Thick-film Electrodes Research Articles

Li-insertion/extraction Properties of Si Thick-film Anodes in Ionic Liquid Electrolytes Based on Bis(fluorosulfonyl)amide and Bis(trifluoromethanesulfonyl)amide Anions

Abstract Charge–discharge cycling performances of Si thick-film electrodes as Li-ion battery anodes were investigated in several ionic liquids based on bis(fluorosulfonyl)amide (FSA) and bis(trifluoromethanesulfonyl)amide (TFSA) anions. The Si electrodes in FSA-based electrolytes exhibited much better performance than those in TFSA-based electrolytes. An easier desolvation of Li from anions on the electrode surface is probably promoted in FSA-based electrolytes, which enables efficient electrode reactions of Li-insertion/extraction and improvement of cycling performances.

Improved Anode Performance of Ni-P-Coated Si Thick-Film Electrodes for Li-Ion Battery

To improve the deviation of cycling performances as Li-ion battery anode, we controlled the morphology of Ni-P layers deposited on Si particles in thick-film electrodes prepared by a gas-deposition method. The spotty Ni-P layers were uniformly coated on Si particles by an electroless deposition in a neutral bath. The resulting electrodes using Ni-P-coated Si exhibited excellent cycling performances and their good reproducibility. The reason for the improvement of performances is probably that the Ni-P layers can effectively release a stress generated by alloying/dealloying reactions of Li with Si.

Novel Composite Thick-Film Electrodes Consisted of Zinc Oxide and Silicon for Lithium-Ion Battery Anode

Novel Composite Thick-Film Electrodes Consisted of Zinc Oxide and Silicon for Lithium-Ion Battery Anode

A comparison study of pattern recognition algorithms implemented on a microcontroller for use in an electronic tongue for monitoring drinking waters

A portable electronic tongue has been developed using an array of eighteen thick-film electrodes of different materials forming a multi-electrode array. A microcontroller is used to implement the pattern recognition. The classification of drinking waters is carried out by a Microchip PIC18F4550 micro-controller and is based on neural networks algorithms. These algorithm are initially trained with the multi-electrode array on a Personal Computer (PC) using several samples of waters (still, sparkling and tap) to obtain the optimum architecture of the networks. Once it is trained, the computed data are programmed into the microcontroller, which then gives the water classification directly for new unknown water samples. A comparative study between a Fuzzy ARTMAP, a Multi-Layer Feed-Forward network (MLFF) and a Linear Discriminant Analysis (LDA) has been done in order to obtain the best implementation on a microcontroller.

Influence of order in stepwise electroless deposition on anode properties of thick-film electrodes consisting of Si particles coated with Ni and Cu

Nickel and copper were coated on Si particles by a stepwise electroless deposition technique in which the coating orders of the metals were exchanged. Thick-film electrodes for Li-ion batteries were prepared by a gas-deposition method using the coated Si particles, and the anode performance of these electrodes was investigated. For (Cu, Ni)-coated Si particles obtained by primary Cu deposition and successive Ni deposition, Cu and Ni metal layers were individually deposited on the Si particles. In contrast, in case of (Ni, Cu)-coated Si particles prepared by primary Ni deposition, Cu layer stacked on Ni layer owing to a high catalytic activity of Ni, forming a thicker coated layer. The latter electrode exhibited notably improved performance with the discharge capacities over 1000 mAh g −1 maintained until 400th cycle. The layer stack of Cu on Ni is probably effective for a release of a stress from the Si particles during charge–discharge reactions.

Thick-Film Electrodes Consisted of Si and Transition Metal Silicides Prepared by Gas-Deposition for Anodes of Li-Ion Batteries

not Available.

