Methane sensitivity of Fe-doped SnO2 thick films

It has been observed that iron as a solid solution in SnO2 remains in Fe3+ state and acts as a p-type dopant. This results in an appreciable increase in the resistance of iron doped tin dioxide thick films, although above 350 °C, such increase in resistance is not significant with respect to that of pure tin dioxide. Methane sensitivity of such iron doped tin dioxide films showed marginally inferior behaviour to that of pure tin dioxide. However, above 350 °C, in contrast to pure tin dioxide, the methane sensitivity of iron doped tin dioxide films has been found to be very poor.