Palladium Cathode Research Articles

Bubble-free electrophoretic deposition of aqueous zirconia suspensions with hydroquinone

Electrophoretic deposition (EPD) is a colloidal processing technique for ceramics in which charged particles move toward, and are deposited upon an electrode with the opposite charge [1–3]. The EPD technique has many advantages, such as the fast, easy, and uniform formation of complex shapes, good control of deposition thickness, high green density. This method has been used to fabricate thin films, multilayered composites, functional materials, etc. Non-aqueous suspensions are usually preferred for the EPD process to prevent electrolysis of the solvent and to obtain bubble-free deposition. On the other hand, an aqueous shaping system is advantageous from the viewpoints of ecology, safety, and cost. Water is decomposed into hydrogen and oxygen when a DC current is passed through an aqueous medium. There have been some reports of the fabrication of a bubble-free deposit from aqueous suspension [4, 5]. Recently, Uchikoshi et al., investigated the EPD characteristics of positively charged particles onto various cathodic substrates using aqueous alumina suspensions [5]. They found that no macro pores were formed in the EPD deposit on a palladium cathode, and that the green density and sintered properties of the deposits were the same as those produced by the slip casting process. It is well known that hydroquinone (HQ) is readily oxidized to quinone (Q) at high pH in alkaline solution [6]:

Generation of Nuclear Tracks during Electrolysis

We show that energetic charged particles are produced during electrolysis of a D2O solution of Li2SO4 in a cell with a platinum anode and a palladium cathode. CR-39 plastic detectors, designed for recording alpha particles from radon decay, were immersed in the electrolyte during electrolysis. They recorded significantly larger numbers of energetic particle tracks than were recorded by control detectors not subject to electrolysis. Statistical analysis shows only a 3×10-6 probability that the electrolysis tracks and the control tracks could have arisen from a common population. We conclude that there is a causal relationship between electrolysis and the production of energetic charged particles. Because track formation requires particle energies substantially greater than thermal or electrochemical energies it seems inescapable that a nuclear reaction was responsible.

Search for 3He and 4He in Arata-Style Palladium Cathodes I: A Negative Result

The 3He and 4He concentrations in 2- to 6-mg samples of palladium-black from the interior of Arata-style cathodes were investigated using a tungsten wire furnace on-line to an ultrahigh sensitivity static mass spectrometer. The detection limit of the mass spectrometer was ~104 atoms 3He and 108 atoms 4He, and the mass resolution of 1 part in 620 was sufficient to cleanly resolve 3He from H3 and HD. Three specimens of palladium-black (A, B, and C) were from hollow Pd cathodes that had generated excess heat in D2O electrolysis experiments carried out by Arata and Zhang in their laboratory. One specimen of Pd-black (D) had not been used in any electrolysis experiment. A total of twelve samples, three from each specimen, were analyzed. The 3He and 4He concentrations were variable as if due to sample inhomogeneity. Two samples (C-1 and B-1) showed apparent 4He of 4.4 × 109 atoms/mg and 6.6 × 109 atoms/mg, respectively, and three (A-3, B-2, and D-3) showed excess 3He from 77 to 1096 × 103 atoms/mg relative to the atmospheric 3He/4He ratio. Seven samples showed no apparent excess of 3He or 4He. Five samples of the aluminum foil used to wrap Pd-black samples were also analyzed and gave mean values of 13 ± 18 × 103 atoms/mg and 1.50 ± 0.66 × 109 atoms/mg for 3He and 4He, respectively. The values for Al and Pd-black are comparable to the 1978 results of Mamyrin, Khabarin, and Yudenich, who examined helium isotopes in many ordinary metals and other materials including Al and Pd. At present, there is no evidence for the very much larger concentrations (1016 to 1017 atoms/mg) of 3He and 4He that Arata and Zhang claim to have detected in similar specimens of Pd-black from Pd cathodes subjected to D2O electrolysis.

Are tetraalkylammonium cations inserted into palladium cathodes? Formation of new palladium phases involving tetraalkylammonium halides

The cathodic behaviour of a wide variety of tetraalkylammonium halides was studied at a polished palladium cathode in aprotic dimethylformamide. Coulometric and electrochemical quartz crystal microbalance analyses demonstrated the formation of clusters whose stoichiometry was determined, attesting to the reversible insertion of cations and anions belonging to the electrolyte into the metallic bulk.

