This study aims to convert composite textile structures composed of nonwoven and woven fabrics produced from cotton–jute wastes into activated carbon textile structures and investigate the possibilities of using them for electromagnetic shielding applications. To this end, the novel contribution of this study is that it shows that directly carbonized nonwoven textile via self-purging microwave pyrolysis can provide Electromagnetic Interference (EMI) shielding without any processing, including cleaning. Textile carbonization is generally achieved with conventional heating methods, using inert gas and long processing times. In the present study, nonwoven fabric from cotton–jute waste was converted into an activated carbon textile structure in a shorter time via microwaves without inert gas. Due to its polar structure, FeCl₃ has been used as a microwave absorbent, providing homogeneous heating in the microwave and acting as an activating agent to serve dual purposes in the carbonization process. The maximum surface area (789.9 m²/g) was obtained for 5% FeCl₃. The carbonized composite textile structure has a maximum of 39.4 dB at 1 GHz of EMI shielding effectiveness for 10% FeCl₃, which corresponds to an excellent grade for general use and a moderate grade for professional use, exceeding the acceptable range for industrial and commercial applications of 20 dB, according to FTTS-FA-003.

Increasing amounts of waste resulting from over-consumption carry substantial risks for human and environmental health, and disposing of this waste requires enormous amounts of energy. As a result, waste-to-wealth and circular economy approaches have gained attention in both academia and the commercial sector in recent years. Accordingly, this study aims to develop electromagnetic shielding materials by converting non-conductive waste textiles into conductive value-added product and porous fabrics by carbonizing the structure itself rather than by adding any conductive particles. To this end, the novel contribution of the present study is that waste textiles were converted into activated carbon in a shorter time and without compromising the integrity of the fibrous network via microwave pyrolysis without inert gas. Sulfuric acid was used as a dehydration and activation agent, suppressing the release of volatile organic substances and eliminating greenhouse gas emissions. This approach also increased product yield and reduced energy consumption and sample shrinkage. The structures of the activated carbon textile showed EMI shielding within 20–30 dB (99.9% attenuation) in the 1–6 GHz frequency range. The maximum SSE/t value of 950.71 dB·cm²·g⁻¹ was obtained with the microwave post-treated activated carbon textile. Micropores were dominant characteristics of these materials, and pore diameters increased with increased acid concentration. The maximum surface area of 383.92 m²/g was obtained with 8% acid. Ultrasound treatment reduced water-energy consumption and cost. Only 5 min of microwave post-treatment increased textile conductivity and thermal stability and contributed positively to electromagnetic shielding.

This study investigates innovative pathways for sustainable carbonization by comparing the performance and environmental impacts of microwave and muffle furnace heating technologies in the production of activated carbon from textile waste. The muffle furnace process demonstrated superior material properties, achieving a higher surface area (538.42 m²/g) and exceptional electromagnetic interference (EMI) shielding effectiveness (47.56 dB at 2 GHz). It also exhibited better electrical conductivity, making it highly suitable for EMI shielding applications. Conversely, the microwave method, while yielding a lower surface area (383.92 m²/g) and EMI shielding (38.60 dB at 1 GHz), showed promising electrical conductivity and remarkable advantages in time and energy efficiency. A novel Green Performance Efficiency (GPE) metric was developed to evaluate the sustainability of these processes holistically, integrating performance parameters such as EMI shielding with energy consumption and process duration. The GPE analysis revealed that the microwave method outperformed the muffle furnace in terms of energy and time efficiency, achieving a significantly higher GPE score. However, the muffle furnace method excelled in material performance metrics, highlighting the trade-offs between sustainability and functionality. The findings not only provide a standardized framework for evaluating and optimizing carbonization technologies but also offer actionable insights into balancing efficiency and performance in sustainable activated carbon production. This research paves the way for advanced applications in EMI shielding, energy storage, and sustainable material development, demonstrating the potential of GPE as a benchmark for green technology innovation.