AI Article Synopsis
- - High-quality hexagonal BN (hBN) crystals are critical for new functional devices, but producing large-area continuous hBN films remains difficult, limiting their wider application in two-dimensional materials.
- - The study presents a new method using single-metal flux growth to create large, micron-thick hBN films, ensuring both high quality and the ability to transfer these films onto different substrates.
- - The produced hBN films show impressive properties, including narrow Raman line widths and extremely high thermal conductivity, indicating low defect density and making them suitable for various practical applications.
Article Abstract
High-quality hexagonal BN (hBN) crystals, owing to their irreplaceable roles in new functional devices such as universal substrates and excellent layered insulators are exceedingly required in the field of two-dimensional (2D) materials. Although large-scale monolayer hBN crystals have been successfully grown on catalytic metals, the synthesis of large-area continuous hBN films with thickness in microns is challenging, hindering their applications at the mesoscopic level. Herein, we report the single-metal flux growth of centimeter-large, micron-thick, and high-quality continuous hBN films by balancing the grain size and coverage. The as-grown films can be readily exfoliated and transferred onto arbitrary substrates. Isotopically engineered hBN crystals can be obtained as well by the method. The narrow Raman line widths of the intralayer E2g mode peak (2.9 cm-1 for h11BN, 3.3 cm-1 for h10BN, and 7.9 cm-1 for hNaBN) and ultrahigh thermal conductivity (830 W m-1 K-1 for 4L h11BN) demonstrate high crystal quality and low defect density. Our results provide the foundation for the cost-efficient and lab-achievable synthesis of high-quality hBN films aimed at its mesoscopic applications.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/d1nr02408f | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Polarisation-dependent Raman enhancement in hexagonal boron nitride membranes.
Nanoscale
December 2024
University of Warsaw, Faculty of Physics, Pasteura 5, 02-093 Warsaw, Poland.
Raman spectroscopy is a powerful analytical method widely used in many fields of science and applications. However, one of the inherent issues of this method is a low signal-to-noise ratio for ultrathin and two-dimensional (2D) materials. To overcome this problem, techniques like surface-enhanced Raman spectroscopy (SERS) that rely on nanometer scale metallic particles are commonly employed.
View Article and Find Full Text PDFNano-spherical tip-based smoothing with minimal damage for 2D van der Waals heterostructures.
Nanoscale
December 2024
ZJUI Institute, International Campus, Zhejiang University, Haining, 314400 China.
Two-dimensional materials and their heterostructures have significant potential for future developments in materials science and optoelectronics due to their unique properties. However, their fabrication and transfer process often introduce impurities and contaminants that degrade their intrinsic qualities. To address this issue, current atomic force microscopy (AFM) probe contact mode methods provide a solution by allowing cleaning and real-time observation of the nanoscale cleaning process.
View Article and Find Full Text PDFTunable hyperbolic polaritons with plasmonic phase-change material InSbTe.
Nanophotonics
March 2024
Wuhan National Laboratory for Optoelectronics and School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China.
Hyperbolic polaritons that originate from the extreme optical anisotropy in van der Waals (vdW) crystals have gained much attention for their potential in controlling nanolight. For practical use, there has been a strong interest to develop various manipulation strategies to customize the propagation of hyperbolic polaritons on a deeply sub-diffractional scale. In this regard, phase-change materials (PCMs) that possess two phases with different refractive indices offer suitably a tunable dielectric environment.
View Article and Find Full Text PDFGrowth of Noncentrosymmetric Two-Dimensional Single Crystals.
Precis Chem
July 2024
State Key Laboratory for Mesoscopic Physics, Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China.
Among the various two-dimensional (2D) materials, more than 99% of them are noncentrosymmetric. However, since the commonly used substrates are generally centrosymmetric, antiparallel islands are usually inevitable in the growth of noncentrosymmetric 2D materials because of the energetic equivalency of these two kinds of antiparallel islands on centrosymmetric substrates. Therefore, achieving the growth of noncentrosymmetric 2D single crystals has long been a great challenge compared with the centrosymmetric ones like graphene.
View Article and Find Full Text PDFSuper High- Unit-Cell-Thick α-CaCrO Crystals.
ACS Nano
November 2024
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, P. R. China.
High-dielectric-constant (high-) insulators are indispensable components to integrate semiconductors into metal-oxide-semiconductor field-effect transistors with sub-10 nm channel length, where the equivalent oxide thickness (EOT) of high- insulator needs to be decreased to subnanometer scale. The traditional insulators, including AlO, SiO, and HfO, fit well with the existing silicon industry but suffer from serious degeneration of insulating properties, such as large leakage currents caused by high-density borders and interface traps, when their thicknesses are reduced to a few nanometers. Here, we synthesize a high-quality nonlayered ultrathin α-CaCrO crystal down to unit-cell thickness (∼1.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!