【作者】：Li Jiang, Caileng Wang, Jing Wang, Fangmeng Liu*, Rui You, Siyuan Lv, Guoyan Zeng, Zijie Yang, Junming He, Ao Liu, Xu Ya, Peng Sun, Jie Zheng, Geyu Lu*
【题目】：Pyrochlore Ca-doped Gd2Zr2O7 solid state electrolyte type sensor coupled with ZnO sensing electrode for sensitive detection of HCHO
【关键词】：HCHO sensor, Pyrochlore solid electrolyte, Ca-doped Gd2Zr2O7, Rod-shaped ZnO
【版面信息】：Sensors & Actuators: B. Chemical 309 (2020) 127768
摘要:
Solid state electrolyte type formaldehyde (HCHO) gas sensors based on a novel pyrochlore structure Gd2Zr2O7solid electrolyte coupled with rod-shaped ZnO sensing electrode (SE) were initially designed and fabricated in this paper. The incorporation of alkaline-earth metal Ca can significantly improve sensing performance of the Gd2Zr2O7based sensors to HCHO. The response value (Delta V) of the sensors based on Gd(2-x)CaxZr2O7(x = 0, 0.02, 0.05 and 0.1) varied approximately linear with the logarithm of HCHO concentration in the range of 1-100 ppm at 600℃, with sensitivities of -25, -30, -15 and -5 mV/decade, respectively. The optimal sensor based on Gd1.98Ca0.02Zr2O7(GCZ(0.02)) exhibited the excellent sensing characteristics with maximum response value (-61.3 mV) and extremely short response time (3 s) to 100 ppm HCHO. In addition, the GCZ(0.02) sensor also showed good selectivity and stability within 20-day period of continuous high-temperature aging under high-humidity condition. Conclusively, the sensing behavior and mechanism based on mixed potential were investigated and demonstrated by the mearsurement of the polarization curves.
