single-atom catalysts.

show abstract

Point defects in two-dimensional hexagonal boron nitride: A perspective

Cited by 51 publications

References 197 publications

Band gap measurements of monolayer h-BN and insights into carbon-related point defects

Band gap measurements of monolayer h-BN and insights into carbon-related point defects

Self-aligned stitching growth of centimeter-scale quasi-single-crystalline hexagonal boron nitride monolayers on liquid copper

SiC Monolayers as Promising Substrates for the Development of Highly Stable Palladium Single Atom Catalysts: A Density Functional Theory Study

Contact Info

Product

Resources

About