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Ethanol is the most alcohol used in daily life. Ethanol can be found in drinks, cosmetics, medicines, flavorings, and many more. Each product requires a different concentration of ethanol. Ethanol concentration can be measured using conventional alcohol meter, but requires a large number of samples and mistaken from reading the measurement can occur. This study aims to make a potentiostat based on the microcontroller to determine ethanol concentration that is easy and accurate. Potentiostat consists of several components of resistors, capacitors, operational amplifiers, and Arduino Mega 2560. Measurements were carried out using the electrochemical analysis fixed potential amperometry which the fixed potential was determined by linear sweep voltammetry. Carbon (C) is used on the working electrode and counter electrode which act as the sensor. From the test results obtained a negative relationship between the increasing concentration against current with a correlation coefficient 0.9998. The level of precision and accuracy of the device that has been made shows good results. The level of precision represented by the mean relative standard deviation (MRSD) obtained a result of 95.18%. While the accuracy value represented by the root mean square error (RMSE) results of 97.08%.

A compact electrochemical cell capped with a silicon nitride (SiN) film of 50 nm thick as an electron window was developed for a side-entry holder of a high-resolution scanning electron microscope (SEM). Electrodeposition and stripping of lead (Pb) were examined on a gold electrode formed on the SiN film, which was faced inside the cell filled with an aqueous solution of lead nitrite. The SEM images of growth and dissociation of Pb were recorded simultaneously with cyclic voltammograms, controlled with a two-terminal potentiostat. Particulate growth of Pb at the edge of a gold (Au) electrode was observed at the underpotential deposition of Pb, followed by dendrite growth of Pb at higher deposition potentials. The growth mode changed depending on the edge morphology of the Au electrode. This indicated that in-situ microscopic observation was invaluable for understanding the phenomena of electrodeposition in electrochemistry.

Designing with a Programmable System on a Chip (PSoC) allows for entire circuit designs to be implemented with a single commercially available chip and eliminates the need to physically assemble electronic components. This is possible as the PSoC incorporates a microcontroller with digital and analog components into a single package. While this design allows for much easier implementation of circuits, there are some drawbacks. In this paper we will demonstrate one of those drawbacks, high routing resistance in parts of the analog mesh that connects the analog parts and external pins. We show how this resistance can cause measurement errors when the PSoC is implemented as a single chip potentiostat. As the internal analog routing resistance is in the kΩ range, measuring currents in the Kॅ range can cause mV errors, leading to lose of voltage control during electrochemical experiments. We also demonstrate a calibration routine to compensate for this voltage error that reduced the error by over 90%.

In order to study the corrosion resistance of the stainless steel bars under marine environmental attack, simulated seawater drying and wetting test on the two types of the stainless steel bars (SSRs), 304 and 316L austenitic SSRs as well as S32304 and S32205 duplex SSRs, was carried out in the laboratory. Electrochemical monitoring of open-circuit potential, linear polarization and electrochemical impedance spectroscopy (EIS) was carried out via CS310H electrochemical potentiostat. Zview software was used to discuss the measured data. Results show that the Stern-Genry coefficient B of the ordinary carbon steel bar is about 20mV, while those values of the duplex SSRs and austenitic SSRs are in the range of 14∼16mV and 15∼17mV, respectively. For the above-listed reinforcement, better corrosion resistance is shown in the duplex SSRs with the best behaviour observed in S32304 duplex SSRs; the corrosion resistance of the austenitic SSRs 304 and 316L is good and similar, while poor corrosion resistance is shown in the ordinary carbon steel bar as expected.

This article reports a portable potentiostat based on a three-electrode electrochemical measurement system, which can be powered and communicated through the OTG interface of a smartphone. The system includes the design of the board-level potentiostat circuit, the generation of excitation in common forms required in electrochemical reactions, and the design of signal capture and analysis circuits. The potentiostat applies the positive and negative step-shaped excitations generated by the excitation generating circuit between the working electrode and the reference electrode stably. Through special excitation methods, the stripping current measured by the working electrode is consistent with that of a large electrochemical workstation. By simulating the classical three-electrode electrochemical solution environment impedance model, the constant potential error of the potentiostat was finally tested to be below 30mV through the detection circuit.

