The project will deal with a complex research of gas sensing properties of a chemoresistive device which employs single-1D nanostructure. Such device will be prepared by fixing the 1D nanostructured "basic" oxide decorated with either metal catalyst or another oxide (modifying the charge-transport phenomena in the 1D nanostructure) on a chip platform with a possibility of self-heating. In local scale, the surface physico-chemical processes will be studied in-situ by Near- Atmosphere Pressure X-ray Photoemission Spectroscopy (NAP-XPS) or other spectroscopy techniques (e.g., Raman, FTIR, UPS, SRPES) to better understand the sensing mechanism. Simultaneously, the "integral" parameters of the device (measuring current, operating temperature generated by self-heating) will be monitored. Finally, the results of both local-scale and "integral" studies will be put into context with the performance parameters of chemoresistive device (sensitivity, detection limit, selectivity, heating/measuring current, response time, recovery time).