The spatial arrangement of metal nanoparticle (NP) arrays in block copolymers has many potential applications in OFET-type memory devices. In this study, we adopted a trapping approach in which we used a monolayer thin film of polystyrene-block-poly(4-vinylpyridine) (PS56k-b-P4VP8k)-a highly asymmetric diblock copolymer having a spherical micelle morphology-to incorporate various amounts of one...

The membrane-associated Mg(2+)-activated and Ca(2+)-activated adenosine 5'-triphosphatase (EC 3.6.1.3; ATPase) activities of Escherichia coli were further characterized. The degree of inhibition of membrane-bound Mg(2+)-(Ca(2+))-ATPase by a series of anions (i.e., sodium salts of nitrate, iodide, chloride, and acetate) was found to correlate with the relative chaotropic, or solubilizing, effect...

Surface coating with an organic self-assembled monolayer (SAM) can enhance surface reactions or the absorption of specific gases and hence improve the response of a metal oxide (MOx) sensor toward particular target gases in the environment. In this study the effect of an adsorbed organic layer on the dynamic response of zinc oxide nanowire gas sensors was investigated. The effect of ZnO surface...

In order to obtain a better understanding of short-range (SR) and long-range (LR) nanoparticle (NP) interactions during the self-assembly of dodecanethiol-coated Au NPs in toluene via drop drying, we have investigated the dependence of the island density, scaled island-size distribution (ISD), and scaled capture-zone distribution (CZD) on coverage, deposition flux, and NP size. Our results indi...

A microcantilever, coated with a monolayer of redox-controllable, bistable [3]rotaxane molecules (artificial molecular muscles), undergoes reversible deflections when subjected to alternating oxidizing and reducing electrochemical potentials. The microcantilever devices were prepared by precoating one surface with a gold film and allowing the palindromic [3]rotaxane molecules to adsorb selectiv...

We have studied the formation of self-assembled monolayers (SAMs) of n-alkanethiols on platinum thin films using X-ray photoelectron spectroscopy (XPS), reflection-absorption infrared spectroscopy (RAIRS), spectroscopic ellipsometry (SE), and contact angle (CA) measurements. Specifically, SAMs of 1-hexanethiol, 1-dodecanethiol, and 1-octadecanethiol were grown on polycrystalline Pt films, and t...

Emulsions of oil and water stabilized by adsorbed solid particles are known as solid-stabilized emulsions (often referred to as Pickering emulsions). Using confocal microscopy and environmental transmission electron microscopy, we have studied the self-assembly of colloidal-sized polystyrene particles and alkanethiol-capped silver nanopaticles in Pickering emulsions. Colloidal samples of monodi...

Gold nanoparticles have attracted intense interest in materials and physical chemistry since the development of simple solution-phase methods for their synthesis and stabilization. The unique physical properties of gold nanoparticles have created a wide variety of potential applications including biological markers, DNA sensors, molecular recognition systems and nanoscale electronics. Encapsula...

A combined spectroscopic method utilizing surface-enhanced Raman scattering (SERS) and infrared reflection–absorption spectroscopy (IRRAS) has been employed to study the structural complexities of a model bilayer system. These two vibrational spectroscopic techniques offer complementary information, and when used in concert, present an extremely powerful tool for the structural elucidation of u...

A new class of nanometer-scale, low power, solidstate devices is being investigated for the detection of CW agents and other hazardous vapors. These nanoelectronic chemical vapor sensors, or “chemiresistors” are comprised of nanometer-sized gold particles (1.2-2.4nm) encapsulated by monomolecular layers of functionalized alkanethiols (R-SH) deposited as thin films on interdigitated microelectro...