TY - JOUR

T1 - CVD–Grown CNTs on metallized fly ash cenospheres as tunable microwave–functional fillers

AU - Nuriakhmetov, Zaur N.

AU - Nerushev, Oleg A.

AU - Betke, Igor A.

AU - Chernousov, Yuri D.

AU - Smovzh, Dmitry V.

AU - Komarov, Andrey G.

AU - Savichev, Vladimir I.

N1 - This work was supported by the Institute of Thermophysics SB RAS (Project No 122022800487–2) for sample preparation, and the Institute of Chemical Kinetics and Combustion SB RAS (Project No FWGF-2021–0003) for measurements.

PY - 2026/3

Y1 - 2026/3

N2 - A hierarchical filler was synthesized by growing multi-walled carbon nanotubes (MWCNTs) on aluminosilicate fly ash cenospheres (FACs). The process involved depositing a uniform ferromagnetic Fe catalyst layer (55 nm) via magnetron sputtering, followed by the chemical vapor deposition of a dense MWCNT array (50–60 nm diameter). Composite samples containing 20 wt.% of this filler in a polyurethane matrix were prepared. Their microwave properties were characterized by measuring the scattering parameters (S-parameters) over the 1–13 GHz frequency range. Subsequently, the complex permittivity and permeability were extracted from the S-parameter data using the Nicolson–Ross–Weir algorithm. The results reveal that MWCNTs introduce significant resistive losses (increased ε''), while the annealed Fe layer tunes the magnetic response. This dual-component modification enables independent tuning of the composite's dielectric and magnetic properties. Our study demonstrates a scalable method for transforming low-cost industrial by-products into lightweight, functional materials with tailorable electromagnetic characteristics.

AB - A hierarchical filler was synthesized by growing multi-walled carbon nanotubes (MWCNTs) on aluminosilicate fly ash cenospheres (FACs). The process involved depositing a uniform ferromagnetic Fe catalyst layer (55 nm) via magnetron sputtering, followed by the chemical vapor deposition of a dense MWCNT array (50–60 nm diameter). Composite samples containing 20 wt.% of this filler in a polyurethane matrix were prepared. Their microwave properties were characterized by measuring the scattering parameters (S-parameters) over the 1–13 GHz frequency range. Subsequently, the complex permittivity and permeability were extracted from the S-parameter data using the Nicolson–Ross–Weir algorithm. The results reveal that MWCNTs introduce significant resistive losses (increased ε''), while the annealed Fe layer tunes the magnetic response. This dual-component modification enables independent tuning of the composite's dielectric and magnetic properties. Our study demonstrates a scalable method for transforming low-cost industrial by-products into lightweight, functional materials with tailorable electromagnetic characteristics.

KW - Carbon nanotube

KW - Fly ash cenosphere

KW - Microwave

KW - Permeability

KW - Permittivity

UR - https://www.scopus.com/pages/publications/105023960977

UR - https://www.mendeley.com/catalogue/05e0f45d-be1b-3495-9d67-0f4e88fa4fea/

U2 - 10.1016/j.materresbull.2025.113929

DO - 10.1016/j.materresbull.2025.113929

M3 - Article

VL - 196

JO - Materials Research Bulletin

JF - Materials Research Bulletin

SN - 0025-5408

M1 - 113929

ER -