Xe+ ion irradiation to boost NO2 sensing characteristics of SnO2 nanowires

In this paper, pristine and Xe+ ion-irradiated sensors are studied for NO2 sensing purposes. SnO2 nanowires (NWs) were synthesized via a simple growth method and irradiated with Xe+ ions at different doses (1014, 1015, and 1016 ions/cm2). The gas sensors were fabricated after different characterizations of morphology, phase, and chemical composition. The NO2 sensing experiments revealed that there was an optimal dose (1014 ions/cm2) for which the highest response to NO2 was achieved. At 200°C, the optimal sensor had a high response of 27.32 to 10 ppm of NO2. Furthermore, the sensor demonstrated high selectivity to NO2 gas. The boosted gas response of the optimized sensor was due to the formation of n-n homojunctions between the SnO2-SnO2 NWs and the irradiation-induced formation of defects. This study confirms the usefulness of irradiation in boosting the sensing features of metal oxides.