Ceramic Additive Manufacturing for the Rapid Prototyping of Mixed Potential Electrochemical Sensors

Abstract

Ceramic electrochemical sensors play a major role in chemical analysis of gas species, and mixed potential sensors are attractive for their robustness in harsh environments such as automotive exhaust gases. A major challenge for rapid prototyping of ceramic chemical sensors is the high cost, high material waste, and low geometric flexibility of traditional screen printing and tape casting methods. While these two methods are suitable for mass production of thousands to millions of devices, they tend to be cost prohibitive for small scale rapid prototyping applications. Additive manufacturing techniques enable greater flexibility in working with small batches of materials, customized geometry, and shorter turnaround time.We will discuss efforts in the additive manufacturing of ceramic mixed potential sensors by extrusion of ceramic and conductor pastes onto zirconia laminates. [1] We evaluated the sensor performance to various test gases at the 100 PPM level including NOX, NH3, and C3H8, observing responses on the order of mV/100 ppm. Electrochemical techniques were employed to probe the effects of porosity on sensor response and evaluate the reproducibility of AM techniques. Finally, we will report on the printing of a ceramic gas sensor by extrusion of a ceramic paste to form the substrate instead of using a laminate substrate to demonstrate a complete device can be produced by AM techniques only.[1] Tsui, L.K.; Benavidez, A.; Evans, L.; Garzon, F.G. Prog. Additive Manuf. 2019, 4, 1, 13-21