Pb single-atoms on nitrogen-doped graphene hollow spheres for electromagnetic wave absorption

Abstract

Three-dimensional carbon-based materials have attracted significant interest due to their lightweight nature; however, controlling their morphology while maintaining lightweight characteristics when combined with other materials remains a major challenge in developing materials exhibiting superior capabilities for absorbing electromagnetic waves. In this work, graphene oxide (GO) and polystyrene spheres (PS) were used as precursors to prepare hollow N-doped graphene spheres anchored with non-planar coordination of Pb single-atoms (Pb-N_x/HCS-D). The resulting Pb-N_x/HCS-D features a unique hollow structure, exhibits exceptional electromagnetic wave (EMW) absorption properties with a minimum reflection loss (RL_min) of −47.2 dB at 1.5 mm thickness and an effective absorption bandwidth (EAB) of 4.64 GHz at 1.7 mm, with a low filler content of only 10 wt%. This superior performance originates from the non-planar coordination of single Pb atoms and the interconnected hollow carbon sphere framework, synergistically improving impedance matching and enhancing dielectric loss. This study provides an effective method for synthesizing non-planar-coordination of M − single-atoms for high-performance EMW absorption.