Hydrothermal synthesis of polymer composite aerogels for effective electromagnetic interference shielding

The ever-expanding horizons of smart electronic gadgets have been contributing significantly to electromagnetic radiation pollution, in recent years. Hence the development of light and eco-friendly electromagnetic interference (EMI) shields become critical. Ideally, such shield should protect a given system from undesirable EM waves by absorption or reflection shielding mechanism. Here, we synthesized V₂O₅ hydrogel via a simple one-pot hydrothermal route and the nanowire network inside the gel was polymerized by aniline. One of the highlights of the less laborious and low cost method of preparation is that, it involves only a few chemicals, thereby leaving less carbon footprint. The mesoporous composite aerogels obtained after freeze-drying has a very low density of ~0.03 g/cc and they exhibit excellent shielding performance (71.2 dB), superior specific shielding efficiency (1338.8 dB cm³ /g) and good green index (1.02). The porous structure of the materials and successful incorporation of polyaniline was confirmed by scanning and transmission electron microscopy and various spectroscopic analyses. Nevertheless, V₂O₅-polyaniline aerogels have high conductivity, ample mechanical strength and absorption dominant shielding efficiency in the entire X, Ku, and K band frequency. These ultra-low dense, 'easy-to-prepare' aerogels could be used as future EMI shields in portable devices and avionic applications