▎ 摘　　要

The electromagnetic shielding efficiency of a given material can be quantified as the sum of three contributions: reflection, absorption, and multiple reflections, which under certain conditions can be reduced to the first two, which are the main shielding processes decisive for its further application. A simple process to prepare nitrogen-doped graphene aerogels followed by subsequent thermal treatments is proposed to adapt and control the shielding mechanisms that take place to the possible requirements of the system. Nitrogen-doped aerogels are prepared by the addition of urea in the hydrothermal synthesis and subsequent heat treatments at 500 and 1000 degrees C. Reflection/absorption power ratio values of unity down to values as low as 0.2 are obtained. This study represents an advance in electromagnetic shielding materials and the adaptation of these to the needs of different applications, reducing the traditional negative environmental impact of these devices.