Anode Properties of Composite Thick-Film Electrodes Consisted of Si and Various Metal Silicides

Anode Properties of Composite Thick-Film Electrodes Consisted of Si and Various Metal Silicides

Low temperature co-fired ceramic (LTCC)-based biosensor for continuous glucose monitoring

This article presents design, fabrication and testing of a miniature ceramic-based biosensor which is destined for continuous glucose monitoring. It is fabricated using well known LTCC (low temperature co-fired ceramics) technology. The biosensor consists of a microreaction chamber, three thick-film electrodes and a microdialysis tube. The detection process is based on oxidation of glucose by molecular oxygen in the presence of enzyme – glucose oxidase, GO x. One of the reaction products is a hydrogen peroxide which is detected amperometrically during its oxidation at a working electrode. Computational fluid dynamics (CFD) analysis was used for optimization of the biosensor geometry and considerations of the influence of operating conditions (flow rate) on mass transfer (diffusion) of the glucose within the microreaction chamber. Tests of the developed LTCC-based biosensor indicate its linear response to glucose concentration up to 9 mM with a relatively high sensitivity of about 147 nA/mM. Moreover, the properties of the presented ceramic biosensor are compared with properties of a similar device made in silicon/glass and in Perspex ®.

Application of electrolyte using novel ionic liquid to Si thick film anode of Li-ion battery

An applicability of a novel ionic liquid, consisting of 1-methoxyethoxymethyl(tri- n-butyl)phosphonium cation and bis(trifluoromethanesulfonyl)amide anion, was investigated as an electrolyte of Li-ion battery using a thick film electrode of Si prepared by a gas-deposition method. The electrochemical properties in the novel ionic liquid were compared to those in a commercial ionic liquid and a typical organic solvent of propylene carbonate. The initial discharge capacity of 3450 mAh g −1 and excellent cycling performance were achieved in the novel ionic liquid. The novel ionic liquid was confirmed to effectively suppress a collapse and an electrical isolation of the Si thick film induced by pulverization during charge–discharge cycling. The excellent performance is possibly attributed to more effective desolvation of Li ions from the anions due to its lower dielectric constant compared with the propylene carbonate solvent.

A 0.5-$\mu$V$_{\rm rms}$ 12-$\mu$W Wirelessly Powered Patch-Type Healthcare Sensor for Wearable Body Sensor Network

A wirelessly powered patch-type healthcare sensor IC is presented for a wearable body sensor network (W-BSN) to continuously monitor personal vital signals. Thick-film electrodes are screen printed on a fabric by planar-fashionable circuit board (P-FCB) technology on which stainless steel powder with a grain size of 100 μ m is added to reduce both contact impedance as well as motion artifacts. A nested chopped amplifier (NCA) is designed and optimized for the proposed patch-type healthcare sensor with a reduced electrode referred noise of 0.5 μVrms. A programmable gain and bandwidth amplifier (PGA) stage is also implemented to accommodate various dynamic ranges of vital signals. A 10-b folded successive approximation register (SAR) analog-to-digital converter (ADC) reduces capacitive digital-to-analog conversion size by 94% and relaxes the power budget of the ADC driver by 36%. Measured sensor resolution is 9.2 b and rejects common-mode interference larger than 100 dB while consuming only 12 μ W of power supplied wirelessly. A 2.0 mm × 1.3 mm sensor IC is fabricated in 0.18-μm 1P6M CMOS technology. The chip is directly integrated between two screen printed electrodes and stacked by a screen printed fabric inductor. With the proposed patch-type sensor, personal healthcare without expensive batteries is possible in W-BSN and greatly improves wearability and convenience in use.

Anode properties of thick-film electrodes prepared by gas deposition of Ni-coated Si particles

Thick-film electrodes of Si particles coated with Ni, Ni–Sn, and Ni–P were fabricated by electroless deposition followed by gas deposition to form the anode of a Li-ion battery. The electrode of Ni-coated Si showed remarkably improved cycling performance with a discharge capacity of 580 mA h g −1 at the 1000th cycle, which is possibly caused by its higher elastic modulus than that of the uncoated Si electrode. The electrode of Si coated with Ni–P, which consisted of Ni 3P, with the lower coating amount exhibited a higher initial capacity and excellent cycling performance with a capacity of 790 mA h g −1 at the 1000th cycle, whereas poor performance was obtained for the electrode of Si coated with Ni–Sn. The excellent performance in the case of Ni–P coating is attributed to the smaller amount of coating, the high elastic modulus, and the lower reactivity of Ni 3P with Li ions in comparison with Ni 3Sn in Ni–Sn.

