Interaction of lead silicate glasses with hydrogen under heating

The mechanisms of formation of the surface layer of lead silicate glasses during their interaction with hydrogen under heating were studied by X-ray photoelectron spectroscopy. The thermostimulated change in the composition of an outer surface layer (with a thickness in the order of 100 Angstrom) goes in the direction of the minima in the liquidus line of the diagram of states for Pb0-SiO2, The reduction process follows the scheme [PbO3](delta-) --> Pb-mod - O --> [PbP](ion)--> Pb-o, where [PbO3](delta-) is the network-forming lead (glass former), Pb-mod the modifier lead, [PbO](ion) the intermediate lead-oxygen compound with a more ionic character of the Pb-O bond. (C) 2002 Published by Elsevier Science Ltd on behalf of the International Association for Hydrogen Energy.