scholarly journals The role of ligands in coinage-metal nanoparticles for electronics

2017 ◽  
Vol 8 ◽  
pp. 2625-2639 ◽  
Author(s):  
Ioannis Kanelidis ◽  
Tobias Kraus
Keyword(s):  
Metal Nanoparticles ◽  
Self Assembly ◽  
Colloidal Stability ◽  
Chemical Nature ◽  
Electronic Materials ◽  
Electronic Devices ◽  
Coinage Metal ◽  
Conductive Composites ◽  
Particle Shapes

Coinage-metal nanoparticles are key components of many printable electronic inks. They can be combined with polymers to form conductive composites and have been used as the basis of molecular electronic devices. This review summarizes the multidimensional role of surface ligands that cover their metal cores. Ligands not only passivate crystal facets and determine growth rates and shapes; they also affect size and colloidal stability. Particle shapes can be tuned via the ligand choice while ligand length, size, ω-functionalities, and chemical nature influence shelf-life and stability of nanoparticles in dispersions. When particles are deposited, ligands affect the electrical properties of the resulting film, the morphology of particle films, and the nature of the interfaces. The effects of the ligands on sintering, cross-linking, and self-assembly of particles in electronic materials are discussed.

scholarly journals Pyramidal Heteroanion-Directed and Reduced MoV-Driven Assembly of Multi-Layered Polyoxometalate Cages

2018 ◽  
Author(s):  
Qi Zheng, ◽  
Manuel Kupper ◽  
Weimin Xuan ◽  
Hirofumi Oki ◽  
Ryo Tsunashima ◽  
...  
Keyword(s):  
Self Assembly ◽  
Electronic Materials ◽  
Electronic Devices ◽  
Mixed Valence ◽  
The Self ◽  
Model Structure ◽  
Redox Titration ◽  
Metal Centers ◽  
Redox Active ◽  
Tetrabutyl Ammonium

The fabrication of redox-active polyoxometalates (POMs) that can switch between multiple states is critical for their application in electronic devices, yet, a sophisticated synthetic methodology is not well developed for such cluster types. Here we describe the heteroanion-directed and reduction-driven assembly of a series of multi-layered POM cages 1-10 templated by 1-3 redox-active pyramidal heteroanions. The heteroanions greatly affect the selfassembly of the resultant POM cages, leading to the generation of unprecedented three-layered peanut-shaped - 4, 7 and 8 - or bulletshaped - 5 and 6 - structures. The introduction of reduced molybdate is essential for the self-assembly of the compounds and results in mixed-metal (W/Mo), and mixed-valence (WVI/MoV) 1-10, as confirmed by redox titration, UV-Vis-NIR, NMR spectroscopy and mass spectrometry. 11, the tetrabutyl ammonium (TBA) salt derivative of the fully oxidized 3, is produced as a model structure for measurements to confirm that 1-10 are a statistical mixture of isostructural clusters with different ratios of W/Mo. Finally, multilayered POM cages exhibit dipole relaxations due to the presence of mixed valence WVI/MoV metal centers, demonstrating their potential uses for electronic materials.

scholarly journals Correlation-driven machine learning for accelerated reliability assessment of solder joints in electronics

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Vahid Samavatian ◽  
Mahmud Fotuhi-Firuzabad ◽  
Majid Samavatian ◽  
Payman Dehghanian ◽  
Frede Blaabjerg
Keyword(s):  
Machine Learning ◽  
Thermal Cycling ◽  
Solder Joints ◽  
Electronic Materials ◽  
Electronic Devices ◽  
Reliability Assessment ◽  
Electronic Systems ◽  
Learning Framework ◽  
Useful Lifetime

Abstract The quantity and variety of parameters involved in the failure evolutions in solder joints under a thermo-mechanical process directs the reliability assessment of electronic devices to be frustratingly slow and expensive. To tackle this challenge, we develop a novel machine learning framework for reliability assessment of solder joints in electronic systems; we propose a correlation-driven neural network model that predicts the useful lifetime based on the materials properties, device configuration, and thermal cycling variations. The results indicate a high accuracy of the prediction model in the shortest possible time. A case study will evaluate the role of solder material and the joint thickness on the reliability of electronic devices; we will illustrate that the thermal cycling variations strongly determine the type of damage evolution, i.e., the creep or fatigue, during the operation. We will also demonstrate how an optimal selection of the solder thickness balances the damage types and considerably improves the useful lifetime. The established framework will set the stage for further exploration of electronic materials processing and offer a potential roadmap for new developments of such materials.

