Superfast Adsorption-Disinfection Cryogels Decorated with Cellulose Nanocrystal/Zinc Oxide Nanorod Clusters for Water Purifying Microdevices

摘要

In outdoor activities and disaster environments, a portable microdevice is very important for the rapid purification of field drinking water. Smart cryogels were fabricated by one-pot copolymerization among acrylamide (AM) monomers, 2-(dimethylamino) ethyl methacrylate (DMAEMA) monomers, and cellulose nanocrystal/zinc oxide (CNC/ZnO) nanorod clusters through a simple ice-template method. The effect of nanohybrid contents on microstructural, thermal, swelling, and antibacterial properties of cryogels-ZnO was investigated. With the incorporation of 1 wt % CNC/ZnO, the cryogels showed macroporous-networked structures with a high porosity of 93% and homogeneous nanorod clusters on the macroporous wall. Cryogels-ZnO showed high mechanical strength in both dry and wet states, an adsorption capacity of 30.8 g/g, superfast adsorption time (2.5 s), and a stable swelling-deswelling ability after 10 cycles. Additionally, the adsorption capacity of cryogels-ZnO presented a dual temperature/pH response. Upon treatment of the simulated field water with cryogels-ZnO for 45 min, the cfu amounts of simulated field water were decreased from 1862 to 6 cfu/mL. This cfu amount for treated water was much lower than the 100 cfu/mL of China's national drinking water standard. In addition, cryogels-ZnO can effectively handle 14.3-16.1 g/g of disinfected drinking water by manual compression. Such cryogels-ZnO exhibited a great potential for field drinking-water-purifying microdevices.