Titanium and its alloys are preferred materials used for medical devices manufacturing due to their specific properties. The corrosion behavior in artificial saliva of the newly developed Ti-Mo-W alloys, with elastic modulus closer to the human bone value was studied by means of linear polarization technique in the following steps: i) measurement/monitoring of open circuit potential (EOC) over 6 hours; ii) tracing linear polarization curves from ±200 mV (vs. OCP) - Tafel plots, with a scan rate of 0.167 mV/s. Electrochemical tests were performed according to ASTM G59-97 (2014)using a Potentiostat/Galvanostatto which a low current interface (LCI) was coupled. The tests were performedin Fusayama Meyer artificial saliva with a pH of 5.2 at the human body temperature (37±0.5°C) which mimic the oral environment. The results indicate that the alloys Ti15Mo7W and Ti15Mo11W have better corrosion behavior than Ti6Al4V.

Over the past several decades since the invention of the first biosensor based on the Clark-oxygen electrode for glucose, the instrument most used for measuring for biosensor devices has been the potentiostat, and there have been thousands of published papers on electrochemical biosensors using the potentiostat. Here, we show for the first time a comparison between a potentiostat and a source measure unit (SMU) for signal generation in a biosensing measurement of glucose. The results demonstrated that both a potentiostat and a SMU could provide excellent sensing performances, though the results were slightly difference. We expect that this work can open up exciting opportunities for fundamental studies on the measurement methods of biosensing devices, as well as for a variety of applications for using biosensing devices in healthcare, environmental monitoring, and defense.

ZnWO4/TiO2 composite films were fabricated on TiO2 substrate by hydrothermal method. The ZnWO4 nanorods-sensitized TiO2 coupled with 304 stainless steel was served as photoelectrode to study its anticorrosion effect for metal. Under visible light, the photocathodic protection ability of TiO2 and ZnWO4/TiO2 composite film was measured by photoelectrochemical program on potentiostat. Open circuit potential variation result showed that sanmartinite ZnWO4 nanorods could enhance the photoelectrochemical activity of TiO2, and the ZnWO4/TiO2 composite films could absorb energy and store electrons to play a role in corrosion protection for metal.

The present paper shows the effect of heat treatments applied to an AISI 420 steel. The characterization of corrosion behavior of AISI 420 steel, in 0.5M NaCl aqueous solution, was made in an electrochemical cell with 3 electrodes, connected at PG STAT 302N Autolab Potentiostat, at laboratory temperature. The medium used was a NaCl 0.5M solution with a pH of 6.26 and an electro-conductivity by 49.9 mS/cm.

This paper addresses the development of differential pulse voltammetry (DPV) embedded algorithm using an ARM cortex processor with new developed potentiostat circuit design for in-situ 3-electrode cell sensing. This project is mainly to design a low cost potentiostat for the researchers in laboratories. It is required to develop an embedded algorithm for analytical technique to be used with the designed potentiostat. DPV is one of the most familiar pulse technique method used with 3-electrode cell sensing in chemical studies. Experiment was conducted on 10mM solution of Ferricyanide using the designed potentiostat and the developed DPV algorithm. As a result, the device can generate an excitation signal of DPV from 0.4V to 1.2V and produced a peaked voltammogram with relatively small error compared to the commercial potentiostat; which is only 6.25% difference in peak potential reading. The design of potentiostat device and its DPV algorithm is verified.

This paper presents the design of a two-stage operational amplifier(op amp) for 3-electrode sensing system readout circuits. The designs have been simulated using 0.13μm CMOS technology from Silterra (Malaysia) with Mentor graphics tools. The purpose of this projects is mainly to design a miniature interfacing circuit to detect the redox reaction in the form of current using standard analog modules. The potentiostat consists of several op amps combined together in order to analyse the signal coming from the 3-electrode sensing system. This op amp design will be used in potentiostat circuit device and to analyse the functionality for each module of the system.

