(A) study on electrolysis of heavy water and interaction of hydrogen with lattice defects in palladium electrodes

Abstract

Excess tritium analysis was performed to verify whether or not cold fusion occurs during electrolysis of heavy water in the current density range of 83~600 mA/㎠ for a period of 24~48 hours with use of palladium electrodes of 7 different processing treatments and geometries. The extent of recombination of $D_2$ and $O_2$ gases in the electrolytic cell that must be taken account in the calculation of accurate enthalpy values was also examined. The behavior and interaction of hydrogen atoms with defects in Pd electrodes were examined using the Sieverts gas charging and the positron annihilation(PA) method. Tritium enrichment was observed during electrolysis but excess tritium that could be considered as a by-product of cold fusion was not detected under the present electrolysis conditions. The extent of recombination of $D_2$ and $O_2$ gases was 32%. Hence the excess heat could be generated due to exothermic reaction of recombination but not due to nuclear fusion. Lifetime results from the PA measurements of the Pd electrodes indicated that hydrogen atoms could be trapped at dislocations and vacancies in the electrodes and that dislocations were slightly more perferred sites than vacancies. R parameters from the PA measurements of the hydrogen-charged Pd electrodes indicated that the formation of hrdrides was accompanied by generation of mostly dislocations. Doppler broadening results of the Pd electrodes indicated that lattice defect sites where positrons were trapped were increasing followed by decreasing repetitiously as electrolysis continued. PA measurements of the cold-rolled Pd and the Pd hydride specimens annealed isochronally indicated that microvoid-type defects existed in the hydrogen-charged electrode specimen.