Reduced graphene oxide/MnFe2O4 nanocomposite papers for fast electrical heating and microwave absorption

Reduced graphene oxide (RGO) and magnetic metal oxide composite papers are high needed in microwave absorption, shielding and rapid electrical heating. Herein, a self-assembled multifunctional RGO/MnFe2O4 paper is effectively prepared by a simple method of solution casting and thermal reduction for electromagnetic shielding, microwave absorption, temperature-sensing, electrothermal de-icing. A fast electrical heating is achieved, a saturation temperature of 100.2 °C can be provided within 15 s at a constant current of 0.35 A. In addition, the composite paper under a thermal reduction temperature of 800 °C gives an electromagnetic shielding efficiency (SE) value of 29 dB at X-band and a reflection loss (RL) of 43.2 dB at 14.1 GHz with a thickness of 3 mm and an effective bandwidth (RL < −10 dB) from 10.5 to 16.2 GHz. More, the contact resistance between the graphene-based paper and electrode is decoupled based on the equivalent circuit model, which is greatly contribute to its higher electrothermal and other electrical performance. And the contact resistance is 19.18 Ω, which accounts for 15% of the total resistance of the RGO/MnFe2O4 composite. This RGO/MnFe2O4 paper can offer great potential for fast electrical heater, high performance microwave absorbing and shielding materials.