The cathodic insertion of tetraalkylammonium iodides into palladium

The cathodic behavior of tetraalkylammonium iodides was studied at a polished palladium cathode in aprotic dimethylformamide (DMF). Coulometric and electrochemical quartz crystal microbalance analyses allowed to show the formation of phases, the stoichiometry of which was fully determined. The reversible insertion of tetraalkylammonium cations as well as the electrolyte into palladium was demonstrated.

SEM and EDS Characterization of Palladium Cathodes After Electrolysis in Light and Heavy Water

Abstract Studies of Pd foil cathodes have indicated that when electrolyzed for long times in electrolytes containing both deuterium and hydrogen ions along with sulfuric acid, the cathodes undergo compositional, topographical, evolutionary, and isotopic changes. The results reported here describe the changes which are produced in Pd cathodes after only a few minutes of electrolysis. In June 1993 a cold-rolled, Pd (AESAR lot #12E06) cathode of 40μm thickness was submerged at one end into an electrolyte containing 20 ml D2O and 3.5 ml H2SO4 and electrolyzed for six minutes at about 0.6 A/cm2 and 3.65 V. An identical Pd cathode (cut from the same strip) was submerged at one end into an electrolyte containing 20 ml H2O and 3.5 H2SO4 and electrolyzed for six minutes using 0.6 A/cm2 and 4.11 V. A Pt foil acted as the anode in each case. The two cells were connected in series. An ionic current flowed between the electrodes for each system as the voltages were applied.

Confirmation of The Changes of Isotopic Distribution for The Elements on Palladium Cathode after Strong Electrolysis in D2O Solution

Many elements on Pd electrode were confirmed by several analytic methods; reaction products with the mass number up to 208 are deposited on palladium cathodes, which were subjected to electrolysis in a heavy water solutionat high pressure, temperature, and current density for prolonged time. Thesemasses were composed of many elements ranged from hydrogen to lead.Extraordinary observations were the changes of their isotopic distributions inthe produced elements; these were radically different from the natural ones.For example, natural chromium is 4.3% Cr 50, 84% Cr 52, 9.5% Cr 53 and 2.4% Cr 54. But the Chromium found on the Pd surface was 14% Cr 50, 51% Cr 52, 2.4% Cr 53 and 11% Cr 54. Natural Isotopic distribution varies by less than0.003% for Cr. Essentially the same phenomenon was confirmed eight timeswith high reproducibility at high cathodic current density, above 0.2A /cm2.All the possibilities of contamination had been carefully eliminated by severalpretreatments for the sample and electrolysis system. It means that a nuclearreaction had taken place during the electrochemical treatment. It is indicating the role of new interactions discovered in the framework of a generalization of the usual quantum mechanics. Evidently such new interactions, due tothe mutual overlap of wavepackets, should explain the new phenomenologiesthat are experimentally observed in this study.

Effect of Boron for The Heat Production during The Heavy Water Electrolysis using Palladium Cathode

The heat balance during the electrolysis using B controlled Pd cathodes in1M LiOD heavy water solution has been measured using the flow calorimetersystem. We used two systems ; one is the high accurate system where theexperimental error was reduced to ±1.5%, the other is the high heat recoverysystem. The excess heat was observed for 6 experiments out of 14 for B controlled specimen. Most of the excess heat was very small except one examplewhere we observed a heat burst of 1.8W using Pd that contained 500ppm B.

Present Status Of Cold Fusion Experiment at KEK

Since spring of 1989 we have attempted to confirm the so-called cold fusion phenomena by detecting excess heat and various nuclear products, usingopen type electrolysis cells. A variety of cells containing Pd (cathode)/0.1M LiOD/Pt (anode) were examined, but recently efforts have been concentratedon dewar type cells containing a small palladium cathode, about 2mm∅×7mm in size. Until now a burst-like heat release, equivalent to 110% of theinput electric power, was observed in one cell, with neither increase of neutronemission nor that of tritium concentrations. Helium was observed, but nodecisive conclusion could be drawn due to incompleteness of the then used detecting system. In another experiment an abnormal increase of neutron emission, about 3.8σ above the background level, was observed with neither coincidentalheat burst nor tritium anomalies. It lasted for 9 hours and the emission ratethat amounts to 27.2±11.2 neutrons s-1 was 700 times as much as the background level. It happened also only once, which makes the possibility of thesystem error negligible and paradoxically supports its reality. In the otherexperiment abnormal emission of the low energy (below 20 keV) X-ray hasbeen detected during the D+ charging period, indicating some type of nuclearphenomena may be happening in the cell. Further studies as well as reproductions of the anomalies are becoming highly essential to understand totallythese abnormal phenomena.