Electrolytic sensor for trace level determination of moisture in gas streams

A thin film platinum electrode-based electrolytic moisture sensor for the measurement of lower concentrations of moisture in gas streams with flow rates lesser than 5 ml/min was designed. The thin film electrode was fabricated with pulsed laser ablation technique and screen printing. The PL-ablated electrode showed deterioration after 80 h of operation. The screen-printed thick film electrode sustained for more than 12 months. The response of the sensor was absolute and so the electrolytic and non-electrolytic currents were deduced. The sensor recovery time from either extreme dry or moist conditions was 70 s. The concentration of trace moisture in an argon cylinder was identified using the present design and the values were found to be 3.97 ± 0.07 ppm at cylinder pressure of 150 kg/cm 2 and 37.41 ± 0.27 ppm at 30 kg/cm 2. In addition to the sensitivity up to 1 ppm the present design could detect the sensor failure during operation.

Parameters affecting the sensitivity of LTCC pressure sensors

Purpose – The purpose of this paper is to demonstrate the influence of material properties and fabrication technique on the performance of an embedded pressure sensor. Based on conducted theoretical analysis a suitable material and technological technique that gave the best behavior of designed sensor was chosen for its fabrication. This is verified on the example of a resonant pressure sensor, designed for operation in the MHz range.Design/methodology/approach – A sensor module is fabricated using the low temperature co‐fired ceramics (LTCC) technology and sputtering technique for electrodes deposition. The module comprises an inductor connected with a variable capacitor formed by the sensor membranes in a parallel LC circuit. An extensive parallel analysis of sensors performance for sensors with thick film (screen‐printed) and thin film (sputtered) electrodes is demonstrated. Mechanical and electrical parameters (Young's modulus and permittivity) of different tape materials that are considered for senso...

Reaction mechanism of tin nitride (de)lithiation reaction studied by means of 119Sn Mössbauer spectroscopy

Tin nitride thin films have been reported as promising negative electrode materials for lithium-ion solid-state microbatteries. However, the reaction mechanism of this material is not yet fully understood. Results on thin film electrodes pointed out that the conversion mechanism of tin nitride most likely differs from the conversion mechanism usually observed for other oxide and nitride conversion electrode materials. The electrochemical data showed that more than six Li per Sn atom can be reversibly exchanged by this material while about four are expected. In order to investigate in more detail the reaction mechanism of tin nitride, thick film electrodes of two compositions (1:1 and 3:4) have been studied. The as-prepared materials were characterized by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy and 119Sn Mössbauer spectroscopy. Moreover, films (de)lithiated to various extents were analyzed ex situ with Mössbauer spectroscopy. The corresponding results indicate that a more complex reaction mechanism than that generally accepted takes place. During Li-ion insertion, the disappearance of Sn 4+ environments is correlated with the formation of Li–Sn phases, and most likely also of Li 3N. In the case of the SnN x 1:1 composition films, the formation of various Li–Sn phases is evidenced while only the signature of ‘Li 22Sn 5’ is clearly measured for the 3:4 composition. Upon Li-ion extraction, the Li–Sn phases and Li 3N recombine to form octahedrally and tetrahedrally coordinated Sn 4+. The extraction is not fully reversible and the end product consists of a mixture of a tin nitride structure plus a Li y Sn product having the same isomer shift as LiSn but a much higher quadrupole splitting, and most likely some Li 3N.

A voltammetric sensor on the basis of bismuth nanoparticles prepared by the method of gas condensation

A procedure is developed for the immobilization of bismuth nanoparticles prepared by the method of gas condensation on inert supports manufactured by the screen printing method using carbon-containing inks. The electrochemical behavior of the immobilized bismuth nanoparticles is investigated, and the conditions of their electrochemical activation are found. The composition of the modifying suspension “bismuth nanoparticles-liquid” is optimized. The elaborated thick-film carbon-containing electrode modified by bismuth nanoparticles is shown to be similar in its analytical parameters to the commercially available thick-film carbon-containing electrode premodified by calomel, and substantially exceeds carbon-containing electrodes with electrolytically deposited bismuth films in its properties. The limits of detection for heavy metals by stripping voltammetry are as follows (μg/L): 0.38 for Zn(II), 0.40 for Cd(II), and 0.55 for Pb(II) at the preconcentration time 180 s.

