Review and outlook: from single nanoparticles to self-assembled monolayers and granular GMR sensors

This paper highlights recent advances in synthesis, self-assembly and sensing applications of monodisperse magnetic Co and Co-alloyed nanoparticles. A brief introduction to solution phase synthesis techniques as well as the magnetic properties and aspects of the self-assembly process of nanoparticles will be given with the emphasis placed on selected applications, before recent developments of particles in sensor devices are outlined. Here, the paper focuses on the fabrication of granular magnetoresistive sensors by the employment of particles themselves as sensing layers. The role of interparticle interactions is discussed.

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Self-assembly of octadecyltrichlorosilane: Surface structures formed using different protocols of particle lithography

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.3.12 ◽

2012 ◽

Vol 3 ◽

pp. 114-122 ◽

Cited By ~ 30

Author(s):

ChaMarra K Saner ◽

Kathie L Lusker ◽

Zorabel M LeJeune ◽

Wilson K Serem ◽

Jayne C Garno

Keyword(s):

Self Assembly ◽

Self Assembled Monolayers ◽

Contact Printing ◽

Force Microscopy ◽

Atomic Force ◽

Assembly Mechanism ◽

Assembled Monolayers ◽

Particle Lithography ◽

Thickness Measurements

Particle lithography offers generic capabilities for the high-throughput fabrication of nanopatterns from organosilane self-assembled monolayers, which offers the opportunity to study surface-based chemical reactions at the molecular level. Nanopatterns of octadecyltrichlorosilane (OTS) were prepared on surfaces of Si(111) using designed protocols of particle lithography combined with either vapor deposition, immersion, or contact printing. Changing the physical approaches for applying molecules to masked surfaces produced OTS nanostructures with different shapes and heights. Ring nanostructures, nanodots and uncovered pores of OTS were prepared using three protocols, with OTS surface coverage ranging from 10% to 85%. Thickness measurements from AFM cursor profiles were used to evaluate the orientation and density of the OTS nanostructures. Differences in the thickness and morphology of the OTS nanostructures are disclosed based on atomic force microscopy (AFM) images. Images of OTS nanostructures prepared on Si(111) that were generated by the different approaches provide insight into the self-assembly mechanism of OTS, and particularly into the role of water and solvents in hydrolysis and silanation.

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Stochastic Computing via In Operando Modulation of Rectification in Molecular Tunneling Junctions

10.26434/chemrxiv.12839714.v1 ◽

2020 ◽

Author(s):

Xinkai Qiu ◽

Sylvia Rousseva ◽

Gang Ye ◽

Jan C. Hummelen ◽

Ryan Chiechi

Keyword(s):

Self Assembly ◽

Variable Temperature ◽

Self Assembled Monolayers ◽

Microfluidic Channels ◽

Proof Of Concept ◽

Glycol Ethers ◽

Stochastic Computing ◽

Assembled Monolayers ◽

In Operando ◽

Tunneling Junctions

This paper describes the reconfiguration of molecular tunneling junctions during operation via the self-assembly of bilayers of glycol ethers. We use well-established functional groups to modulate the magnitude and direction of rectification in assembled tunneling junctions by exposing them to solutions containing different glycol ethers. Variable-temperature measurements establish that rectification occurs by a bias-dependent tunneling-hopping mechanism and that glycol ethers, beside being an unusually efficient tunneling medium, behave identically to alkanes. We fabricated memory bits from crossbar junctions prepared by injecting eutectic Ga-In into microfluidic channels. Two 8-bit registers were able to perform logical AND operations on bit strings encoded into chemical packets as microfluidic droplets that alter the composition of the crossbar junctions through self-assembly to effect memristor-like properties. This proof of concept work demonstrates the potential for fieldable molecular-electronic devices based on tunneling junctions of self-assembled monolayers and bilayers.

