MnO2 nanoflakes/cellulose nanofibres aerogel based on ultrasonication for high-performance water desalination
MnO2 nanoflakes/cellulose nanofibres aerogel (MCNF) has been fabricated via methods of redox reaction and ultrasonication. SEM and TEM images demonstrated that core-shell structure of ultrathin MnO2 nanoflakes/cellulose nanofibres was successfully obtained via ultrasonic control, in which MCNF possessed 3D structure. Nitrogen adsorption analysis showed that the MCNF composites had a larger specific surface area compared with CNF, which was due to the inserted CNF inhibiting the aggregation of MnO2. The desalination capacity was evaluated by adsorptive experiment in a lot of ions (Ca2+, Mg2+, Na+ and sea water) in aqueous solution. MCNF exhibited excellent desalination behavior towards ions in sea water depended on both the strength of efficient positive ionic charge and ionic radius. More interesting, the regenerated MCNF after the initial HCl and subsequent KOH treatment couldbe repeatedly used after ten adsorption/desorption cycles without obvious degradation of performance. Moreover, with high desalination efficiency and reusability, and ease of separation operation, the aerogel would be a candidate for desalination in practical application.