A low power sensor read-out circuit has been implemented in 0.35 µm CMOS technology that consumes only 400 µW of power and occupies an area of 0.66 mm2. The circuit is capable of converting the current signal from any generic biosensor into an amplitude shift keying (ASK) signal. The on-chip potentiostat biases the chemical sensor electrodes to create the sensor current which is then integrated and buffered to generate a square wave with a frequency proportional to the sensor current level. A programmable frequency divider is incorporated to fix the ASK envelope frequency to be inbetween 20 Hz and 20 kHz, which is within the audible range of human hearing. The entire transmitter block operates with a supply voltage as low as 1.5 V, and it can be easily powered up by an external RF source. Test results emulate the simulation results with good agreement and corroborate the efficacy of the designed system.

A study of TiO2/Ti nanotubes arrays (NTAs) based on Dye-Sensitized Solar Cell (DSSC) used Asphalt Buton (Asbuton) extract and methylene blue (MB) as a photosensitizer dye has been conducted. The aim of this research is that the Asbuton extract and Methylene Blue (MB) performance as a dye on DSSC solar cells is able to obtain the voltage-currents produced by visible light irradiation. Electrode TiO2/Ti NTAs have been successfully synthesized by anodizing methods, then characterized by using XRD showed that the anatase crystals formed. Subsequently, the morphology showed that the nanotubes formed which has coated by Asbuton extract. The DSSC system was formed by a sandwich structure and tested by using Multimeter Digital with Potentiostat instrument. The characteristics of current (I) and potential (V) versus time indicated that the Asbuton was obtained in a high-performance in 30s of 14,000µV; 0.844µA, meanwhile MB dyes were 8,000µV;0.573µA. Based on this research, the Asbuton extract from Buton Island-Southeast Sulawesi-Indonesia was potential for natural dyes in DSSC system.

Preparation of manganese (Mn) and nitrogen (N)-doped TiO2/Ti electrode as a COD sensor was successfully performed to enhance photoelectrocatalytic activity under visible light. The preparation of Mn and N using the sol-gel method then coated on TiO2 thin layer hidrothermal by dip-coating technique. Characterization of Mn-N-TiO2/Ti electrode using FTIR showed that indicated the Ti-O, Ti-N, N-O, and Mn-O bonds. SEM-EDX showed a thin layer formed of Mn and N on TiO2/Ti surface with the Mn, N, Ti, O spectrums at 0.277 KeV, 0.677 KeV, 4.508 KeV, and 0.579 KeV, respectively. The photoelectrochemical test using a potentiostat was indicated that Mn-N-TiO2/Ti electrode active under visible light which evidenced by photocurrent response.

Ochratoxin A (OTA) is a nephrotoxic metabolite, hepatotoxic and carcinogenic produced mainly by Aspergillus and Penicillium fungi. Usually, the mycotoxin analysed through the technique of high performance liquid chromatography. This method is expensive and takes a lot of time. Therefore, expected to automate a device of low cost, minimal instrumentation micropolarographic (MIMP) for the analysis. For this purpose, the right programming environment and the manufacturing of the software for the graphical user interface selected automation of the MIMP through the design and simulation of the circuit, imprint and assembled in a container with connection ports. Lastly, validation and analysis of Ochratoxin A by cyclic voltammetry from analogous MIMP, automatic MIMP and a potentiostat, in order to corroborate the registered data. This way, voltammetry analysis of coumarin is obtained and the simulation of the MIMP electric circuit. Therefore, this are the key data during the investigation, because the molecule of OTA can be monitored through an acid hydrolysis of amides, composed by a phenylalanine and coumaric acid group, generating the significant decrease in the costs and time of analysis.

A summary of the state of the art in the development of two submersible voltammetric probes performed by us to allow continuous, real-time monitoring of trace elements (Cu(II), Pb(II), Cd(II), Zn(II) and Mn(II), Fe(II)) in natural aquatic ecosystems is given. The first one, called the voltammetric in situ (VIP) profiling system, allowed in situ measurements in surface water and groundwater down to 500 m. Its construction required the development of: (i) a gel-integrated, either single or interconnected, array microsensor, (ii) a submersible probe and (iii) hardware, firmware and software for control of the whole system: i.e. data transmission and acquisition, data processing and maintenance operations. The second system, called the sediment-water interface voltammetric in situ profiling (SIVIP) system, has been developed to allow real-time, high spatial resolution trace elements concentration profile measurements at the sediment-water interface. Its construction required the development of: (i) a gel-integrated microsensor array with 64 individually addressable lines, (ii) a voltammetric probe based on powerful double multiplexing system and single potentiostat allowing simultaneous measurements over the 64 sensor lines, and (iii) hardware, firmware and software for control of the whole system. A general description of both systems as well as examples of laboratory characterization and/or field applications are reported.

