In-situ TEM electrical and mechanical properties measurements of one-dimensional inorganic nanomaterials

The bulk mechanical properties of a material will primarily be determined by the integrity of the grain boundaries which depends on the local chemistry and the boundary structure. Changes in the composition of the boundary may affect the strength of the atomic bonds through a redistribution of the electrons; this effect has been predicted from theoretical calculations1 but not determined experimentally. The structure of the boundary will be determined by the mismatch between the adjoining grains and it will affect the mechanism by which strain is transferred through the boundary. From static observations of the interaction between matrix and grainboundary dislocations the following scenario has been constructed for the transfer process through random boundaries; The interaction between the incoming matrix dislocation and those in the grain boundary cause the emission of a dislocation from a grain-boundary dislocation source into the adjacent grain. To preserve the contiguity of the grain boundary a residual dislocation will be created within the grain boundary.

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Mechanical Properties of Bamboo-like Boron Nitride Nanotubes by In Situ TEM and MD Simulations: Strengthening Effect of Interlocked Joint Interfaces

ACS Nano ◽

10.1021/nn202283a ◽

2011 ◽

Vol 5 (9) ◽

pp. 7362-7368 ◽

Cited By ~ 51

Author(s):

Dai-Ming Tang ◽

Cui-Lan Ren ◽

Xianlong Wei ◽

Ming-Sheng Wang ◽

Chang Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Boron Nitride ◽

Md Simulations ◽

Boron Nitride Nanotubes ◽

In Situ Tem ◽

Strengthening Effect

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The potentials and challenges of electron microscopy in the study of atomic chains

The European Physical Journal Applied Physics ◽

10.1051/epjap/2017160318 ◽

2017 ◽

Vol 78 (2) ◽

pp. 20701

Author(s):

Florian Banhart ◽

Alessandro La Torre ◽

Ferdaous Ben Romdhane ◽

Ovidiu Cretu

Keyword(s):

Electron Microscopy ◽

Electrical Transport ◽

In Situ Tem ◽

Free Standing ◽

One Dimensional ◽

Resonant States ◽

In Situ Experiments ◽

Atomic Chains ◽

Substantial Progress

The article is a brief review on the potential of transmission electron microscopy (TEM) in the investigation of atom chains which are the paradigm of a strictly one-dimensional material. After the progress of TEM in the study of new two-dimensional materials, microscopy of free-standing one-dimensional structures is a new challenge with its inherent potentials and difficulties. In-situ experiments in the TEM allowed, for the first time, to generate isolated atomic chains consisting of metals, carbon or boron nitride. Besides having delivered a solid proof for the existence of atomic chains, in-situ TEM studies also enabled us to measure the electrical properties of these fundamental linear structures. While ballistic quantum conductivity is observed in chains of metal atoms, electrical transport in chains of sp1-hybridized carbon is limited by resonant states and reflections at the contacts. Although substantial progress has been made in recent TEM studies of atom chains, fundamental questions have to be answered, concerning the structural stability of the chains, bonding states at the contacts, and the suitability for applications in nanotechnology.

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Mechanical Properties of Molybdenum Disulfide and the Effect of Doping: An in Situ TEM Study

ACS Applied Materials & Interfaces ◽

10.1021/acsami.5b06055 ◽

2015 ◽

Vol 7 (37) ◽

pp. 20829-20834 ◽

Cited By ~ 30

Author(s):

Aleksander A. Tedstone ◽

David J. Lewis ◽

Rui Hao ◽

Shi-Min Mao ◽

Pascal Bellon ◽

...

Keyword(s):

Mechanical Properties ◽

Molybdenum Disulfide ◽

In Situ Tem ◽

Effect Of Doping

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Epitaxial Growth of Diamond-Shaped Au1/2Ag1/2CN Nanocrystals on Graphene

Materials ◽

10.3390/ma14247569 ◽

2021 ◽

Vol 14 (24) ◽

pp. 7569

Author(s):

Chunggeun Park ◽

Jimin Ham ◽

Yun Jung Heo ◽

Won Chul Lee

Keyword(s):

Electron Beam Irradiation ◽

2D Materials ◽

Experimental Investigations ◽

Pristine Graphene ◽

In Situ Tem ◽

Casting Method ◽

Synthesis Conditions ◽

Alloy Nanocrystals ◽

Inorganic Nanomaterials

Epitaxial synthesis of inorganic nanomaterials on pristine 2D materials is of interest in the development of nanostructured devices and nanocomposite materials, but is quite difficult because pristine surfaces of 2D materials are chemically inert. Previous studies found a few exceptions including AuCN, AgCN, CuCN, and Cu0.5Au0.5CN, which can be preferentially synthesized and epitaxially aligned onto various 2D materials. Here, we discover that Au1/2Ag1/2CN forms diamond-shaped nanocrystals epitaxially grown on pristine graphene surfaces. The nanocrystals synthesized by a simple drop-casting method are crystallographically aligned to lattice structures of the underlying graphene. Our experimental investigations on 3D structures and the synthesis conditions of the nanocrystals imply that the rhombic 2D geometries originate from different growth rates depending on orientations along and perpendicular to 1D molecular chains of Au1/2Ag1/2CN. We also perform in situ TEM observations showing that Au1/2Ag1/2CN nanocrystals are decomposed to Au and Ag alloy nanocrystals under electron beam irradiation. Our experimental results provide an additional example of 1D cyanide chain families that form ordered nanocrystals epitaxially aligned on 2D materials, and reveal basic physical characteristics of this rarely investigated nanomaterial.

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