Additive Manufacturing for Rapid Prototyping of Mixed Potential Electrochemical Sensors

Abstract

Natural gas pipeline leaks are responsible methane emissions that amount to over 1.6 x 108 metric tons of CO2 equivalent and more than 2 billion dollars in losses.[1, 2] A widely deployable sensor capable of remotely monitoring pipelines to promptly detect these leaks is needed to curb their environmental and economic impact. YSZ based mixed-potential electrochemical sensors (MPES) fit this need as they are cheap and durable, allowing for wide deployment in the field. Prototyping of these sensors is enhanced by the utilization of additive manufacturing (AM).The long lead times and high start-up cost of traditional ceramic manufacturing techniques are poorly suited to prototype development of mixed potential electrochemical sensors. Recent advances in AM techniques have opened the possibility for the rapid prototyping of these sensors.[3] We report for the first time a three element mixed potential electrochemical sensor manufactured using direct write syringe extrusion. La0.87Sr0.12CrO3 (LSCO), In2-xSnxO3 (ITO), Au and Pt electrodes bridged with a porous yttria-stabilized zirconia (YSZ) solid electrolyte have been deposited on YSZ substrates. The Pt electrode and leads, as well as the porous YSZ electrolyte and YSZ substrate are deposited by direct write extrusion. The printing parameters for the printing of the YSZ substrate are optimized to achieve desired surface and bulk material characteristics. A density 60% of theoretical of the YSZ substrate is obtained after sintering at 1450 C. The sensors are evaluated for their sensitivity to methane, ethane, ammonia, nitrous oxide, and hydrogen. The sensitivity of the sensors will be compared to that of an industry standard MidIR sensor for natural gas detection.[1] A.J. Marchese, T. L. Vaugh, D. J. Zimmerle, D. M. Martinez, L. L. Williams, A. L. Robinson, A. L. Mitchell, R. Subramanian, D. S. Tkacik, J. R. Roscioli, S. C. Herndon. Science. 7204 (2018).[2] Kort, E. A.; Frankenberg, C. Costigan, K.R.; Lindenmaier, R.; Dubey, M. K; Wunch, D. Geophys. Res. Lett, 2014, 41, 19, 6898[3] Travitzky, N., Bonet, A., Dermeik, B., Fey, T., Filbert‐Demut, I., Schlier, L., Schlordt, T. and Greil, P., 2014. Additive manufacturing of ceramic‐based materials. Advanced engineering materials, 16(6), pp.729-754.Figure 1. Additively manufactured three electrode pair mixed potential electrochemical sensor. Figure 1