We developed a high-efficiency rotating triboelectric nanogenerator (R-TENG) enhanced polyimide (PI) nanofiber air filter for particulate matter (PM) removal in ambient atmosphere. The PI electrospinning nanofiber film exhibited high removal efficiency for the PM particles that have diameters larger than 0.5 μm. When the R-TENG is connected, the removal efficiency of the filter is enhanced, especially when the particle diameters of the PM are smaller than 100 nm. The highest removal efficiency is 90.6% for particles with a diameter of 33.4 nm and the highest efficiency enhancement reaches 207.8% at the diameter of 76.4 nm where the removal efficiency enhanced from 27.1% to 83.6%. This technology with zero ozone release and low pressure drop offers an approach for air cleaning and haze treatment.

The triboelectric nanogenerator (TENG) is a promising energy harvesting technology that can convert mechanical energy into electricity and can be used as self-powered active sensors. However, previous studies are mostly carried out at room temperature without considering the temperature effect on the electrical performance of TENGs, which is critical for the application of electronics powered by TENGs in different regions in the world. In the present work, a TENG that worked in the single-electrode and contactseparation mode is utilized to reveal the influence of environment temperature on the electrical performance of TENG. The electrical performance of the TENG shows a decreasing tendency, as the temperature rises from À20 to 150 C, which is controlled by the temperature-induced changes in the ability of storing and gaining electrons for polytetrafluoroethylene (PTFE). The storing electron ability change of PTFE is attributed to two aspects: one is the reduction of relative permittivity of PTFE sheet as the temperature increases, and the other is the variations of effective defects such as the escape of trapped charges in shallow traps and surface oxidation under the effect of temperature perturbation. This work can provide useful information for the application of TENG in both electric power generation and selfpowered sensors in the harsh environment. Experimental SectionFabrication of the TENG: The TENG in this work was made up of a Al foil (55 Â 55 Â 1 mm), polyethylene terephthalate (PET) insulation tapes, PTFE sheets (55 Â 55 Â 3 mm). The PTFE sheet is a commercial product