A low-level acetone gas sensor based on n-type ZnO/p-type CuO composite nanostructure for the diagnosis of diabetes in dynamic situations

Today, gas sensors offer a vital method to detect and monitor the level, type, and environmental information of various gases in order to guarantee the safety of life in modern civilization. In this regard, the analysis of human breath components is one of the novel applications of analytic gas sensors to monitor the body’s metabolism function, which has received a lot of attention. The detection of acetone gas concentration in the exhaled breath is a novel promising method for the diagnosis of diabetes patients in the community health improvement plan. In the present work, a gas sensor based on zinc oxide/copper oxides composite nanostructure (ZCS) has been prepared to meet low-level acetone-sensing requirements. The XRD, FESEM, EDS, and BET analysis confirmed the presence of hexagonal wurtzite ZnO and monoclinic CuO in the composite nanostructure with nanorod morphology. The response, response/recovery time, optimum operating temperature, selectivity, and stability of the sensor were examined in dynamic situations. The results show that the ZCS can efficiently detect low-level acetone concentration. The response and response time obtained around 41.57–60.86%, and 12.6–8.1 s, respectively, toward 0.5–2 ppm target gas at the optimum operating temperature of 90 °C. The possible acetone-sensing mechanism of the ZCS through physicochemical reaction, and applying a standard thermionic emission model on I–V characteristics were discussed in detail. Investigations of temperature and frequency-dependent dielectric parameters of the ZCS were also discussed. The outstanding sensing performance of the ZCS demonstrates that it is a favorable and reliable functional acetone sensor for the monitoring of diabetes at dynamic conditions.