Massive enhancement in sensitivity of mixed potential sensors towards methane and natural gas through magnesia stabilized zirconia low ionic conductivity substrate

Monitoring of methane leaks from natural gas (NG) sources during production and transport is vital to combating the threat of greenhouse gases to the global climate. An additive manufacturing route was developed for the printing of a CTE matched, low reactivity and low ionic conductivity magnesia stabilized zirconia (MSZ) substrate for production of a four-electrode (indium tin oxide, lanthanum strontium chromite, and Au sensing electrodes measured against a Pt negative electrode) same-side planar mixed potential electrochemical sensor (MPES) with porous 3 mol% YSZ as electrolyte. The MSZ substrate based MPES achieves a 40 ppm limit of detection for methane in a simulated natural gas mix. Additionally, a 20 times enhanced response in the ITO vs. Pt signal over sensors using yttria-stabilized zirconia (YSZ) substrates at 100 ppm CH4 in simulated natural gas is observed. This research illustrates the importance of a CTE matched, low reactivity, low conductivity substrate for optimal performance of same-side planar MPES devices for NG leak detection while allowing for application of high temperature co-fired ceramic technologies.

Automated summary

Monitoring methane leaks from NG sources is crucial for combating greenhouse gas emissions. This study developed an additive manufacturing method for printing a CTE matched, low reactivity, and low ionic conductivity MSZ substrate for the production of a four-electrode MPES. The MPES with the MSZ substrate showed a 20 times enhanced response in the ITO vs. Pt signal compared to sensors using YSZ substrates at 100 ppm CH4 in simulated natural gas, highlighting the importance of the substrate for optimal performance.