Anode Properties of Ni-Coated Si Thick Film Electrodes Prepared by Gas-Deposition

not Available.

Advanced Use of Nanobismuth/Nafion Electrode for Trace Analyses of Zinc, Cadmium, and Lead

Trace analyses of zinc, cadmium, and lead at a surface-modified thick-film graphite electrode with bismuth nanopowder have been carried out using the square wave anodic stripping voltammetry (SWASV) technique. For strong adhesion of the bismuth nanopowder onto the screen-printed carbon paste electrode, a Nafion solution was added to the bismuth-containing suspension. From the analyses of the zeta potential and the scanning electron microscopy image of the electrode surface, it is suggested that Nafion plays an important role in the homogeneous distribution of bismuth nanoparticles as well as in creating a strong chemical bond between them. To maximize the electrochemical characteristics of the nanobismuth/Nafion electrode, the optimum conditions of SWASV and the nanobismuth labeling amount were suggested. The sensitivity and detection limit of the nanobismuth/Nafion electrode were quantitatively estimated from the analyses of stripping voltammograms. The proposed “mercury-free” carbon strip electrode, modified with bismuth nanopowder, is conveniently usable and directly applicable to a trace metal analysis without predeposition of bismuth and complicated surface polishing steps.

Disposable blood potassium sensors based on screen-printed thick film electrodes

A sensor based on the screen-printing technique for the rapid blood potassium test was developed. The sensor consists of a thick film potassium ion-selective electrode and a reference electrode. Poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly(styrenesulfonate) (PSS) was screen-printed on carbon electrodes as an internal solid contact layer for both ion-selective and reference electrodes. PVC membranes with and without selective ionphore valinomycin were coated on the PEDOT/PSS layer to form potassium ion-selective and reference electrodes, respectively. The potentiometric response characters were evaluated. The response time of the sensor was 15 s when less than 15 µL of sample was applied. The sensitivity of the potassium sensor was around 60 mV per decade, while the potentiometric log selectivity coefficients were −3.43 and −3.48 for Na+ and Ca2+, respectively.

Detection of Adenosine Deaminase Activity with a Thick-Film Screen-Printed Ir/C Sensor to Detect Liver Disease

An electrochemical biosensor, comprising a thick-film screen-printed Ir/C working and counter electrodes, was developed for the detection of the enzymatic activity of adenosine deaminase for potential patient management with liver disease. Present methods of detecting adenosine deaminase involve spectrometric methods that require costly, nonportable equipment that is ill-suited for a point-of-care testing. Studies dealing with the electrochemical detection of adenosine deaminase intermediates such as xanthine and hypoxanthine required the use of , vs a Ag/AgCl reference electrode, and a large sample volume, 1 mL or more. The proposed biosensor used a sample volume of and a potential of vs Ag/AgCl. This biosensor used the enzymes xanthine oxidase (EC 1.1.3.22) and purine nucleoside phosphorylase (EC 2.4.2.1) coimmobilized on the thick-film screen-printed working electrode to detect enzymatically generated . Constant potential measurements showed that this biosensor had good linear performance over a 0–36 units/L of adenosine deaminase concentration range in phosphate buffer, mouse plasma, and mouse whole blood. The effect of the variation in the quantity of enzyme on the current output and the interference from intermediate-formed compounds were also explored.

Anode Properties of Cu-Coated Si Thick Film Electrodes Prepared by Electroless Deposition and Gas-Deposition

Thick film electrodes of Cu-coated Si particles were fabricated by an electroless deposition and a successive gas-deposition, and were evaluated their electrochemical properties as an anode of Li-ion battery. The discharge capacity and its retention at the 1000th cycle were 570 mAh g−1 and 61%. The excellent cycle life performance is attributed to an enhanced electrical conductivity due to the Cu-coating and a reversible conversion reaction between Li and Cu2O which was formed on the Cu surface. The high capacity retention is caused by a high fracture toughness of the coated Cu which can effectively relax a stress induced by volume expansion of Si as a buffer matrix.