The application of high temperature proton conductor to limiting current type hydrogen sensor

The structure and proton conduction mechanism of perovskite-type high temperature proton conductors(HTPC) are introduced. The application of HTPC to current-type and potential-type hydrogen sensor are summarized. The saturated output current vs hydrogen concentration will keep linear through dense diffusion barrier. On the basis of this working mechanism and construction three kinds of limiting current hydrogen sensors are introduced. Because the hole of sensors occlude, the performance of the aperture type and the porous layer type hydrogen sensors will be influenced through long time use. The limiting current hydrogen sensor with chemical diffusion barrier is composed of proton conductor and mixed conductor which can overcome these problems. Finally the problems and future development trend are also summarized.