The impact of different flexible substrates on the photothermal reduction quality of graphene oxide†

In this work, we demonstrate the impact of the photothermal reduction quality of graphene oxide (GO), which is affected by the material composition, roughness, and thermal properties of the membrane substrates. We show high efficiency reduced graphene oxide (rGO) conversion by applying a 405 nm pulsed laser in ambient conditions onto different flexible substrates. Three filter membranes, such as nylon, cellulose acetate, and nitrocellulose, are used as rGO thin film substrates, achieving sheet resistance of 51 ± 2, 58 ± 3, and 620 ± 40 Ω sq⁻¹, respectively, which has been the lowest resistance reported in ambient conditions. Finally, we demonstrate that such flexible materials can be applied as temperature sensors ranging from 35 °C to 100 °C. The best sensitivity is achieved using nylon membranes, showing a smoother rGO surface and lower defect density.