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The magical combination of carbon and nitrogen: Why can this nanostructure exist stably in vacuum and liquid?
Nanomesh is an inorganic nanostructured two-dimensional material similar to graphene. This material was discovered in 2003 at the University of Zurich in Switzerland. It is mainly composed of boron (B) and nitrogen (N) atoms. It is formed by self-assembly at high temperature by exposing a clean platinum or rhodium surface to boron nitrogen compounds. Highly regular mesh structure. The nanonet shows the combination of hexagonal holes in great detail. At the nanoscale, the distance between the centers of each two holes is only 3.2 nanometers, while the diameter of each hole is about 2 nanometers and the depth is 0.05 nanometers. The bottom-most regions are tightly bonded to the underlying metal, while the top-most regions are connected to the surface only by strong cohesive forces within the layer.
"Not only is the nanomesh stable in vacuum, air, and certain liquids, it can also withstand temperatures as high as 796°C (1070K)."
What is special about this boron-nitrogen nanomesh is that it can capture molecules and metal clusters of similar size to the nanomesh holes and form an orderly arrangement. These properties make the material potentially useful in applications such as surface functionalization, spin electronics, quantum computing, and data storage media such as hard drives.
Structure
Hydrogen nitride (h-BN) nanomesh is a single layer of hexagonal boron nitride formed through a self-assembly process on a substrate such as rubidium (Rh(111)) or platinum (Ru(0001)) crystals. Its lattice constant is 3.2 nanometers, and the unit cell is composed of 13x13 BN or 12x12 Rh atoms, which means that in one unit cell, 13 boron or nitrogen atoms are located on 12 rubidium atoms. Due to the difference in the attractive force of certain chemical bonds, this causes fluctuations (corrugation) in the nanomesh, which in turn affects its electrical properties.
"Scanning tunnelling microscopy (STM) clearly distinguishes two different BN regions; a strongly bound region located within the pores and a weaker region located within the connected network." < /p>
Features
This nanonet shows stability in various environments, including air, water and electrolytes. Additionally, it is temperature resistant up to 1275K without decomposing. These remarkable stabilities enable the nanomesh to serve as a scaffold for metal nanoclusters and effectively capture molecules into regular arrangements. For example, when gold (Au) is evaporated onto the nanomesh, Au nanoparticles with distinct round shapes are formed, which are concentrated in the holes of the nanomesh.
"This means that the distances between molecules in these systems are wide and the intermolecular interactions are weak, which may be of interest in applications such as molecular electronics and memory devices."
Preparation and Analysis
The neat nanowebs were created by thermally decomposing HBNH, a colorless substance that is liquid at room temperature. The surface of Rh(111) or Ru(0001) is coated in a dust-free environment, and the boron nitride compounds are implanted by chemical vapor deposition (CVD) and maintained at 796°C (1070K) for reaction. Subsequently, its structure was observed using techniques such as scanning tunneling microscopy and low-energy electron diffraction.
Other forms and future prospects
CVD of boron nitride compounds on other substrates has not been successful in producing corrugated nanonetworks. On Ni and Pt, a flat BN layer was observed, whereas on Mo an exfoliated structure was observed. These findings highlight the uniqueness of the nanomesh structure and the chemical behavior during its formation.
When we think about the potential applications of this nanostructure, how might it affect materials science and various technological developments in the future?
