Effect of Hydrogen Insertion on the Optical Properties of PD-Coated Magnesium Lanthanides
Title | Effect of Hydrogen Insertion on the Optical Properties of PD-Coated Magnesium Lanthanides |
Publication Type | Journal Article |
Year of Publication | 1998 |
Authors | Klaus von Rottkay, Michael D Rubin, Franck Michalak, Robert D Armitage, Thomas J Richardson, Jonathan L Slack, Peter A Duine |
Journal | Electrochimica Acta |
Date Published | 9/1998 |
Call Number | LBNL-42277 |
Abstract | 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. |
LBNL Report Number | LBNL-42277 |