Shell-isolated gold nanoparticles (SHINs) were employed to record shell-isolated nanoparticle-enhanced Raman spectra (SHINERS) of a passive layer formed at surface during leaching from thiosulfate solutions. The (3-aminopropyl)triethoxysilane (APTES) and sodium silicate solution used coat with protective silica layer. This prevented interactions between the electrolyte core SHINs when SHINs-modified electrode was immersed into lixiviant. SHINERS layer, decomposition, contained bands...

Abstract The utility of supercapacitors for both fixed and portable energy storage would be greatly enhanced if their density could increased while maintaining high power density, fast charging time, low cost. This study describes a simple, solution‐phase, scalable modification carbon materials by covalently bonded “brush” hydrogen‐terminated graphene ribbons (GRs) with layer thicknesses 2–20 nm, resulting in 20–100 times increase the areal capacitance unmodified electrode surface. On flat...

Experimental measurements designed to test a specific model of the Pt‐Teflon bonded electrode are described. The assumes that catalyst agglomerates filled with electrolyte and Teflon binder creates hydrophobic channels, providing effective gas penetration. electrochemical surface area distribution adsorbed charge formed by reduction or oxidation were carried out for series electrodes different structure. Comparisons made BET pore volume distribution. results presented consistent proposed model.

Electrochemical deposition of aromatic organic molecules by reduction diazonium reagents enables formation molecular layers with sufficient integrity for use in electronic junctions interest to microelectronics. Characterization films thicknesses the 1-10 nm range is difficult Raman spectroscopy, since most structures have cross sections which are too small observe as either thin on solid electrodes or within intact junctions. Layer a 10 thick Ag island film flat carbon surface (eC/Ag)...

Abstract Eleven bilayer molecular junctions (MJs) consisting of two different 5–7 nm thick layers between conducting contacts are investigated to determine how orbital energies and optical absorbance spectra the oligomers affect photocurrent (PC) response, direction photoinduced charge transport, maximum response wavelength. Photometric sensitivity 2 mA W −1 a detection limit 11 pW demonstrated for MJs, yielding an internal quantum efficiency 0.14 electrons per absorbed photon. For unbiased...

Multiple layers in molecular junctions with different structures permit a wide range of electronic functions, including rectification, memory, and charge storage.

Preparation of a nanoparticle modified gold substrate designed for characterization hydrophilic self-assembled monolayers (SAMs) 1-thio-β-D-glucose (TG) with electrochemical surface-enhanced Raman spectroscopy (EC-SERS) is presented. Citrate stabilized nanoparticles were deposited on polycrystalline electrode and subjected to an desorption procedure completely remove all traces adsorbed citrate. Complete citrate was confirmed by recording cyclic voltammetry curves SERS spectra. The...

We provide compelling evidence that the cycling performance of 18650 Li-ion cells is adversely affected by excessive amounts electrolyte volume, with a noticeable decline observed within initial 30 cycles, particularly at higher discharge rates. This “high-volume effect” imposes additional constraints on optimization cell manufacturing, highlighting importance identifying its underlying causes. The electrochemical impedance 3.5 Ah cylindrical varying levels volume was extensively measured...

We present a detailed examination of Ni corrosion in lithium-ion battery Ni-coated steel cylindrical cell hardware, focusing on LiPF 6 -based electrolytes contaminated with water. The potential the hardware is predominantly controlled by iron component can which cathodically protects coating. Despite presence cathodic protection, coating still experiences significant crevice corrosion, as confirmed through chemical aging tests. Mechanistic investigations pure metal reveal two distinct...

An inexpensive, solution phase modification of flat carbon electrodes by electrochemical reactions a 1,8-diaminonaphthalene derivative results in 120- to 700-fold increase capacity formation 15–22 nm thick organic film. Modification high surface area with the same protocol resulted 12- 82-fold capacity. The layer contains 9–15% nitrogen present as −NH– redox centers that result large Faradaic component involving one H+ ion for each electron. showed no loss after prolonged cycling 0.1 M H2SO4...

Abstract Bilayer donor–acceptor molecular junctions are successfully fabricated with active layer thickness <15 nm to study the mechanism of photo‐induced charge transport. The bilayer devices exhibit lifetimes greater than 1 h laser irradiation, and a strong dependence sign magnitude photovoltage photocurrent on structure order layers. A distinct feature is covalent bonding between donor acceptor layers, which permits simultaneous absorption separation across heterojunction. In addition...

Development of a reproducible two-dimensional array gold nanoparticles (AuNPs) through guided assembly approach and sequentially using an electrochemical cleaning procedure to remove all capping ligands surface contaminants for studying gluconate, weak Raman scatterer, with surface-enhanced spectroscopy (SERS) is discussed. Here, unique use shell-isolated (NPs) presented by employing thin-cell configuration during NP deposition obtain highly monolayer AuNPs spacing 2× the SiO2 shell...

The properties of alkylthiol self-assembled monolayers (SAMs) on Au have been extensively characterized in the past few decades by exploiting a one-electron reductive desorption process. To date, oxidative thiol SAMs has relatively understudied because surface can be roughened during event. In this paper we describe alkylthiols with cyclic voltammetry and report effect pH, functional group chloride concentration peak potential for desorption. These potentials are compared visible observation...

An applied approach for in situ characterization of oxide ore samples exposed to a thiosulfate-based leaching solution with shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) is discussed. Differences passive layer growth during thiosulfate were observed the SHINERS spectra between untreated and pressure oxidation (POX)-treated received from Barrick Gold Corporation. The revealed that at ore–electrolyte interface contains metal sulfides significant quantities polysulfide...

Recent studies of the Au leaching process have employed thiosulfate as alternative complexing ligand to cyanide for gold extraction from ores containing carbonaceous components which preferentially absorbs and gold-cyanide complexes ( so called preg-robbing ). Thiosulfate, in presence an appropriate oxidant such dissolved oxygen, is well known complex Au(I) ions form a soluble [Au(S 2 O 3 ) ] 3- complex. However, kinetics this are inhibited by formation passivating layer species on surface...

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