A novel cellulose-derived graphite carbon with abundant defects for excellent environmental adaptability and superior wideband microwave absorbents

Abstract

It is still an enormous challenge to regulate microstructure of pure carbonaceous electromagnetic (EM) wave absorbents in order to gain superior wideband microwave absorption (MA) with environmentally adaptive ability. Herein, the novel pure cellulose-derived graphite carbon materials (CGC) with abundant defects were fabricated via the self-assembly strategy combined with simple carbonization for the first time. The EM and MA performance of as-prepared CGC with different carbonization temperatures were studied in detail. The minimum reflection loss of CGC was up to −46.2 dB (over 99.99% MA) at only 1.42 mm, and the maximum effective absorption bandwidth (EABmax, RL < −10 dB) was as wide as 6.32 GHz. The greatly improved MA of pure carbon materials outperformed those of many previously reported carbon-based composite absorbents with tedious preparation process. The excellent MA property was attributed to the optimal synergy of good impedance matching and satisfactory EM attenuation capability. Besides, the CGC still retains a strong and broadband MA ability in the simulated real harsh environmental conditions (acid rain/alkaline solution, salt spray and strong UV exposure). Hence, the CGC is believed to be a very promising candidate as high-efficiency EM wave absorbents with wide frequency and excellent environmental adaptability for practical application.

Keywords

• Graphitic carbon
• Cellulose
• Microwave absorption
• Environment adaptability
• Polarization
• Impedance matching