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Mechanical and Charge Transport Properties of Alkanethiol Self-Assembled Monolayers on a Au(111) Surface: The Role of Molecular Tilt

Langmuir ◽

10.1021/la703147q ◽

2008 ◽

Vol 24 (5) ◽

pp. 2219-2223 ◽

Cited By ~ 45

Author(s):

Yabing Qi ◽

Imma Ratera ◽

Jeong Y. Park ◽

Paul D. Ashby ◽

Su Ying Quek ◽

...

Keyword(s):

Charge Transport ◽

Transport Properties ◽

Self Assembled Monolayers ◽

Assembled Monolayers ◽

Self Assembled

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The role of the terminal functional group of self-assembled monolayers on fiber matrix adhesion

Journal of Applied Polymer Science ◽

10.1002/app.24388 ◽

2007 ◽

Vol 106 (1) ◽

pp. 462-469 ◽

Cited By ~ 6

Author(s):

E. Feresenbet ◽

D. Raghavan ◽

G. A. Holmes

Keyword(s):

Functional Group ◽

Self Assembled Monolayers ◽

Matrix Adhesion ◽

Assembled Monolayers ◽

Fiber Matrix ◽

Self Assembled ◽

Terminal Functional Group

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Self-Assembled Monolayers on Nanostructured Composites for Electrochemical Sensing Applications

Handbook of Nanoelectrochemistry ◽

10.1007/978-3-319-15266-0_38 ◽

2015 ◽

pp. 417-478 ◽

Cited By ~ 1

Author(s):

Nada F. Atta ◽

Ekram H. El-Ads ◽

Ahmed Galal

Keyword(s):

Electrochemical Sensing ◽

Self Assembled Monolayers ◽

Nanostructured Composites ◽

Sensing Applications ◽

Assembled Monolayers ◽

Self Assembled

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Self-Assembled Monolayers on Nano-structured Composites for Electrochemical Sensing Applications

Handbook of Nanoelectrochemistry ◽

10.1007/978-3-319-15207-3_38-1 ◽

2015 ◽

pp. 1-51

Author(s):

Nada F. Atta ◽

Ekram H. El-Ads ◽

Ahmed Galal

Keyword(s):

Electrochemical Sensing ◽

Self Assembled Monolayers ◽

Sensing Applications ◽

Assembled Monolayers ◽

Self Assembled

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Self-assembly of biomolecules at surfaces characterized by NEXAFS

Canadian Journal of Chemistry ◽

10.1139/v07-079 ◽

2007 ◽

Vol 85 (10) ◽

pp. 793-800 ◽

Cited By ~ 10

Author(s):

Xiaosong Liu ◽

Fan Zheng ◽

A Jürgensen ◽

V Perez-Dieste ◽

D Y Petrovykh ◽

...

Keyword(s):

Surface Science ◽

Self Assembly ◽

Ribonuclease A ◽

Polarization Dependence ◽

Biological Molecules ◽

Self Assembled Monolayers ◽

Peptide Bonds ◽

Molecular Adsorbates ◽

Dna Oligonucleotides ◽

Assembled Monolayers

Surface science has made great strides towards tailoring surface properties via self-assembly of nanoscale molecular adsorbates. It is now possible to functionalize surfaces with complex biomolecules such as DNA and proteins. This brief overview shows how NEXAFS (near edge X-ray absorption fine structure spectroscopy) can be used to characterize the assembly of biological molecules at surfaces in atom- and orbital-specific fashion. To illustrate the range of applications, we begin with simple self-assembled monolayers (SAMs), proceed to SAMs with customized terminal groups, and finish with DNA oligonucleotides and Ribonuclease A, a small protein containing 124 amino acids. The N 1s absorption edge is particularly useful for characterizing DNA and proteins because it selectively interrogates the π* orbitals in nucleobases and the peptide bonds in proteins. Information about the orientation of molecular orbitals is obtained from the polarization dependence. Quantitative NEXAFS models explain the polarization dependence in terms of molecular orientation and structure.Key words: NEXAFS, bio-interfaces, ribonuclease A, immobilization, orientation.

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