%0 Journal Article
%A Klaus von Rottkay
%A Michael D Rubin
%A Franck Michalak
%A Robert D Armitage
%A Thomas J Richardson
%A Jonathan L Slack
%A Peter A Duine
%B Electrochimica Acta
%C London, U.K.
%D 1998
%G eng
%L LBNL-42277
%T Effect of Hydrogen Insertion on the Optical Properties of PD-Coated Magnesium Lanthanides
%1 <p>Windows and Daylighting Group</p>
%2 LBNL-42277
%8 09/1998
%X <p>Metallic magnesium lanthanide thin films upon insertion of hydrogen transform to a highly transparent hydride phase. With a Pd overlayer, the transformation can be produced either by electrochemical insertion of hydrogen or by exposing the film to hydrogen gas. Unlike amorphous oxide electrochromics, the transformation is accompanied by a large change in visible reflectance (about 50%). The optical switching effect in these materials is investigated in terms of changes in the complex refractive index as determined by variable-angle spectroscopic ellipsometric and normal-incidence radiometric measurements over the solar spectrum. Furthermore the optical effect of converting the Pd caplayer to Pd-H was determined. It is shown that the pd layer limits the visible transmittance of the hyrdrided stack to about 35-40%. Whereas the extinction coefficient of the dehydrided LnMg-layers at 550 nm is between 2.2 and 3.1, it is as low as 10-4 in the transparent state.</p>