Abstract
CaCu3Ti4O12(CCTO)ceramic nanocomposites incorporating graphene-carbon black(GRCB)fillers were fabricated by spark plasma sintering process.The per-colative effects of conductive GRCB fillers on dielectric response of GRCB/CCTO ternary metacomposites were systematically investigated.The weakly real permittivity(ε')-negative response(ε'～-1 × 102)was achieved which originated from weakly low-frequency plasmonic state of free carriers within constructed GRCB networks.With enhancing three-dimensional GRCB network,the plasma frequency of metacomposites increased while the damping factor decreased.Herein,the e'-negative values of metacomposites were tuned from-102 to-104 orders of magnitude and ε'-near-zero(ENZ)frequencies from～142 to～340 MHz which substantially benefited from the moderate carrier concentration of GRCB dual fillers.The Drude model and equivalent circuit models were adopted to demonstrate dielectric and electrical character-istics.The obtained metacomposites show strong EM shielding effect along with enhanced plasmonic oscillation and even better achieving perfect EM shielding effect in ENZ media.This work achieves the tunable ε'-negative andε'-near-zero response and more importantly clarifies its regulation mechanism in ceramic-based ternary metacom-posites,which opens up the possibility of designing high-performance EM shielding materials based on metacom-posites.
基金项目
国家自然科学基金(52205593)
Fund of Natural Science Special(Special Post)Research Foundation of Guizhou University(2023-032)
Platform of Science and Technology and Talent Team Plan of Guizhou Province(GCC[2023]007)
NETL
NSTL
万方数据