Platinum Metals Rev., 1996, 40, (4), 180
Problems of the Palladium-Hydrogen System
An initiative by J. S. Cantrell and D. S. Sullinger produced a successful symposium on Metal-Hydrogen Systems as part of the American Chemical Society Central Section Meeting, held in Dayton, Ohio, from IOth to 1 IthJune 1996. In a sub-section of the programme, of 26 presentations, particular focus was on recent progress in hydride battery developments, and over one-third of the contributions involved hydrogen systems of palladium and palladium alloys.
Three contributions from D. K. Ross and colleagues of the University of Salford, U.K., dealt with theoretical assessments of neutron scattering measurements for palladium and its alloys, and involved discussions of trapping processes of both protium and deuterium at dislocations, and of behavioural effects of positive muons. The effects of structural defects, due to hydride phase formations and decompositions, on the tensile properties of palladium-manganese alloys were considered in a poster by A. P. Croft, Lafayette College, Easton, U.S.A.
Solutions to detailed problems involved in the desorptive removal of various impurities from palladium powders were reported by G. L. Powell, Lockheed-Martin Energy System, Oak Ridge, Tennessee and B. E. Mills, Sandia Laboratories, Livermore, California, while the involvement of thin films of palladium and palladium alloys in hydride battery developments was discussed by Y.-T. Cheng and Y. Li, General Motors Research Center, Warren, Michigan.
Various crystallographic problems associated with structural disorders produced on introducing high levels of protium, deuterium and tritium into palladium, were reported by J. S. Cantrell and T A. Breiter of Miami University, Oxford, Ohio. Two contributions from F. A. Lewis, Queen's University, Belfast, in collaboration with R. V. Bucur, University of Uppsala, Sweden, K. Kandasamy, University of Jaffna, Sri Lanka, X. Q. Tong, Southampton University and Y. Sakamoto, University of Nagasaki, Japan, dealt with sequences of structural hydride changes related to pressure-composition-temperature relationships of the Pd-H and Pd-Pt-H systems. An associated review was presented of lattice expansion strain gradients in these systems responsible for Uphill Effects observed in hydrogen diffusion processes.