Temperature sensing by Laser Reduced Graphene Oxide at different Laser Power Levels

Abstract

Laser reduced graphene oxide (LrGO) has been considered as temperature sensor and its thermal sensitivity has been studied as a function of the reduction laser power level. To do so, LrGO squares of 1 cm2 on a flexible substrate have been fabricated. We found that for the lower tested power (50 mW), both the nominal resistance (about 500 Ω) and temperature sensitivity (around -0.41 Ω/°C) are about 1.5 times higher than the values obtained with an increase in power of 10 mW. The sensor also presented a very linear response (higher than 0.99) and low variation with relative humidity (5 Ω in the RH range from 20% to 90%).