To realize the on-line and in situ pH detection in soilless culture, a new all-solid-stated pH sensor was presented. The pH sensor consisted of alumina ceramic (Al2O3) substrate, Sb/Sb2 O3 working electrode, Ag/AgCl reference electrode, Ag lead and pad. Sb thin film and Ag thin film were obtained by magnetron sputtering method, and then thermal annealing and Nafion modification was conducted to improve the performance of the sensor. Moreover, the influence of surface area of Sb electrode on the performance of pH sensor was investigated with the area of 4 mm2, 9 mm2, 16 mm2, 25 mm2 and 36 mm2, respectively. Through surface morphology analysis, energy spectrum analysis and electrochemical experiments, the pH sensor, which Sb electrode surface area is 16 mm2, shows excellent comprehensive performance, with high sensitivity (67.3 mV/pH), short response time (less than 3.5 s), good stability (standard deviation less than 2 mV in 700 s period), low hysteresis (less than 1.63 mV) and low drift rate (less than 1.62 mV/h). The developed sensor can be applied in pH detection in soilless culture and is promising to popularize in industrial production.

中文翻译：

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表面积对基于锑电极的全固态pH传感器的影响

为实现无土栽培中pH的在线原位检测，提出了一种新型全固态pH传感器。pH 传感器由氧化铝陶瓷 (Al2O3) 基板、Sb/Sb2 O3 工作电极、Ag/AgCl 参比电极、Ag 引线和焊盘组成。采用磁控溅射法获得Sb薄膜和Ag薄膜，然后进行热退火和Nafion改性以提高传感器的性能。此外，分别以4 mm2、9 mm2、16 mm2、25 mm2和36 mm2的面积研究了Sb电极表面积对pH传感器性能的影响。通过表面形貌分析、能谱分析和电化学实验，Sb电极表面积为16 mm2的pH传感器显示出优异的综合性能，具有高灵敏度（67.3 mV/pH），响应时间短（小于3.5 s），稳定性好（700 s周期内标准偏差小于2 mV），滞后小（小于1.63 mV），漂移率低（小于1.62 mV/h）。研制的传感器可用于无土栽培中的pH检测，有望在工业生产中推广应用。