Razi University

Conducted by a Researcher at Razi University

Development of Bio-Based Metacomposites with Electromagnetic Shielding Properties for Applications in Flexible Electronics

A researcher at Razi University has successfully developed bio-based metacomposites exhibiting electromagnetic impermeability, with promising applications in flexible electronics. Through an innovative research project, the Razi University researcher designed and fabricated bio-based metacomposites with tunable electromagnetic properties, suitable for electromagnetic interference (EMI) shielding as well as for the development of flexible electronic devices.

This research, entitled “Electromagnetic and Functional Performance of Bambuseae/MWCNT/MnFe₂O₄/PVA Metacomposites with Tunable Negative Permittivity for EMI Shielding and Flexible Electronics,” was conducted by Dr. Reza Gholipur, a faculty member of the Department of Physics, Faculty of Science, Razi University, in collaboration with Mohammad Moein Abbasi and Mahfooz Maazi. The study has been published in the international journal Scientific Reports (Nature Publishing Group).

In this work, metacomposites based on poly(vinyl alcohol) (PVA) incorporating multi-walled carbon nanotubes (MWCNTs), manganese–iron ferrite oxide (MnFe₂O₄), and natural bamboo fibers (Bambuseae) were synthesized using the sol–gel method. The primary objective was to achieve materials with negative electrical permittivity and effective electromagnetic wave absorption and reflection over a broad frequency range.

The results demonstrated that the electromagnetic properties of the material can be effectively tuned by adjusting the MWCNT content within the composite structure. At specific MWCNT loadings (0.064 and 0.256 g), clear negative permittivity behavior was observed, attributed to plasmonic oscillations and Lorentz-type resonance mechanisms within the composite. This property led to significant impedance mismatch and efficient reflection of incident electromagnetic waves from the material surface.

The designed metacomposites achieved a shielding effectiveness of 43.28 dB at a thickness of only 1 mm, indicating remarkable performance in both absorption and reflection of unwanted electromagnetic radiation. Moreover, the formation of conductive networks and polarized regions induced by the presence of carbon nanotubes enhanced wave attenuation and increased radiative energy dissipation.

 

In addition to their shielding capability, these metacomposites exhibited high efficiency in photoelectric conversion and strong mechanical stability, making them suitable for use in flexible electronic devices such as light-dependent resistors (LDRs). Notably, they maintained stable performance even under harsh environmental conditions.

According to Dr. Gholipour, “This research represents a step toward the development of advanced materials that integrate bio-based resources with nanotechnology, simultaneously providing environmental sustainability and high electromagnetic performance. Such materials can be employed in modern electronic industries, telecommunication equipment, and EMI protection systems.”

Due to their bio-based nature, non-toxicity, low cost, and high durability, the materials introduced in this study represent a promising option for advancing green technologies in the fields of flexible electronics and electromagnetic shielding.

شناسه : 35511694