Enhanced Crystallinity and Luminescence Characteristics of Hexagonal Boron Nitride Doped with Cerium Ions According to Tempering Temperatures

Hexagonal boron nitride was synthesized by pyrolysis using boric acid and melamine. At this time, to impart luminescence, rare earth cerium ions were added to synthesize hexagonal boron nitride nanophosphor particles exhibiting deep blue emission. To investigate the changes in crystallinity and luminescence according to the re-heating temperature, samples which had been subjected to pyrolysis at 900 °C were subjected to re-heating from 1100 °C to 1400 °C. Crystallinity and luminescence were enhanced according to changes in the reheating temperature. The synthesized cerium ion-doped hexagonal boron nitride nanoparticle phosphor was applied to the anti-counterfeiting field to prepare an ink that can only be identified under UV light.

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Blue emission at atomically sharp 1D heterojunctions between graphene and h-BN

Nature Communications ◽

10.1038/s41467-020-19181-2 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Gwangwoo Kim ◽

Kyung Yeol Ma ◽

Minsu Park ◽

Minsu Kim ◽

Jonghyuk Jeon ◽

...

Keyword(s):

Quantum Dots ◽

Boron Nitride ◽

Physical Properties ◽

Hexagonal Boron Nitride ◽

Graphene Quantum Dots ◽

Blue Emission ◽

Electronic States ◽

Optoelectronic Property ◽

Two Dimensional ◽

One Dimensional

Abstract Atomically sharp heterojunctions in lateral two-dimensional heterostructures can provide the narrowest one-dimensional functionalities driven by unusual interfacial electronic states. For instance, the highly controlled growth of patchworks of graphene and hexagonal boron nitride (h-BN) would be a potential platform to explore unknown electronic, thermal, spin or optoelectronic property. However, to date, the possible emergence of physical properties and functionalities monitored by the interfaces between metallic graphene and insulating h-BN remains largely unexplored. Here, we demonstrate a blue emitting atomic-resolved heterojunction between graphene and h-BN. Such emission is tentatively attributed to localized energy states formed at the disordered boundaries of h-BN and graphene. The weak blue emission at the heterojunctions in simple in-plane heterostructures of h-BN and graphene can be enhanced by increasing the density of the interface in graphene quantum dots array embedded in the h-BN monolayer. This work suggests that the narrowest, atomically resolved heterojunctions of in-plane two-dimensional heterostructures provides a future playground for optoelectronics.

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Cesium and bromine doping into hexagonal boron nitride

Journal of Materials Research ◽

10.1557/jmr.1986.0685 ◽

1986 ◽

Vol 1 (5) ◽

pp. 685-692 ◽

Cited By ~ 14

Author(s):

M. Sakamoto ◽

J.S. Speck ◽

M.S. Dresselhaus

Keyword(s):

Boron Nitride ◽

Hexagonal Boron Nitride ◽

Intercalation Compound ◽

Zone Method ◽

Paramagnetic Resonance ◽

Deep Blue ◽

Transmission Electron ◽

Host Materials ◽

Spin Resonance ◽

Electron Paramagnetic

Using a two-zone method, the possible formation of an intercalation compound of hexagonal boron nitride (BN) with Cs and Br2 was investigated. Only a few percent weight increase was observed by doping BN with Cs and Br2. The electron paramagnetic resonance (EPR) signal was significantly modified by Cs doping, which is attributed to the reaction between the Cs atoms and spin resonance centers (N vacancies) in BN; no change in the EPR spectra was observed with Br2 doping. However, the deep blue colored Cs-BN complex reported by Mugiya and co-workers was not obtained with the two-zone method. Though no evidence of systematic intercalation reaction in BN was observed in contrast to graphite host materials, intercalation islands induced by the introduction of Cs atoms were suggested by the transmission electron microscopy (TEM) observations.

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Insight into anomalous hydrogen adsorption on rare earth metal decorated on 2-dimensional hexagonal boron nitride: a density functional theory study

RSC Advances ◽

10.1039/d0ra01835j ◽

2020 ◽

Vol 10 (22) ◽

pp. 12929-12940

Author(s):

Shreeja Das ◽

Saroj K. Nayak ◽

Kisor K. Sahu

Keyword(s):

Rare Earth ◽

Boron Nitride ◽

Density Functional ◽

Hydrogen Adsorption ◽

Hexagonal Boron Nitride ◽

Earth Metal ◽

Functional Theory ◽

Hydrogen Molecules ◽

Strong Adsorption ◽

Insight Into

The central rare earth cerium atom and underlying apolar B–N bonds in two-dimensional hexagonal boron nitride facilitate a unique arrangement of hydrogen molecules which leads to fairly strong adsorption of eight hydrogen molecules per metal atom.

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NUCLEATE POOL BOILING AND CONDENSATION HEAT TRANSFER CHARACTERISTICS OF HEXAGONAL BORON NITRIDE/DICHLOROMETHANE NANOFLUID

Heat Transfer Research ◽

10.1615/heattransres.2020034308 ◽

2020 ◽

Vol 51 (11) ◽

pp. 1043-1059

Author(s):

Erdem Çiftçi ◽

Adnan Sözen

Keyword(s):

Heat Transfer ◽

Boron Nitride ◽

Hexagonal Boron Nitride ◽

Pool Boiling ◽

Condensation Heat Transfer ◽

Nucleate Pool Boiling ◽

Heat Transfer Characteristics ◽

Transfer Characteristics

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Marcus-Hush Theory Revealed by Electron Tunneling Through Hexagonal Boron Nitride

10.26434/chemrxiv.9275135.v1 ◽

2019 ◽

Author(s):

Matěj Velický ◽

Sheng Hu ◽

Colin R. Woods ◽

Peter S. Toth ◽

Viktor Zólyomi ◽

...

Keyword(s):

Electron Transfer ◽

Boron Nitride ◽

Electron Tunneling ◽

Hexagonal Boron Nitride ◽

Large Body ◽

Liquid Solution ◽

Limiting Current ◽

Electron Transfer Rate Constant ◽

Electrochemical Parameters ◽

Voltammetric Measurements

Marcus-Hush theory of electron transfer is one of the pillars of modern electrochemistry with a large body of supporting experimental evidence presented to date. However, some predictions, such as the electrochemical behavior at microdisk electrodes, remain unverified. Herein, we present a study of electron tunneling across a hexagonal boron nitride barrier between a graphite electrode and redox levels in a liquid solution. This was achieved by the fabrication of microdisk electrodes with a typical diameter of 5 µm. Analysis of voltammetric measurements, using two common redox mediators, yielded several electrochemical parameters, including the electron transfer rate constant, limiting current, and transfer coefficient. They show a significant departure from the Butler-Volmer behavior in a clear manifestation of the Marcus-Hush theory of electron transfer. In addition, our system provides a novel experimental platform, which could be applied to address a number of scientific problems such as identification of reaction mechanisms, surface modification, or long-range electron transfer.

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