The use of four-electrode systems in the studies of electric phenomena occurring in membranes makes it possible to reduce errors caused by electrode and electrolyte resistance. A four-electrode potentiostat-galvanostat is described in this paper. It allows for electric measurements of membranes in controlled potential and current conditions or measurements of transmembrane potential. The method of selection of the operation mode of the system is described.

This paper presents a low noise complimentary metal–oxide-semiconductor (CMOS) detection chip for amperometric electrochemical sensors. In order to effectively remove the input offset of the cascaded integrators and the low frequency noise in the modulator, a novel offset cancellation chopping scheme was proposed in the Incremental ΔΣ analog to digital converter (IADC). A novel low power potentiostat was employed in this chip to provide the biasing voltage for the sensor while mirroring the sensor current out for detection. The chip communicates with FPGA through standard built in I2C interface and SPI bus. Fabricated in 0.18-μm CMOS process, this chip detects current signal with high accuracy and high linearity. A prototype microsystem was produced to verify the detection chip performance with current input as well as micro-sensors.

A tetrapolar probe to measure the electrical properties of electrolyte solutions was implemented with gold electrodes according to the van der Pauw method. Electrical impedance spectroscopy (EIS) measurements of different concentrations of phosphate buffer saline (PBS) solution and an oral mucosal tissue sample dispersed in PBS were performed in the galvanostatic mode using a four-electrode cell (tetrapolar probe). Taking advantage of using a potentiostat/galvanostat for carrying out the electrical measurements, a simple and rapid method using a three-electrode electrochemical cell is described for: a) cleaning of electrodes, b) verification of surface chemical state of electrode material and c) choice of current supplied to electrodes for EIS measurements. Results of this research shown a depolarization effect due to the addition of oral mucosa tissue cells into the PBS solution.

The construction of an apparatus for electrochemical investigations using an IBM personal microcomputer is presented. This apparatus can be used in a wide range of electrochemical methods, stationary and dynamic. A special construction solution allows for application in electrochemical impedance spectroscopy measurements, particularly using the fast Fourier transform method. The apparatus contains a potentiostat connected with signal generators for the polarization of the working electrode and two identical analogue-to-digital conversion channels. For data transmission between this apparatus and the microcomputer, two parallel transmission ports and a special communication interface are used. Also, the detailed description of the construction of the analogue-to-digital conversion channels, including a special module for direct voltage compensation in the input analogue signal, is given, together with the final technical specification of the apparatus.

In present study, we prepared nanoporous Ti oxides by potentiostat and pulse dealloying TiCu amorphous alloy in HNO3 solution. The influence of applied voltage on the morphology was investigated by SEM. The mechanism of dealloying was also discussed. A multilayer nanoporous structure was fabricated using pulse dealloying. The ideal nanoporous structure with mean pore diameter of about 50-100 nm and mean pore wall thickness of about 50 nm was obtained using pulse dealloying with initial voltage of 1.0 V and pulse size of 0.4 V. The static currents for pulse dealloying are higher than those for potentiostat dealloying under the same initial potentials. The nanoporous surface is mainly composed of TiO, Ti2O3 and TiO2.

In this paper, we demonstrate that mechanically modified cylinder-shaped carbon nanotube (CNT) working electrodes (WEs), combined with an averaging processing algorithm, can increase electrogenerated chemiluminescence (ECL) limit of detection by more than one order of magnitude, compared to gold electrodes. With CNT WEs, we obtained a stable light emission that lasts for hundreds of voltammetric cycles. This stability was further exploited to increase the detection limit with a simple algorithm, based on mean calculation. Ad hoc fabricated sensors are characterized with a full-custom potentiostat testbed and software platform, using tris(2,2-bipyridyl)ruthenium (II) as ECL labels. Our measurement results show that the signal-to-noise ratio (SNR) improves by a factor of larger than 20 compared to standard gold WEs to reach a detection limit up to 40 pg ?l?1.

