0000000001192150
AUTHOR
Germano Ferrara
Nanostructures of Lanthanide Oxy/Hydroxides Obtained by Metal Displacement Deposition
PVA-based acidic hydrogel electrolyte
Nanostructures Fabrication by Template Deposition in Anodic Alumina Membranes
Elettrodeposizione di leghe nanostrutturate a base di stagno
Characterization of Sn-Co nanowires grown into alumina template
Nanowires of Sn-Co alloys were grown inside the channels of anodic alumina membrane by potentiostatic deposition. The scanning electron microscope images showed the formation of cylindrical nanowires whose height was increasing with deposition time. The X-ray patterns did not show significant diffraction peaks, suggesting the formation of amorphous phases. The higher content of Co in the nanowires, in comparison to the initial composition of the electrolytic bath, was attributed to a higher rate of Co electrodeposition. These nanowires seem to possess specific features suitable for innovative application in the field of Li-ion batteries due to their dimensional stability and high specific s…
Synthesis and characterization of nanostructured materials applied to energy devices
Electrochemical Fabrication of Sn-Co Nanowires in Anodic Alumina Templates
Processo di produzione di filamenti nanometrici in lega amorfa Sn-Co
Nanostructures of different oxides/hydroxides grown in nanoporous templates by electrochemical methods.
SnCo nanowire array as negative electrode for lithium-ion batteries
Abstract Amorphous SnCo alloy nanowires (NWs) grown inside the channels of polycarbonate membranes by potentiostatic codeposition of the two metals (SnCo- PM ) were tested vs. Li by repeated galvanostatic cycles in ethylene carbonate-dimethylcarbonate – LiPF 6 for use as negative electrode in lithium ion batteries. These SnCo electrodes delivered an almost constant capacity value, near to the theoretical for an atomic ratio Li/Sn of 4.4 over more than 35 lithiation–delithiation cycles at 1 C. SEM images of fresh and cycled electrodes showed that nanowires remain partially intact after repeated lithiation–delithiation cycles; indeed, several wires expanded and became porous. Results of amorp…
Elettrodo al piombo, metodo per la sua realizzazione ed accumulatore comprendente l’elettrodo
Template electrosynthesis of nanostructures for water electrolysis
Toward Tin-Based High-Capacity Anode for Lithium-Ion Battery
Electrochemical deposition of SnCo alloys inside the nanometric pores of commercial membranes is described. Composition, morphology and crystallographic structure of the synthesized nanostructured alloys are reported as well as the results of electrochemical tests carried out both in half-cell and in full battery configuration to investigate the performance of these SnCo alloys as anodes for lithium-ion batteries. Optimized depositions yielded nanostructured alloys that performed 200 deep galvanostatic cycles at C/2 and 30 °C with 80 % capacity retention and coulombic efficiency higher than 97 % after 40 cycles Moreover, charge-discharge rate capability tests showed the high performance of …
CulnSe2/Zn(S,O,OH) junction on Mo foil by electrochemical and chemical route for photovoltaic applications
Electrodeposition is a convenient technique for the development of low cost materials for photovoltaic (PV) device processing. Using a single step electrodeposition route, several groups have fabricated CIS (CuInSe) and CIGS (CuInGaSe) films [1]. One of the most important requirements for successful application of one-step electrodeposition film formation, is the ability to control composition of the deposited films and to develop polycrystalline microstructures with a low surface roughness and high sintered density. In this preliminary work, CIS films were produced by single bath electrodeposition finding the optimal conditions in order to achieve a dense film with high crystallinity and u…
Nanostructured Material Fabrication for Energy Conversion
Metal displacement deposition: a new route for template fabrication of metal and metal oxide nanostructures
Nanostructured Material Fabrication for Energy Conversion
The electrochemical deposition is a suitable via to fabricate nanostructured materials for energy conversion, and for other purposes. This paper deals with the electrochemical synthesis of nanostructured alloys and ruthenium oxide, which can be used in Li-ion batteries and polymer electrolyte membrane electrolyzers.
Nanostructured anode material for Li-ion batteries
The present paper focuses on a nanostructured SnCo alloy electrochemically prepared by template method in view of its use as anode material alternative to graphite in lithium-ion batteries. The fabrication of SnCo nanowire arrays was carried out by potentiostatic co-deposition of the two metals by using nanostructured anodic alumina membranes as template. Electrochemical tests on lithiation-delithiation of these SnCo electrodes in conventional organic electrolyte (EC:DMC LiPF6) at 30°C showed that their specific capacity was stable for about the first 12 cycles at a value near to the theoretical one for Li22Sn5 and, hence, progressively decayed.
