Transparent Pd Wire Network-Based Areal Hydrogen Sensor with Inherent Joule Heater

Abstract

A high degree of transparency in devices is considered highly desirable for futuristic technology. This demands that both the active material and the electrodes are made of transparent materials. In this work, a transparent Pd wire network (similar to 1 cm(2)), fabricated using crackle lithography technique with sheet resistance and transmittance of similar to 200 Ohm per square and similar to 80%, respectively, serves multiple roles; besides being an electrode, it acts as an active material for H-2 sensing as well as an in-built electrothermal heater. The sensor works over a wide range of hydrogen (H2) concentration down to 0.02% with a response time of similar to 41 s, which could be improved to similar to 13 s by in situ Joule heating to similar to 75 degrees C. Importantly, the device has the potential of scale-up to a window size transparent panel and to be flexible when desired.