Material characteristics and behaviour of highly deuterium loaded palladium by electrolysis

Studies on several kinds of palladium cathodes have been conducted in electrochemical cells using LiOD/D 2O electrolyte to determine necessary and sufficient conditions for attaining high deuterium loading. Comparative observations of the microstructure and analysis of surface impurities have been carried out on palladium specimens with various pre-electrolysis treatments and post electrolysis. From the observations and analysis of various processed and treated Pd specimens, the material characteristics of a Pd cathode achieving high loading ratios (D/Pd>0.85) are discussed.

Density gradient isoelectric focusing of proteins in artificial pH gradients made up of binary mixtures of amphoteric buffers.

A density gradient electrophoresis apparatus made of Perspex (7 cm, O 2.2 cm) with a circular platinum anode and a palladium cathode was used for the separation of proteins in free liquid. Following a concept developed by M. Bier et al. (Electrophoresis 1993, 14, 1011-1018), mixtures of two suitable amphoteric buffers I and II provide for media with a fixed and electrophoretically stable pH or were used for the generation of preformed (electrophoretically stable) pH gradients covering about 1 pH unit. Amphoters I and II are considered suitable if there is overlap between (pK(1,1)-1-2) and the pK(2,II)+1+2) region. 3-(N-Morpholino)propanesulfonic acid (MOPS) and gamma-amino-n-butyric acid (GABA) were used as an example. Two approaches were followed: (i) rate-zonal separation of test proteins in a pH window, formed by a fixed ratio of MOPS/GABA. (ii) Isoelectric focusing in a shallow preformed pH gradient, made up of inverse reciprocal linear gradients of MOPS and GABA. At isopH, test proteins (bovine serum albumin, cytochrome c, ferritin, hemoglobin, lactoglobulin, myoglobin, and transferrin) were rate-zonally separated within a short time. Even the separation of the A and B forms of lactoglobulin was feasible at isopH. The glycoforms of transferrin were separated and enriched on a pH 5.2-6.1 pH gradient, indicating that pH differences of about 0.01 still permit resolution. Contrary to the ill-defined Ampholines, the cost of these well-defined amphoters is low.

Kinetics of the deuterium and hydrogen evolution reactions at palladium in alkaline solution

The kinetics of the deuterium evolution reaction (DER) at palladium in alkaline solution were investigated by measuring the overpotential decay transients arising from interruption of the polarising current. It was found that the overpotential η could be time-resolved into two separate components. The initial component η 1 arises from the Volmer reaction, while the longer-lived component η 2 is attributed to the Tafel reaction. The Volmer-Tafel mechanism was also confirmed by examining the dependence of η 2 on η, although there were some indications that, at high overpotentials, the Heyrovsky reaction is also involved. Studies of the hydrogen evolution reaction (HER) at palladium were also consistent with a Volmer-Tafel process. The rates of the Volmer and Tafel reactions were found to be higher for the HER than the DER, in agreement with known electrolytic H/D separation factors. Measurements of η 2 were used to estimate the stoichiometry of the deuterated palladium cathode using the concept of equivalent D 2 pressure. The D/Pd loading ratios were found to increase with current density, reaching values of between 0.78 and 0.82 at 50 m A cm −2.

Reproducible D/Pd Ratio >1 and Excess Heat Correlation by 1-µs-Pulse, High-Current Electrolysis

AbstractA high-current (up to 100 A), short-pulse (1-µs duration) electrolysis technique is presented that permits high loading (D/Pd up to 1.2) of deuterium in palladium cathodes. Several different cold-worked palladium plates were used as cathodes, and some underwent surface treatments (oxidation or addition of intermetallic compounds). The surface-treated plates showed atypical deuterium absorption dynamics, and the D/Pd loading ratio exceeded 1. Moreover, during initial loading, these cathodes showed anomalous excess heat (up to 80%) far greater than the absorption enthalpy. The pure palladium surface plates did not show this effect.

Electrochemical removal of NO and CH4 in the presence of excess O2, H2O and CO2 using Sm2O3-doped CeO2 as a solid electrolyte

Electrochemical removal of NO and CH4 from a gas stream containing excess O2, H2O and CO2 has been carried out between 400 and 800 °C using a single-compartment reactor, which is constructed from CeO2-based solid electrolyte with two palladium electrodes. At all temperatures studied, both NO and CH4 were decomposed by applying a direct current to the reactor. NO was decomposed to N2 in two different ways depending on the applied current. At low currents, NO was electrolysed together with O2 at the palladium cathode; and, at high currents, NO was catalytically reduced over the palladium surface free from adsorbed oxygen. By investigating the influences of the concentration of NO, H2O, CO2, CH4 or C3H8 contained in the reactant gas to these two decompositions, their mechanisms are discussed in detail.

