An Affordable and Simple Synthesis of Boron Nitride Nanosheets for Terahertz Radiation Shielding

Two-dimensional hexagonal boron nitride (h-BN) is an outstanding material characterized by its low dielectric constant, making it an excellent candidate for absorbing radiation in the high-frequency range, including the terahertz band. This study is dedicated to the preparation of BN nanosheets (BNNs) using a facile and straightforward bottom-up pyrolysis method with inexpensive urea and boric acid. The morphology, crystalline structure, and elemental composition of the as-prepared BNNs were analyzed using powder X-ray diffraction (XRD), Raman spectroscopy, energy-dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM). The results confirmed the successful synthesis of BNNs. The terahertz radiation shielding (TRS) effectiveness of BNNs was evaluated by incorporating them into epoxy resin matrices with varying fractions. The results demonstrate that the 3 mm thick BNN@epoxy resin plate loaded with 10% BNNs exhibits an extraordinary TRS effectiveness of 23.1 dB, making it a highly effective shield against terahertz radiation.