Renewable antimony-based pH sensor

Metal-based pH sensor has wide applications in industrial monitoring, soil environment, marine safety, and other fields. In this study, we proposed to renew the antimony-based sensor by physical polishing and electro-chemical cathode reduction. Compared with before polishing, the pH response sensitivity after polishing increased from 0.034 V/pH to 0.042 V/pH, electrochemical cathode reduction renewed the pH response sen-sitivity improved from 0.018 V/pH to 0.032 V/pH (10 min) and 0.043 V/pH (30 min). The reasons for the dete-rioration of the pH response performance of the antimony-based sensor were analyzed by SEM, EDS, and XRD, and the renewable mechanisms of the sensor were proposed. The renewable effect of electrochemical cathode reduction on the degradation of sensor accuracy was evaluated for long-term monitoring. It is expected to real-ize remote online renewal of sensors under on-site unattended conditions, to reduce operation and mainte-nance costs of the sensor. These results provide solutions for the repeated regeneration of metal-based pH sensors which were degraded in performance and have significance for promoting the development and wide applications of renewable pH sensors.

Automated summary

In this study, the renewal methods of antimony-based sensors were proposed by physical polishing and electro-chemical cathode reduction. The pH response sensitivity of the sensor increased after polishing, and further improvement was achieved through electro-chemical cathode reduction. The reasons for the sensor's deterioration and renewable mechanisms were analyzed, and the renewable effect of electro-chemical cathode reduction was evaluated for long-term monitoring.