Laser-Induced\nGraphene for Flexible and Embeddable\nGas Sensors

Abstract

Laser-induced graphene\n(LIG) has received much attention since\nit enables simple and rapid synthesis of porous graphene. This work\npresents a robust direct-write LIG-based gas sensor, which senses\ngases based on thermal conductivity, similar to a katharometer sensor.\nThe gas sensors are fabricated by lasing polyimide substrates with\na 10.6 μm CO₂ laser to synthesize LIG. This enables\nthe formation of flexible gas sensors which could be incorporated\non a variety of surfaces. High surface area and thermal conductivity\nof the LIG results in rapid response times for all studied gases.\nThe gas sensors are also embedded in cement to form a refractory composite\nmaterial. These sensors are used to determine composition of various\ngas mixtures, such as N₂ and CO₂, which are\nthe most abundant gaseous species in flue gas. Thus, LIG based embeddable\nsensors could be incorporated in composites to enable electronically\nfunctional construction materials.