极谱式柔性溶解氧智能传感器研发

Development of polarographic flexible dissolved oxygen intelligent sensors

溶解氧在维持水体生态系统和保证良好生产生活方面发挥着关键作用。随着新技术、新材料、新兴应用场景的涌现,尤其在推动渔业智能化的进程中,溶解氧的检测需要更加轻质、微小、柔软、生物相容的传感器。柔性电子与传感技术的结合为上述问题的解决提供了可能。该研究利用磁控溅射和点胶喷墨技术制备了一种具备温度测量功能的柔性溶解氧传感器并评估其线性度、灵敏度、响应时间、漂移、稳定性、机械弯曲等性能,设计相应的传感电路和智能处理系统,验证该智能传感器在养殖水体溶解氧检测中的可行性。结果表明:常温下,柔性溶解氧传感器的采集电流与溶解氧含量之间具有较好的线性关系(R^(2)为0.9945),传感器的灵敏度为-0.03μA·L/mg,响应时间为16.8 s,7 d内响应电流的最大差值为0.0195μA。柔性温度传感器在0~150℃范围内的电阻与温度具有良好的线性关系(R^(2)为0.9949),传感器的灵敏度为-2.47 kΩ/℃,响应时间为3 s,迟滞误差为2.17%,且在0~60°的弯曲范围内均保持良好的性能。所开发的智能传感器相较商用传感器在不同温度下溶解氧含量检测的最大误差小于5%,可快速准确获取待测水体的溶解氧含量和温度信息,具有良好的渔业应用前景。

Dissolved oxygen can play a key role in the production and living of aquatic ecosystems.New materials and artificial intelligence(Al)technologies can be expected to promote the process of smart fisheries in recent years.It is very necessary to equip it with light,small,soft,and biocompatible sensors.Flexible electronics and sensing technology can be combined to detect dissolved oxygen.In this study,a flexible dissolved oxygen sensor was prepared to measure the temperature function by magnetron sputtering.The inkjet was also dispensed on both sides of the flexible substrate material.A multi-layer structure of the planar electrode was then adopted for the vertical distribution of oxygen-permeable film to encapsulate the electrolyte and the planar electrode.The polarization voltage was determined for the dissolved oxygen sensor by the linear sweep voltammetry(LSV)scanning in the electrochemical workstation.The polarization time of the sensor was measured by the response experiment.In addition,a comparison was also made on the difference between the prepared and commercial electrodes.The surface morphology of dissolved oxygen and temperature sensors was characterized using optical microscopy.A series of tests were carried out on the linearity,sensitivity,response time,drift,stability,and mechanical bending properties of the sensor.Finally,the sensing circuit and intelligent processing were designed to verify the feasibility of the sensor in the detection of dissolved oxygen in aquaculture water.The experimental results showed that the optimal polarization voltage of the prepared dissolved oxygen sensor was-0.6 V and the polarization time was 42 s.There was less difference between the flexible sensor and commercial electrodes in CV scanning,indicating the better performance of ion diffusion.Both the dissolved oxygen sensor and the temperature sensor exhibited homogeneous and better surface morphology at high magnification.There was an excellent linear relationship between the collection current and the dissolved oxygen content(R2-0.9945)at room temperature.The sensitivity of the sensor was-0.03μA-L/mg,the response time was 16.8 s(the maximum difference of multiple measurements was 3.3 s),and the maximum difference within 7 days was 0.0195μA.The resistance of the flexible temperature sensor shared a better linear relationship with temperature in the range of 0-150 C and 0-30℃(R2were0.9949and 0.9976,respectively).Thesensitivity of thesensor was-2.47k2/C,theresponsetimewas3s,and the hysteresis error was 2.17%.The flexible sensor maintained better performance for the measurement of dissolved oxygen and temperature in the range of 0-60°.The maximum error of the prepared sensor was less than 5%when detecting different content of dissolved oxygen in aquaculture water at various temperatures,compared with the commercial sensor.A better temperature compensation can be obtained to rapidly and accurately detect the content of dissolved oxygen and the temperature of the water body in fishery applications.