Inexpensive Graphene Oxide Heaters Lithographed by Laser

In this paper, we present a simple and inexpensive method for the fabrication of high-performance graphene-based heaters on different large-scale substrates through the laser photothermal reduction of graphene oxide (laser-reduced graphene-oxide, LrGO). This method allows an efficient and localized high level of reduction and therefore a good electrical conductivity of the treated films. The performance of the heaters is studied in terms of steady-state temperature, power consumption, and time response for different substrates and sizes. The results show that the LrGO heaters can achieve stable steady-state temperatures higher than 200 ºC when a voltage of 15 V is applied, featuring a time constant of around 4 s and a heat transfer coefficient of ~200 ºC cm2/W. These characteristics are compared with other technologies in this field, demonstrating that the fabrication approach described in this work is competitive and promising to fabricate large-scale flexible heaters with a very fast response and high steady-state temperatures in a cost-effective way. This technology can be easily combined with other fabrication methods, such as screen printing or spray-deposition, for the manufacturing of complete sensing systems where the temperature control is required to adjust functionalities or to tune sensitivity or selectivity.This work has been supported by the Spanish Ministry of Education, Culture and Sport (MECD)/FEDER-EU through the project TEC2017-89955-P and the predoctoral grant FPU16/01451; by the European Commission through the fellowship H2020-MSCA-IF-2017-794885-SELFSENS and by Iberdrola Foundation under its 2018 Research Grant Program