Sustainable self-powered PVDF fibrous filter medias based on triboelectric nanogenerator with efficient dust collection for personal occupational protection.

The filtration efficiency of traditional filter medias is relatively low for the removal of fine dusts ranging from 10 to 1000 nm, which is seriously harmful to human health. In this study, a novel self-powered fibrous filter media based on polyvinylidene fluoride/cellulose acetate (PVDF/CA) electrospun nanofibrous membrane and a triboelectric nanogenerator (TENG) driven by respiration (R-TENG) was developed. Two different electrets including hydroxylation graphene (G-OH) and cesium lead halide inorganic chalcocite (CsPbIBr) were added to improve the filtration performance of PVDF/CA membranes. The results showed that the filtration efficiency of the PVDF/CA/G-OH membrane for NaCl particles arrived at 96.8 %, with a pressure drop of 132.5 Pa, a tensile strength of 2.88 MPa and permeability of 221.45 mm/s. Compared with the R-TENG fabricated by the PVDF/CA membrane, the short-circuit current, the open-circuit voltage and the transferred charge of the R-TENG fabricated by the PVDF/CA/G-OH membrane (2.91 μA, 12.84 V and 14.23 nC) largely increased, representing a increase of 2.03, 1.74 and 1.99 times respectively. On the basis of the R-TENG, the self-powered fibrous filter medias showed a higher filtration efficiency and lower pressure drop for the fine particulates after continuous use for 240 min at the huge flow rates of 85 L/min. Combined with the COMSOL simulation, it could be found that R-TENG continuously provided electrostatic charge on the fibrous membranes and promoted the ionization of gas molecules to effectively capture the fine dusts, exhibiting an excellent air purification method with great prospects in wearable breathing devices for occupational health protection.