scholarly journals The Role of Calix[n]arenes and Pillar[n]arenes in the Design of Silver Nanoparticles: Self-Assembly and Application

2020 ◽  
Vol 21 (4) ◽  
pp. 1425 ◽  
Author(s):  
Pavel Padnya ◽  
Vladimir Gorbachuk ◽  
Ivan Stoikov
Keyword(s):  
Gold Nanoparticles ◽  
Silver Nanoparticles ◽  
Metal Nanoparticles ◽  
Self Assembly ◽  
Silver Ions ◽  
Attractive Alternative ◽  
Controlled Synthesis ◽  
Plasmonic Sensors ◽  
Redox Stability

Silver nanoparticles (AgNPs) are an attractive alternative to plasmonic gold nanoparticles. The relative cheapness and redox stability determine the growing interest of researchers in obtaining selective plasmonic and electrochemical (bio)sensors based on silver nanoparticles. The controlled synthesis of metal nanoparticles of a defined morphology is a nontrivial task, important for such fields as biochemistry, catalysis, biosensors and microelectronics. Cyclophanes are well known for their great receptor properties and are of particular interest in the creation of metal nanoparticles due to a variety of cyclophane 3D structures and unique redox abilities. Silver ion-based supramolecular assemblies are attractive due to the possibility of reduction by “soft” reducing agents as well as being accessible precursors for silver nanoparticles of predefined morphology, which are promising for implementation in plasmonic sensors. For this purpose, the chemistry of cyclophanes offers a whole arsenal of approaches: exocyclic ion coordination, association, stabilization of the growth centers of metal nanoparticles, as well as in reduction of silver ions. Thus, this review presents the recent advances in the synthesis and stabilization of Ag (0) nanoparticles based on self-assembly of associates with Ag (I) ions with the participation of bulk platforms of cyclophanes (resorcin[4]arenes, (thia)calix[n]arenes, pillar[n]arenes).

scholarly journals Pyramidal Heteroanion-Directed and Reduced MoV-Driven Assembly of Multi-Layered Polyoxometalate Cages

2018 ◽  
Author(s):  
Qi Zheng, ◽  
Manuel Kupper ◽  
Weimin Xuan ◽  
Hirofumi Oki ◽  
Ryo Tsunashima ◽  
...  
Keyword(s):  
Self Assembly ◽  
Electronic Materials ◽  
Electronic Devices ◽  
Mixed Valence ◽  
The Self ◽  
Model Structure ◽  
Redox Titration ◽  
Metal Centers ◽  
Redox Active ◽  
Tetrabutyl Ammonium

The fabrication of redox-active polyoxometalates (POMs) that can switch between multiple states is critical for their application in electronic devices, yet, a sophisticated synthetic methodology is not well developed for such cluster types. Here we describe the heteroanion-directed and reduction-driven assembly of a series of multi-layered POM cages 1-10 templated by 1-3 redox-active pyramidal heteroanions. The heteroanions greatly affect the selfassembly of the resultant POM cages, leading to the generation of unprecedented three-layered peanut-shaped - 4, 7 and 8 - or bulletshaped - 5 and 6 - structures. The introduction of reduced molybdate is essential for the self-assembly of the compounds and results in mixed-metal (W/Mo), and mixed-valence (WVI/MoV) 1-10, as confirmed by redox titration, UV-Vis-NIR, NMR spectroscopy and mass spectrometry. 11, the tetrabutyl ammonium (TBA) salt derivative of the fully oxidized 3, is produced as a model structure for measurements to confirm that 1-10 are a statistical mixture of isostructural clusters with different ratios of W/Mo. Finally, multilayered POM cages exhibit dipole relaxations due to the presence of mixed valence WVI/MoV metal centers, demonstrating their potential uses for electronic materials.

