Facile fabrication of Bi₂O₃/MWCNTs/CAB nanocomposite films via pulsed laser ablation for enhanced electromagnetic shielding

With the rapid advancement of flexible electronics and wireless communication technologies, the development of lightweight, high-performance electromagnetic interference (EMI) shielding materials has become critically important. Pulsed laser ablation offers a clean, surfactant-free, and controllable synthesis route for integrating functional nanostructures into polymer matrices for efficient EMI shielding. This study presents a novel approach for fabricating a Bi₂O₃/MWCNTs/CAB flexible polymer via pulsed laser ablation for electromagnetic shielding applications. The developed materials were extensively characterized using different techniques, including X-ray diffraction (XRD), Raman spectroscopy, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and contact angle measurements. The transmission amplitude and complex conductivity in the terahertz frequency range, along with the shielding effectiveness (SE) in the X-band microwave regime, were systematically evaluated. Compared to pure CAB, which showed resonance SE peaks of ∼3 dB at 9.08 GHz and 11.52 GHz, the CNTs/CAB nanocomposite exhibited broadband SE improvements reaching ∼2.7 dB across the X-band. Interestingly, the addition of Bi₂O₃ led to a more uniform but lower SE (∼0.6 dB), suggesting potential for electromagnetic-induced transparency-tunable applications. Given its facile fabrication process and ultrathin structure, the pulsed laser-fabricated MWCNTs/CAB nanocomposite film demonstrates strong potential for next-generation electromagnetic shielding applications.