Novel acidic hydrogel electrolytes based on PVA and PVA blends
Fabrication of Metal Oxide Nano-structured electrodes by Template Electrosynthesis
Metodo di realizzazione di un elettrodo ad elevata densità energetica ed elettrodo ottenibile con tale metodo
Electrochemical and chemical synthesis of CIS/Zn(S,O,OH) for thin film solar cells
In this work, we are reporting results on the electrodeposition of the CuInSe2 thin films on molybdenum thin foil substrates. We have used an aqueous non-buffered electrolyte and a careful choice of deposition parameters to ensure a good quality and composition of the deposited films. In addition, CdS was replaced in the buffer layer with a wider bandgap Zn(S,O,OH) film obtained by chemical bath deposition. The deposited films were annealed in inert atmosphere at different temperatures. The influence of annealing temperature on the properties of the films is briefly discussed. Films were also characterized by photoelectrochemical and I-V measurements. Structural characterization was carried…
A new route to grow oxide nanostructures based on metal displacement deposition. Lanthanides oxy/hydroxides growth
Abstract A metal displacement reaction has been used in order to cause precipitation of oxide nanostructures within pores of anodic alumina membrane (AAM) templates. Here, we focus on the displacement deposition of LnO/OH (Ln = La, Ce, Sm, Er) nanostructures using Zn as sacrificial anode, employing a specific cell arrangement where a galvanic couple was formed between zinc anode and the Au thin layer covering template pore bottom. Progress of displacement deposition reaction into template channels was monitored measuring the open circuit potential as well as pH changes of the electrolyte. A progressive de-activation of the anode surface was observed for long deposition times, caused by depo…
FUNZIONALIZZAZIONE DI MEMBRANE ANODICHE DI ALLUMINA PER LA FABBRICAZIONE DI NANOSTRUTTURE DI INTERESSE TECNOLOGICO
A viable path toward a high energy density anode for lithium-ion batteries
Template Electrosynthesis of SnCo Nanowire Arrays for Lithium-ion Batteries
Monodimensional Amorphous SnCo Arrays As High Performing Anodes for Lithium Ion Batteries
Nanostructured anode and cathode materials for Li-ion batteries
Sintesi per via elettrochimica di nanowires di leghe Co-Sn
Metal Displacement Deposition: a facile via to grow metal and metal oxide nanostructures
Nanostructured materials have received increasing attention because of their high chemical reactivity that allows an extensive use in many fields, like catalysis, electrosynthesis, sensors, and so on [1]. Taking into account that size plays a fundamental role for the properties of nanostructures, it is of relevant importance for their applications to develop a facile method of synthesis. In our previous works, we have described a template synthesis of metal nanowires through a simple novel route [2-4]. In particular, using a combination of template deposition and metal displacement reaction, we have fabricated pure metal nanowires with a well-defined morphology. This type of template synthe…
One-dimensional nanostructures of lead and lead dioxide for application in lead-acid batteries
Fabrication of Pb and PbO2 nanostructures was undertaken with the aim of building low cost lead acid micro-batteries with high performance. Despite environmental problems and the relatively low specific energy in comparison with other galvanic generators, lead acid batteries are still extensively used in the field of energy accumulation, owing to a well known and reliable technology. Thus, it is of high technological interest to develop procedures for fabricating these devices at a micrometer scale or less. PbO2 nanowires were grown in different electrochemical deposition conditions leading to pure -PbO2, pure -PbO2 and mixture [1-2]. Several parameters, like temperature, electrolyte…
Electrosynthesis of Sn-Co nanowires in alumina membranes
A fabrication process of amorphous nanowires of Sn-Co alloys, based on electrodeposition into anodic alumina membranes, is described. It is shown that nanowires of tin-cobalt alloys with different compositions can be produced by varying electrodeposition time and concentration ratio of salts dissolved into the electrolytic bath. Importance of the chelating agent to produce amorphous Sn-Co alloys has also been addressed. Electrodepositions were carried out potentiostatically at -1 V versus Saturated Calomel Electrode and 60 degrees C for times ranging from 10 to 90 minutes; the atomic fraction of Co2+ in the aqueous electrolyte (Co2+/(Co2+ + Sn2+)) was varied from 0.33 to 0.67. Nanowires asp…
Effect of temperature on the growth of alfa-PbO2 nanostructures
Abstract Ordered arrays of α-PbO 2 nanostructures were grown by galvanostatic anodic deposition into the channels of alumina templates. Electrodepositions were performed in an aqueous solution containing lead acetate and sodium acetate at pH 5.4. Bath temperature and electrodeposition time were varied to check their effect on the growth of nanostructures. It has been found that filling of alumina pores is independent of the time and electrodeposition temperature, whilst height and growth kinetics of nanostructures vary with both parameters. Temperature greatly influences morphology: wires grown at room temperature consisted of clusters of particles, leading to poorly compact structures, whi…
Ruthenium Oxide Nanotubes Via Template Electrosynthesis
