Ambient particulate matter (PM) pollution has posed serious threats to global environment and public health. However, high efficient filtration of submicron particles, so named 'secondary pollution' caused by e.g. bacterial growth in filters and the use of non-degradable filter materials, remains a serious challenge. In this study, Polyvinyl alcohol (PVA) and konjac glucomannan (KGM) based nanofiber membranes, loaded with ZnO nanoparticles, were prepared through green electrospinning and eco-friendly thermal crosslinking. Thus obtained fibrous membranes do not only show high-efficient air-filtration performance but also show superior photocatalytic activity and antibacterial activity. The filtration efficiency of the ZnO@PVA/KGM membranes for ultrafine particles (300nm) were higher than 99.99%, being superior to commercial HEPA filters. By virtue of the high photocatalytic activity, the Methyl orange (MO) were efficiently decolorized with a removal efficiency of more than 98% at an initial concentration of 20 mgL-1 under 120 min solar irradiation. The multifunctional membrane with high removal efficiency, low flow resistance, superior photocatalytic activity and antibacterial activity was successfully achieved. It's conceivable that the combination of biodegradable polymer and active metal particle would form

The conventional blending fabrication for thin-film nanocomposite (TFN) membranes is to disperse porous fillers in aqueous/organic phases prior to interfacial polymerization, and the aggregation of fillers may lead to the significant decrease in membrane performance. To overcome this limitation, we proposed a novel layer-by-layer (LBL) fabrication to prepare a polyamide (PA)/ZIF-8 nanocomposite membrane with a multilayer structure: a porous substrate, a ZIF-8 interlayer, and a PA coating layer. The PA/ZIF-8 (LBL) membrane for nanofiltration applications was prepared by growing an interlayer of ZIF-8 nanoparticles on an ultrafiltration membrane through in situ growth and then coating it with an ultrathin PA layer through interfacial polymerization. The obtained PA/ZIF-8 (LBL) membrane exhibited both better permeance and selectivity than did the conventional PA/ZIF-8 TFN membrane because of the ZIF-8 in situ growth producing a ZIF-8 interlayer with more ZIF-8 nanoparticles but fewer aggregates. Compared with the pure PA membrane (the flux of 11.2 kg/m(2)/h and rejection of 99.6%) for dye removal, the obtained PA/ZIF-8 (LBL) membranes achieved a significant improvement in membrane permeance and selectivity. (Flux was up to 27.1 kg/m(2)/h, and the rejection reaches 99.8%.) This LBL fabrication is a promising methodology for other polymer nanocomposite membranes simultaneously having high permeance and good selectivity.

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BA-loaded cellulose-graft-poly(l-lactic acid) nanoparticles were fabricated by employing cellulose and poly(l-lactic acid) as materials and betulinic acid as a model drug. The nanoparticles have appropriate size and excellent antitumor activities.