An ultrafine spider-like carbon nanonet for high performance air filters, health monitoring sensors, and green energy

generators†.

Abstract:We report an innovative approach for fabricating a gradient dual nanonet (NF@CNT) consisting of poly(vinyl alcohol-co-ethylene) (PVA-co-PE) nanofibers with a diameter of 0.68 ± 0.15 mm and ultrafine spider-like nanonets with a diameter of 23.30 ± 6.67 nm. The spider-like nanonet formation mechanism is probably due to the hydrogen bonding interactions between single wall carbon nanotubes (SWCNTs) and PVA-co-PE nanofibers or between SWCNTs.The NF@CNT-2 air filter exhibits a relatively high water vapor transmission rate (WVTR) of   4732.63 ± 626.28 g (m² d)⁻¹ , a highfiltration efficiency of 95.62 ± 0.52%, and a low pressure drop of 105.33 ± 1.53 Pa. Additionally, it can be assembled as a resistance sensor to detect human motion, such as finger bending and releasing, as well as physiological signals including wrist pulse rate (66 times per min), vocal recognition, and respiration rate (normal 16 times per min, after exercise 55–56 times per min). Furthermore, itcan also be reused as a transpiration driven electrokinetic power generator (TEPG), with a size of 66 mm × 10 mm providing amaximum open circuit voltage (Voc) of 0.57 V by dripping 85 mL of 0.1 M ferric chloride solution, and six units serially can power a red LED and a calculator, respectively.

Xiong Zy, Xia M, Guo X, et al. An ultrafine spider-like carbon nanonet for high performance air filters, health monitoring sensors, and green energy generators†[J]. Journal of Materials Chemistry A.