Effect of Ethyl Cellulose on Ammonia Sensing Abilities of Gas Sensors Fabricated Using MoS2 Functional Ink for Printed Electronics Application

Abstract

Two-dimensional transition metal dichalcogenides have emerged as an excellent alternative to metal oxide and polymer-based conventional gas sensors. Liquid synthesis/processing of these materials has opened up doors for developing printed gas sensors. However, the formulation of ink and tuning its rheology require some additives. Ethyl cellulose (EC) has been consistently utilized for this purpose. In this letter, we have qualitatively assessed the role of EC addition on the performance of gas sensors based on the MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> nanosheets. In the process, we first optimized the ultrasonication time to achieve an optimal gas sensing performance. Furthermore, we optimized centrifugation time since it is an important parameter governing the printability of the ink. We further optimized the addition of EC in the solution to formulate printable ink. Ammonia sensors based on MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> solutions with and without EC were developed, and their performance has been compared at the assay of absolute response, baseline drift, response time, and recovery time. It is clearly evident that the addition of EC not only affects the device baseline current levels but also deteriorates the absolute response and minimum detection limit.