Search results for "Electrode"
showing 10 items of 950 documents
Gold nanoparticles/electrochemically expanded graphite composite: A bifunctional platform toward glucose sensing and SERS applications
2019
Abstract An integrated nanogold/expanded graphite based sensor was fabricated by a former electrochemical etching of the pencil lead electrode (PLE) and a later in-situ deposition of gold nanoparticles (AuNPs). The electrochemical pretreatment of PLE (EPLE) created a 3D graphene-like surface, enhanced the electrode surface area and facilitated the electron transfer ability within 5 min without any hazardous chemicals added. The obtained AuNPs/EPLE sensor had an excellent electrochemical response to glucose with a wide linear concentration range, from 0.05 to 38 mM and 38 to 60 mM, and a low detection limit of 5 μM (S/N = 3). Furthermore, the AuNPs/EPLE sensor was successfully employed to de…
Controlled solution-based fabrication of perovskite thin films directly on conductive substrate
2021
Abstract Organometallic perovskites are one of the most investigated materials for high-efficiency thin-film devices to convert solar energy and supply energy. In particular, methylammonium lead iodide has been used to realize thin-film perovskite solar cells, achieving an efficiency higher than 20%. Different fabrication procedures based on the spin-coating technique have been proposed, which do not ensure homogenous morphologies. In this work, we present a scalable process to fabricate methylammonium lead iodide thin films directly on conductive substrates, consisting of electrodeposition and two subsequent chemical conversions. A thorough investigation of the morphological, structural an…
Efficient Vacuum Deposited P-I-N Perovskite Solar Cells by Front Contact Optimization.
2020
Hole transport layers HTLs are of fundamental importance in perovskite solar cells PSCs , as they must ensure an efficient and selective hole extraction, and ohmic charge transfer to the corresponding electrodes. In p i n solar cells, the ITO HTL is usually not ohmic, and an additional interlayer such as MoO3 is usually placed in between the two materials by vacuum sublimation. In this work, we evaluated the properties of the MoO3 TaTm TaTm is the HTL N4,N4,N4 amp; 8243;,N4 amp; 8243; tetra [1,1 amp; 8242; biphenyl] 4 yl [1,1 amp; 8242; 4 amp; 8242;,1 amp; 8243; terphenyl] 4,4 amp; 8243; diamine hole extraction interface by selectively annealing either MoO3 prior to the deposition of TaTm o…
Formation of lead by reduction of electrodeposited PbO2: comparison between bulk films and nanowires fabrication
2012
Metallic lead was deposited, both in form of bulk films and nanowire array within pores of anodic alumina membranes, following a new two-step procedure, consisting in anodic electrodeposition of α-PbO2, followed by its reduction to metallic lead. This method allows to overcome drawbacks of the “direct” electrodeposition of lead from aqueous solution, consisting, essentially, in the formation of dendritic deposits. Here, we report the comparison between results obtained in the two cases and discuss the kinetic of oxide reduction both for films and nanowires. Deposit morphology and structure are also discussed. We have found that reduction of α-PbO2 films proceeds always at high speed and uni…
Fabrication and Photoelectrochemical Behavior of Ordered CIGS Nanowire Arrays for Application in Solar Cells
2010
In this work, we report some preliminary results concerning the fabrication of quaternary copper, indium, gallium, and selenium CIGS nanowires that were grown inside the channels of an anodic alumina membrane by one-step potentiostatic deposition at different applied potentials and room temperature. A tunable nanowire composition was achieved through a manipulation of the applied potential and electrolyte composition. X-ray diffraction analysis showed that nanowires, whose chemical composition was determined by energy-dispersive spectroscopy analysis, were amorphous. A composition of Cu0.203In0.153Ga0.131Se0.513, very close to the stoichiometric value, was obtained. These nanostructures wer…
Growth and characterization of horizontally suspended CNTs across TiN electrode gaps.
2010
A technique is proposed to grow horizontal carbon nanotubes (CNTs) bridging metal electrodes and to assess their electrical properties. A test structure was utilized that allows for selective electrochemical sidewall catalyst placement. The selectivity of the technique is based on the connection of the desired metal electrodes to the silicon substrate where the potential for electrochemical deposition was applied. Control over the Ni catalyst size (15-30 nm) and density (up to 3 x 10(11) particles cm(-2)) is demonstrated. Horizontal CNTs with controlled diameter and density were obtained by CVD growth perpendicular to the sidewalls of patterned TiN electrode structures. Electrode gaps with …
Comparison of spike parameters from optically identified GABAergic and glutamatergic neurons in sparse cortical cultures
2015
We are pleased to note that our publication “Comparison of spike parameters from optically identified GABAergic and glutamatergic neurons in sparse cortical cultures” by Weir et al. (2015) raised some discussion on the feasibility of solely electrophysiological discrimination of distinct neuronal subpopulations in vitro. We agree with Becchetti and Wanke (2015) that their report and our study on the same question were conducted with different technical approaches and that this may explain the observed differences between both studies. Although we obviously recorded a reduced spontaneous neuronal activity under our sparse culture conditions, these conditions were necessary to enable the uneq…
Cardiac arrhythmias induced by an electrical stimulation at a cellular level
2008
To provide insights into the impulse propagation between cardiac myocytes, we performed studies of excitation spread with cellular resolution in confluent monolayers of cultured cardiomyocytes (CM). Multisite field potentials have been recorded using microelectrode arrays (MEA) technology in a basal condition and in proarrhythmic conditions induced by a high frequency electrical stimulation. The in vitro observation of spiral waves opens a new way to test the anti-arrhythmic drugs or strategies at cellular level.
Fall of Potential Measurement of the Earth Resistance in Urban Environments: Accuracy Evaluation
2019
Both Standards EN 50522 and IEEE 81 propose the fall of potential method (FPM) to carry out the measurement of the resistance to earth ( $R_{\text{ES}}$ ) of an earthing system (ES). However, in urban areas, the recommended distances between the ES and auxiliary electrodes are not easy to respect, due to the presence of buildings and tarmac. Furthermore, unknown buried metallic parts and interconnections among ESs could modify the earth potential profile of the area, affecting the measurement results. In this paper, the key-issues that influence the measured $R_{\text{ES}}$ when the FPM is used in an urban environment are presented. A parametric analysis, carried out with Comsol Multiphysic…
Laparoscopic endopelvic sacral implantation of a Brindley controller for recovery of bladder function in a paralyzed patient
2008
Background: A number of techniques are being investigated to accomplish bladder control recovery in paralyzed patients using the neurostimulation, but currently, all techniques are based on the dorsal implantation of the electrodes using a laminectomy. Methods: On 27 April 2006 we performed a laparoscopic implantation of a Finetech-Brindley bladder controller on the endopelvic sacral roots in a Th8 completely paralyzed woman who had previously undergone the removal of a Brindley controller due to an arachnoiditis after extrathecal implantation with intradural sacral deafferentation. Results: We required about 3.5 h for the entire surgical procedure; no complications occurred and the patient…