ZnO QD and Nanocellulose Mixing

The above-synthesized ZnO QD suspension is diluted to a ZnO QD concentration of 1 mg/ml by adding DI-water. The nanocellulose solution is diluted to 0.1 wt% with DI-water and degassed for half hour before mixing. A volume ratio of 0.75:1 of ZnO QD and nanocellulose suspensions are mixed in a glass bottle and sonicated for 5 mins with an ultrasonic homogenizer (Biologics, Inc., Model 3000). The product is centrifuged under 2000 rpm for 10 mins to precipitate out larger clusters. The supernatant is then diluted again to half concentration by adding DI-water and the resulting solution can be readily used for active paper making.