We report a compact electrochemical sensing system to implement cyclic voltammetry. This type of sensor needs a working electrode, counter electrode, and reference electrode, all of which were integrated on a single chip. The electrochemical system also needs a potentiostat and an input voltage-generating circuit, which were developed using on-chip active devices and a few discrete passive components. This is the first sensor system incorporating electrode-side input voltage generation for electrochemical measurements using an on-chip operational amplifier, which replaces a bulky external voltage controller. A continuous cyclic voltammetry measurement was conducted with a well-studied ferricyanide solution to demonstrate the operation of the intelligent sensor chip. A clear peak was observed and linearity to the target chemical concentration was obtained between the peak height and concentration of the ferricyanide solution. With potential for mass production and small size, this sensor chip could be the best candidate to realize point-of-care testing. This sensor chip is a milestone of a fully integrated electrochemical sensor chip.

An electrochemical sensor has been developed on a single chip in which potentiostat and sensor electrodes are integrated. Sensor chips were fabricated using 5.0 µm complementary metal–oxide–semiconductor (CMOS) technology. All processes including the CMOS process, postprocessing for fabricating sensor electrodes and passivation layers, and packaging were performed at Toyohashi University of Technology. The integration makes it possible to measure electrochemical signals without having to use a bulky external electrochemical system. The potential between the working electrode and the reference electrode was controlled using an on-chip potentiostat composed of CMOS transistors. The chip characteristics were verified by electrochemical measurement, namely, by cyclic voltammetry. Potassium ferricyanide solution was measured to obtain results that fit well to the theoretical formula. A clear proportional relationship between peak height and the concentration of the sample solution was obtained using the proposed sensor chip, and the dynamic range obtained was 0.10 to 8.0 mM.

This paper presents a high precision CMOS weak current readout circuit. This circuit is capable of converting a weak current into a frequency signal for amperometric measurements with high precision and further delivering a 10-bit digital output. A fast stabilization-enhanced potentiostat has been proposed in the design, which is used to maintain a constant bias potential for amperometric biochemical sensors. A technique based on source voltage shifting that reduces the leakage current of the MOS transistor to the reverse diode leakage level at room temperature was employed in the circuit. The chip was fabricated in the 0.35 μm chartered CMOS process, with a single 3.3 V power supply. The interface circuit maintains a dynamic range of more than 100 dB. Currents from 1 pA to 300 nA can be detected with a maximum nonlinearity of 0.3% over the full scale.

We investigated the orientation control of photosynthetic reaction center proteins (RCs) by preparing RC Langmuir-Blodgett films in which a DC bias voltage ranging from -0.5 V to +0.5 V was applied (using a potentiostat) during film deposition. The bias voltage was applied between a conductive indium-tin-oxide coated glass substrate and a subphase through a helical platinum counter electrode. The orientation was evaluated using displacement-current measurement and photoelectron spectroscopy. Our results confirm that molecular orientation of RCs in the films was controlled by the polarity of the applied voltage.

Electrochemistry uses current and impedance data to derive chemical rate constants and to obtain information about reaction mechanisms, usually with techniques operating below 100 kHz. By the application of time-domain spectroscopy this region can be extended to nano- or picoseconds and information about the electronic structure of cell components, e.g. electrodes, can be obtained. Fast transient faradic and nonfaradic currents of electrochemical cells can be measured conveniently by a new apparatus which combines the conventional time domain spectroscopy configuration with a potentiostat. The system is applied to semiconductor electrodes in contact with an aqueous electrolyte and multiexponential relaxation spectra are observed.

An apparatus is presented which compensates automatically for the ohmic voltage drop occurring in electrochemical potentiostatic measurements, between the working electrode surface and the tip of the capillary connected to the reference electrode. The apparatus measures the potential during very short interruptions of the current. It has an input impedance of 10 T Omega and can be connected to any potentiostat or current source and adapted to the system under study. The instrument operates over large ranges of current and potential, regardless of the polarity.

Three methods are described for temperature stabilization and regulation for quenching and annealing experiments with a metal wire in a helium cryostat. All three methods use a potentiostat as a fast electronic control unit and current supply. Two methods are for temperature control for annealing an iron wire in high vacuum and for quenching the wire in liquid helium from temperatures higher than 950°C. The third method makes possible the quenching of iron wire, 1 cm above the liquid helium, from temperatures between 950 and 700°C.