Gas and humidity analyses in gasochromic processes of switchable mirrors

Abstract The gasochromic processes of switchable mirrors based on a Mg–Y alloy were studied by measuring the change in volume concentration (vol%) of H2 in the air gaps of a mirrored cell using a residual gas analyzer. The change in the optical transmittance of the mirrors and the relative humidity in the gaps during the processes were measured simultaneously. An important factor for developing a practical switching system, which helps realize a fully hydrogenated state without water condensation, is to control the vol% of H2 in the air gap to be 1.0%.