Ruthenium oxide nanotubes were fabricated by a single-step galvanostatic deposition using porous anodic alumina membrane as template. For the electrodeposition process, we used a electrochemical cell specifically designed in order to employ only 0.5 ml of 0.02 M RuCl3•xH2O solution. The deposition from a very small volume was specifically addressed owing to the high cost of ruthenium compounds, which could be of some relevance from an applicative point of view. Several techniques were used to characterize the samples prior to and after thermal treatment, which was carried out at different temperatures in order to study the crystallization process of the deposit. Raman spectroscopy of as-dep…
One-dimensional nanostructures as electrode materials for water electrolysis
Metallic lead recovery from lead-acid battery paste by urea acetate dissolution and cementation on iron
Abstract A suitable hydrometallurgical and environmentally friendly process was studied to replace the currently used practices for recycling lead-acid batteries via smelting. Metallic lead was recovered by cementation from industrial lead sludge solutions of urea acetate (200 to 500 g/L) using different types of metallic iron substrates (nails, shaving or powder) as reducing agents. Under specific operating conditions, up to 99.7% of lead acid battery paste, mainly composed of PbSO4, PbO2 and PbO·PbSO4 species, was converted to metallic lead.. The conversion of the metallic lead and rate of the cementation reaction were strictly dependent on the type of iron substrate used as the reductant…
Nanostructured alloys for energy devices
Raman spectroscopy of lead dioxide nanowires
Fabbricazione elettrochimica e caratterizzazione di materiali nanostrutturati
High-performing Sn-Co nanowire electrodes as anodes for lithium-ion batteries
Abstract The preparation of Sn 2 Co 3 nanowire arrays (NWs) electrogrown inside the channels of polycarbonate membranes and their characterization as anodes for Li-ion batteries both in half-cell vs. Li and in battery configuration are reported. The Sn 2 Co 3 NW electrodes tested by deep galvanostatic charge/discharge cycles in ethylene carbonate-dimethylcarbonate (1:1) – LiPF 6 1 M displayed 80% capacity retention after 200 cycles at C/2 and 30 °C, and a high charge and discharge rate capability at C-rate from C/3 (0.33 A/g) to 10C (10 A/g) at 30° and 10 °C. Electrodes with the highest alloy loading delivered up to 0.6 mAh cm −2 at C/2. The performance of these electrodes in battery config…
Characterization of Thin Film Cig(S,Se)2 Submodules Using Solar Simulator and Laser Beam Induced Current Techniques
In this work, the electrical and optical characterization of CIG(S,Se)2 sub-modules using both a solar simulator equipment and the Laser Beam Induced Current (LBIC) technique is presented. By using the solar simulator and a proper set-up, the electrical parameters of the modules at varying irradiance and temperatures are determined. In addition, the LBIC measurements are carried out to analyze the 2D photocurrent uniformity of the modules at two different wavelengths. Dispersion values of extracted parameters can be very useful for practically tuning the modelling stage at device/module level.
Lead Electrode, Method for its Manufacturing and Accumulator Comprising the Electrode
Sn-Co nanowire-based anodes for lithium-ion batteries
The demand of improvement in lithium-ion battery technology in terms of specific capacity and safety has stimulated the search for anode materials alternative to graphite. Among them, tin-based materials have been widely studied because tin can intercalate lithium up to atomic ratio Li/Sn of 4.4 to deliver a impressive specific capacity of 993 mAhg−1 (while graphite gives 372 mAhg−1). Unfortunately the high volume change of about 300%, which is related to the insertion/removal of lithium, causes the alloy pulverization and loss of electric contact that causes a poor cycle life. The synthesis of nanometric materials, intermetallic compounds and carbon composites are strategies that have been…
Method for Producing an Electrode with Nanometric Structure and Electrode with Nanometric Stucture
Investigation of Annealing Conditions on Electrochemically Deposited CZTS Film on Flexible Molybdenum Foil
In thiswork, the electrodeposition of Cu2ZnSnS4 thin films on molybdenum thin foilwas reported. In order to guarantee co-deposition of elements with different standard electrochemical potential, an aqueous electrolyte added with ligand agents was used. I addition, deposition parameters were carefully chosen, in order to ensure good quality and suitable composition of the films. The deposited films were sulfurized in controlled atmosphere at 580?C, scrutinizing the influence of the annealing conditions on the features of the films. Structure, morphology and composition were investigated by XRD SEM, EDS and Raman spectroscopy. Results reveal the growth of good quality films, with a uniform mo…
CuInSe2/Zn(S,O,OH) junction by electrochemical and chemical route for photovoltaic applications (GE 2014)
Electrodeposition is a convenient technique for the development of low cost materials for photovoltaic (PV) device processing. Using a single step electrodeposition route, several groups have fabricated CIS (CuInSe) and CIGS (CuInGaSe) films. One of the most important requirements for successful application of one-step electrodeposition film formation is the ability to control composition of the deposited films and to develop polycrystalline microstructures with a low surface roughness and high sintered density.