Switchable mirrors for visualization and control of hydrogen diffusion in transition metals
نویسندگان
چکیده
We show that the switchable mirror material YHx can be used both as an indicator to monitor and as an agent to control hydrogen diffusion in thin films. The applicability of the optical-indicator technique is demonstrated for VHx thin films. The diffusion coefficient is typically 10 25 cm/s at concentrations around 0.7 H/V at temperatures between 373 and 473 K. Deposition of a layer of Y on V makes it also possible to tune the effective hydrogen mobility via the V/Y thickness ratio. This can be used for investigation of hydrogen diffusion waves in laterally structured objects.
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