An Investigation of Reports of Fusion Reactions Occurring at the Cathode in Glow Discharges

Recent reports of deuteron-deuteron (d-d) neutrons resulting from nuclear reactions in or at the palladium cathode of a deuterium glow discharge were investigated. The equipment, techniques, and experimental procedures are discussed in detail, as well as various possible mechanisms to produce such reactions. The results of this investigation do not confirm the presence of d-d reactions. 15 refs., 9 figs.

High resolution density gradient electrophoresis of cellular organelles.

A density gradient electrophoresis apparatus made of Perspex was constructed, with a separation column (7 x 2.2 cm) containing a 0-5% linear Ficoll gradient. The useful separation path is 6 cm. A specially designed gradient mixer is described which fits over the application cone. This cone permits precise gradient and sample introduction as well as undisturbed fractionation after electrophoresis. A bottom circular palladium cathode is separated hydrodynamically but not electrically from the density gradient by a cellophane membrane, merely secured by an O-ring. The top circular platinum anode allows for upward electrophoresis (80-100 min at 10 mA). The markedly higher resolution of subcellular organelles was compared with separations obtained earlier with a small, but much more difficult to fabricate, prototype. Moreover, ease of manipulation was greatly improved. A wide separation distance was obtained between plasma membrane, endoplasmatic reticulum as well as between two populations of lysosomes. Even early, middle, and late endosomes could be separated with high resolution. Soluble isoenzymes could be separated as well and were far away from the vesicle-enclosed enzymes.

Analysis of Deformed Palladium Cathodes Resulting from Heavy Water Electrolysis

Earlier experiments suggested that large differences in heat release between the two sides of a palladium electrode coated with gold on one side and manganese oxide on the other cause observed electrode deformation with high-pressure D{sub 2} gas loading in an electrolysis-like cell. Similar experiments were repeated using heavy water electrolysis. Palladium/titanium coatings on one side and gold coating on the other were made for the preparation of the palladium electrodes. Biaxial bending, partial discoloration, and microcracks of palladium electrodes were observed after 18 days of electrolysis. Analysis of the deformed palladium cathodes was performed. It was discovered that to convert this configuration to a practical energy-producing cell, a coating technique must be found to reduce outward diffusion of deuterium, i.e., to maintain a high D/Pd ratio over longer periods of time. 33 refs., 7 figs., 1 tab.

Precision calorimetric studies of H2O electrolysis

Calorimetric studies were undertaken of the heat, observed during the electrolysis of H2O in normal open and closed cell as well, employing palladium cathode. A difference in heat observed during the process between opened and closed system was found. Heat generated under different conditions was presented as a function of the working current density or voltage. Such results were briefly discussed according to general thermodynamics and electrochemistry.

In situ measurement of the deuterium (hydrogen) charging of a palladium electrode during electrolysis by energy dispersive x-ray diffraction

A method to determine the concentration of deuterium inside a palladium cathode during the electrolysis of LiOD–heavy water solution is described. This method is based on the measurement of the host metal lattice parameter which is linearly related to the concentration in a wide range. A hard-x-ray beam which is able to cross two glass walls and few centimeters of water solutions without suffering a strong attenuation has been used. The measurement of the lattice parameter is performed in situ, during the electrolysis, by using energy dispersive x-ray diffraction. The sample volume illuminated by the x-ray beam is limited to a small region close to the surface and depends on the incident photon energy. In principle, this allows one to study the dynamics of the charging process and to determine the concentration profile in the range from few up to tens of micrometers. The deuterium concentration, determined by this method, was then checked by degassing the cathode in a known volume and was always found in a very good agreement, showing that the charging was uniform for the whole sample.

Separation Factors for Hydrogen Isotopes on Nickel and Platinum during Electrolysis

When a nickel cathode is used during electrolysis, the separation factor {gamma} of D{sub 2}O/T{sub 2}O is measured and found to be 2. When a platinum cathode is used, the value of {gamma} is found to also be 2. This value is the same as the value that was measured and reported in an earlier paper that dealt with the use of a palladium cathode. A mathematical model that predicts the tritium concentration in the electrolysis cell finds the predictions to be in agreement with the measured values of tritium concentration in the cell. Excess tritium concentration is observed in the recombined off-gases in the case of the nickel cathode. 3 refs., 2 figs., 2 tabs.