Failure Analysis and Defect Inspection of Electronic Devices by High-Resolution Cathodoluminescence

2017 ◽  
Author(s):  
C. Monachon ◽  
M.S. Zielinski ◽  
D. Gachet ◽  
S. Sonderegger ◽  
S. Muckenhirn ◽  
...  
Keyword(s):  
Failure Analysis ◽  
Electronic Materials ◽  
Electronic Devices ◽  
Optical Emission ◽  
Large Field ◽  
Nanometer Scale ◽  
Defect Analysis ◽  
Defect Inspection ◽  
Spectrally Resolved ◽  
Non Destructive

Abstract Quantitative cathodoluminescence (CL) microscopy is a new optical spectroscopy technique that measures electron beam-induced optical emission over large field of view with a spatial resolution close to that of a scanning electron microscope (SEM). Correlation of surface morphology (SE contrast) with spectrally resolved and highly material composition sensitive CL emission opens a new pathway in non-destructive failure and defect analysis at the nanometer scale. Here we present application of a modern CL microscope in defect and homogeneity metrology, as well as failure analysis in semiconducting electronic materials

Directive Effect of Chain Length in Modulating Peptide Nano-assemblies

2020 ◽  
Vol 27 (9) ◽  
pp. 923-929
Author(s):  
Gaurav Pandey ◽  
Prem Prakash Das ◽  
Vibin Ramakrishnan
Keyword(s):  
Electron Microscopy ◽  
Amino Acids ◽  
Light Scattering ◽  
Chain Length ◽  
Self Assembly ◽  
The Self ◽  
Ionic Charge ◽  
Self Assembling ◽  
Biophysical Techniques

Background: RADA-4 (Ac-RADARADARADARADA-NH2) is the most extensively studied and marketed self-assembling peptide, forming hydrogel, used to create defined threedimensional microenvironments for cell culture applications. Objectives: In this work, we use various biophysical techniques to investigate the length dependency of RADA aggregation and assembly. Methods: We synthesized a series of RADA-N peptides, N ranging from 1 to 4, resulting in four peptides having 4, 8, 12, and 16 amino acids in their sequence. Through a combination of various biophysical methods including thioflavin T fluorescence assay, static right angle light scattering assay, Dynamic Light Scattering (DLS), electron microscopy, CD, and IR spectroscopy, we have examined the role of chain-length on the self-assembly of RADA peptide. Results: Our observations show that the aggregation of ionic, charge-complementary RADA motifcontaining peptides is length-dependent, with N less than 3 are not forming spontaneous selfassemblies. Conclusion: The six biophysical experiments discussed in this paper validate the significance of chain-length on the epitaxial growth of RADA peptide self-assembly.

Sticky ends in a self-assembling ABA triblock copolymer: the role of ureas in stimuli-responsive hydrogels

2019 ◽  
Vol 4 (1) ◽  
pp. 91-102 ◽  
Author(s):  
Ryan T. Shafranek ◽  
Joel D. Leger ◽  
Song Zhang ◽  
Munira Khalil ◽  
Xiaodan Gu ◽  
...  
Keyword(s):  
Self Assembly ◽  
Viscoelastic Properties ◽  
Triblock Copolymer ◽  
Thermal Response ◽  
Stimuli Responsive ◽  
Self Assembling ◽  
Polymeric Hydrogels ◽  
Aba Triblock Copolymer ◽  
Responsive Hydrogels

Directed self-assembly in polymeric hydrogels allows tunability of thermal response and viscoelastic properties.

scholarly journals Understanding the role of conjugation length on the self-assembly behaviour of oligophenyleneethynylenes

2021 ◽  
Author(s):  
Beatriz Matarranz ◽  
Goutam Ghosh ◽  
Ramesh Kandanelli ◽  
Angel Sampedro ◽  
Kalathil K. Kartha ◽  
...  
Keyword(s):  
Self Assembly ◽  
The Self ◽  
Conjugation Length ◽  
The Relationship

We unravel the relationship between conjugation length and self-assembly behaviour of oligophenyleneethynylenes (OPEs).

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