Freestanding MoS2@carbonized cellulose aerogel derived from waste cotton for sustainable and highly efficient particulate matter capturing

Particulate matter (PM) has been the main contributor to air pollution that has posed a serious threat to human health. Here we designed an environmentally-friendly conductive air filter for sustainable and highly efficient PM particle capturing under the assistance of an electrostatic field. Waste cotton fibers were used as the raw materials to prepare carbonized cellulose aerogel. Then molybdenum disulfide was vertically grown on the aerogel surface. Due to the high specific surface area, excellent electrical conductivity of the carbonized aerogel, and the strong electrostatic force between the air filter and PM particles, the removal efficiency of PM2.5 and PM10 is over 99.91% and 99.95%, respectively. The high efficiency can be maintained for up to 600 min demonstration (PM2.5 > 98.6%, PM10 > 99.1%). This composite air filter also exhibited excellent reusability: the adsorption efficiency was greater than 97.80% after 5 cycles, and regeneration can be simply realized by washing. The current work not only provides a new strategy to designing more efficient PM filter, but also suggests an avenue to recycle waste cotton fibers.