Heterointerface engineering of n-heterocyclic carbene-derived n/metal dual-doped carbon materials for superior electromagnetic wave absorption

In the digital communication era, wireless devices powered by EMW have greatly advanced societal development but also intensified electromagnetic radiation pollution. Although carbon materials are considered highly promising EMW absorbers due to high electrical conductivity, excellent thermal stability, and corrosion resistance, their inherently high conductivity leads to impedance mismatch, which severely limits their application in EMW absorption. To mitigate this challenge, a dual-doping strategy incorporating heteroatomic nitrogen and metal nanoparticles has emerged as an effective strategy. This method facilitates the synergistic modulation of heterointerfaces and material composition to optimize EMW dissipation. However, conventional synthesis methods still encounter challenges in accomplishing high N-doping level and the uniform dispersion and precise size control of metal particles. In this context, developing novel preparation strategies utilizing metal-organic complexes as precursors is crucial.

A team of material scientists led by Baoliang Zhang from Northwestern Polytechnical University in Xi’an, China recently constructed NHC-derived N/metal dual-doped carbon materials (CN-X-700, X=Cu, Cu/Co and Co) with two-dimensional nanoribbon morphology. The interfacial polarization and magnetic-dielectric synergy effect caused by Cu/Co bimetallic heterointerfaces facilitate the electromagnetic response. CN-Cu/Co-700 show wide EAB of 7.11 GHz and RL_min of -62.24 dB.

The team published their review in Nano Research in August 2025.

“In this research, we present a 2D copper N-heterocyclic carbene (PIS-NHC Cu) polymer is successfully synthesized via a solvothermal method. Through a temperature-induced strategy, a series of CN-Cu-T (T=600, 700 and 800 ℃) are prepared, systematically elucidating the influence of thermal treatment on the microstructure evolution and dielectric properties of the materials. Based on the optimal carbonization temperature (700 ℃), a metal center modulation strategy is implemented to synthesize N-doped carbon materials with various heterostructures (CN-X-700, X=Cu, Cu/Co and Co). The interfacial polarization and magnetic-dielectric synergy effect caused by Cu/Co bimetallic heterointerfaces facilitate the electromagnetic response. CN-Cu/Co-700 exhibits the EAB of 7.11 GHz at a matching thickness of 3.2 mm, with the RLmin exceeding -62.24 dB. This study proposes a new paradigm for the innovation of efficient metal-anchored N-doped carbon materials,” said Baoliang Zhang, senior author of the paper, a professor in the School of Chemistry and Chemical Engineering at Northwestern Polytechnical University and vice director of Shaanxi Engineering and Research Center for Functional Polymers on Adsorption and Separation.

Other contributors include Lingfeng Tang, Haichuan Cheng, Mudasir Ahmad, Jianfeng Wu, Lei Zhang from the School of Chemistry and Chemical Engineering at Northwestern Polytechnical University, Di Lan from School of Automotive Materials, Hubei University of Automotive Technology, China.

This work was supported by the National Natural Science Foundation of China (No. 22375166, 22475170, W2433032), Natural Science Basic Research Program of Shaanxi (No. 2024JC-JCQN-44), Innovation Capability Support Program of Shaanxi Science and Technology Innovation Team Project (No. 2025RS-CXTD-024).

About the Authors

Dr. Baoliang Zhang is full professor in of School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, China. His research interests focus on methodology of organic/carbon-based porous materials synthesis and their applications in fields such as adsorption and separation, electromagnetic stealth, and electrocatalysis. Until now, he has published more than 120 SCI papers in ACS Nano, AIChE Journal and 27 national invention patents have been authorized.

About Nano Research

Nano Research is a peer-reviewed, open access, international and interdisciplinary research journal, sponsored by Tsinghua University and the Chinese Chemical Society, published by Tsinghua University Press on the platform SciOpen. It publishes original high-quality research and significant review articles on all aspects of nanoscience and nanotechnology, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials. After 18 years of development, it has become one of the most influential academic journals in the nano field. Nano Research has published more than 1,000 papers every year from 2022, with its cumulative count surpassing 7,000 articles. In 2024 InCites Journal Citation Reports, its 2024 IF is 9.0 (8.7, 5 years), and it continues to be the Q1 area among the four subject classifications. Nano Research Award, established by Nano Research together with TUP and Springer Nature in 2013, and Nano Research Young Innovators (NR45) Awards, established by Nano Research in 2018, have become international academic awards with global influence.