Facile Fabrication of a Low-Cost Electrochemical Temperature Sensor

The needs of cost-effective electronic devices with easy fabrication procedure have brought the use of organic compound from metal-phthalocyanines (MPc’s) derivatives in this work for temperature sensors fabrication. Water soluble MPc’s, copper (II) phthalocyanine-tetrasulfonic acid tetrasodium salt (CuTsPc) have been used in the fabrication of electrochemical temperature sensors. The ITO-CuTsPc-ITO electrochemical cells have been prepared and characterized in the temperature range within 25–80 °C. The working principle of this temperature sensor is based on the change in the electrical parameters namely resistance and capacitance of the electrochemical cell due to the temperature variation. Fast response and recovery time were achieved including narrow hysteresis attained from a loop of temperature variation in both increase and decrease directions. The fabricated temperature sensor has shown high consistency and sensitive response towards a specific range of temperature values. Further enhancement was made by adding a small amount (1%) of titanium dioxide (TiO2) nanoparticle (25 nm) into the CuTsPc solution and has increased the sensitivity in capacitance values toward the change in temperature. It has also shown a good linearity and high stability with the change of temperature. This electrolytic nanofluid chemical cell has a great chance to be utilized as capacitive temperature sensor in electronics, energy, automation, IoT, monitoring, and health applications.