An In‐Situ Volumetric Method for Dynamically Measuring the Absorption of Deuterium in Palladium during Electrolysis

Abstract

A simple and reasonably accurate in situ, dynamic, volumetric method is presented for measuring the absorption of hydrogen or deuterium by palladium during the electrolysis of light-and heavy-water electrolytes. The initial rate of absorption of deuterium was found to depend upon the current density, up to a threshold value. Below the threshold, the rate of absorption is an appreciable percentage of the deuterium production rate as determined from the electrical current flow using Faraday's law. Above the threshold value, the rate of absorption is controlled by diffusion. The rate of absorption is also influenced by electrolyte pH and temperature. The equilibrium atomic loading ratio, D/Pd, was generally in the range of 0.65 to 0.85. However, in a few experiments, unexplained loading ratios of one were achieved.

Reductive Dechlorination of Hexachlorobutadiene by a Pd/Fe Microparticle Suspension in Dissolved Lactic Acid Polymers: Degradation Mechanism and Kinetics

“…ORP progressive fixation by H + /H 2 redox couple occurred later when the temperature was increased from 25 to 35 °C (Figures 3c and d). Even if lower absorption efficiency of H 2 into palladium by increasing the temperature has been reported, 59,60 this later fixation was attributed to a more important dissolution of the iron oxide shell at low pH, resulting in higher initial content in Fe(III)/Fe(II) species.…”

Hydrogen Absorption Estimation on Pd Electrodes from Electrochemical Noise Measurements in Single-Compartment Cells

“…This is the case, for example, of V-profile weld joints where the difference in chemical composition and microstructure across the thickness of the sample precludes the preparation of thin membranes or even small electrodes that could represent the bulk characteristic of those materials. Other conventional techniques like electrochemical impedance 10,11 or specific experiments 12 have been used in hydrogen absorption studies, but none of these techniques can apply to V-profile joints. As an example, in Ref.…”

The maximum hydrogen (deuterium) loading ratio in the Pd|H2O (D2O) electrochemical system

“…There is much evidence indication the existence of maximum loading ratios [7,8]. We chose one that had enough data for our analysis [8]; this is shown in Fig.…”

“…Contrary to one's expectation, the plated Pd black can accelerate hydrogen absorption but reduce the amount of hydrogen absorbing; the latter case has been verified in Ref. [7]. Some researchers recommend using smooth electrodes (r is small) in cold fusion experiments which may be due to a similar mechanism [23].…”

“…Since Fleischmann et al reported the cold fusion reactions in the electrolytically formed deuteride of palladium [4], much effort has been concentrated on the Pd|H 2 O (D 2 O) electrochemical system, especially the Pd|D 2 O electrochemical system. It has been shown that there exists a threshold of loading ratio x = 0.84 D/Pd (atom ratio) for the generation of excess heat in cold fusion and the excess heat is proportional to x [5,6], so many researchers have focused on raising x and making it reproducible [7][8][9].…”