检测油中特征气体的铜掺杂氧化铈传感器气敏特性及吸附性能OA

Dissolved gas analysis in oil is one of the most effective methods for fault diagnosis oil-immersed transformers.Therefore,detection of characteristic gases in oil is essential to maintain the power transformer normal operation.In this paper,CeO2-based gas-sensitive materials were prepared using a one-step hydrothermal synthesis,and the successful preparation of the materials was verified by XRD,SEM and XPS characterization techniques.Based on the established gas-sensitive platform,the temperature-response characteristics,mole fraction-response characteristics,repeatability,re-sponse-recovery characteristics and selectivity of the Cu-CeO2 sensor for C2H4 were tested.It is found that the optimal operating temperature of Cu-CeO2 for C2H4 is 180 ℃,and the response value of 100×10-6 mole fraction C2H4 is 66％.The response time and recovery time are 18 s and 15 s,respectively.The sensor exhibits excellent interference resistance against C2H2,C2H6,H2,CH4,CO2,and CO gases.Furthermore,based on the first-principal calculation,the gas-sensing mechanism of the Cu-CeO2 sensor for the oil-immersed characteristic gases was analyzed by calculating the adsorption parameters,density of states,and electron density of the adsorption system.The results indicate that the Cu-CeO2 crystal surface exhibits strong chemical adsorption only for C2H4,with an adsorption energy of-1.488 eV,and the calculated re-sults are consistent with the findings from macroscopic gas-sensing experiments.Thus,the gas-sensing performance analysis and theoretical calculations in this paper provide a theoretical basis and experimental support for the development of low-power,high-sensitivity,and fast-response C2H4 sensor for the characteristic gas in oil detection.