I research gas sensors based on metal oxide semiconductors. I need the gas sensor element without gas-sensing materials to deposit materials synthesized by our team to fabricate the device.
Are you saying you need to get a gas sensor with no sensitization molecules pre-deposited? I'm not away of such a product, but you could contact the manufacturer to see if they could make you one specially. Or if that is too expensive you may be able to etch those chemicals off of the sensor to return it to its initial state.