Excellent microwave absorption of lamellar LaOCl/C nanocomposites with LaOCl nanoparticles embedded in carbon matrix

• Published in: Journal of alloys and compounds 2018-10, Vol.764, p.701-708
• Main Authors: Wang, Xiaolei, Bao, Xiukun, Zhou, Xinao, Shi, Guimei
• Format: Article
• Language: English
• Subjects: Carbon content; Carbonization; Dielectric; Dielectric loss; Dielectrics; Electromagnetic; Electromagnetics; Glucose; Interfacial polarization; Lamellar structure; Lanthanum chlorides; LaOCl/C; Microwave absorption; Microwave attenuation; Microwaves; Nanocomposites; Nanoparticles; Pyrolysis; Sodium chloride
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2018.06.150

Lamellar LaOCl/C nanocomposites with LaOCl nanoparticles embedded in carbon matrix have been prepared by a facile and practical approach through the pyrolysis of LaCl3·7H2O with the assistance of NaCl for the formation of LaOCl nanoparticles and sequent in situ carbonization of glucose in colloidal mixture of LaOCl and glucose. Compared with dielectric loss factors of LaOCl nanoparticles, lamellar LaOCl/C nanocomposites present enhanced multiple-dielectric resonance behaviors, which are attributed to the increase of carbon content, and thus exhibit excellent microwave absorption properties in 1–18 GHz range due to proper impedance match and improved microwave attenuation capacity. The optimal reflection loss (RL) is −32 dB at 18 GHz with a thickness of 1.5 mm, and effective bandwidth with RL below −20 dB is 14.8 GHz covering 3.2–18 GHz at the integrated thickness of 1.5–6 mm, demonstrating that lamellar LaOCl/C nanocomposites would be promising absorbents in microwave absorption field. [Display omitted] •The dielectric loss capacity of LaOCl/C nanocomposites were improved compared with that of LaOCl nanoparticles.•The optimal reflection loss (RL) is −32 dB at 18 GHz with a thickness of 1.5 mm.•The effective bandwidth with RL below −20 dB is 14.8 GHz covering 3.2–18 GHz at the integrated thickness of 1.5–6 mm.