Green Nanotechnology and Colloids Laboratory

Seeking sustainable solutions to solve current and future problems.

Colloidal Properties of Nanoparticles

The effective use of nanoparticles requires adequate control of their colloidal properties. Individually dispersed nanoparticles, or nanoparticle clusters, can both be beneficial for a variety of applications including underground energy production, geological carbon sequestration, nanocomposite materials and drug delivery. Our research seeks to control the dispersion and aggregation of bio-based nanoparticles via molecular scale manipulation of interfacial interactions. Non-toxic and renewable cellulose nanocrystals (CNC) shown in Figure 1, are of special interest for our research group. Cellulose Nanocrystals (CNC)

Expirement wood pulp dissolved in water
Figure 1. CNCs isolated from wood pulp. Left: AFM image of CNC, right: 1 wt% CNC suspension in DI water.

Nanoparticle Stabilized Foams and Emulsions

CNCs have been used to successfully stabilized dodecane/seawater emulsions. Examples of dodecane and synthetic seawater (SSW) emulsions are shown in Figure 2. The nanocrystals emulsify the mixtures in all proportions and remain stable for weeks with little creaming. Emulsions in highly concentrated brines have also been prepared in our lab. Applications for Pickering emulsions include underground sequestration of CO 2 , oil bioremediation,low energy separations and energy generation.

Jars on a shelf
Figure 2. CNC stabilized dodecane in synthetic seawater (SSW) emulsions. From left to right: 90/10, 75/25 and 50/50 dodecane/SSW. Dodecane/SSW Pickering Emulsions

Advanced Nanocomposites

Nanocellulose can be used as effective nanofillers for multifunctional polymeric materials by enhancing mechanical properties, hydrophobicity/hydrophilicity and thermal insulation. Current research with thermoset epoxy resins have resulted in increased storage and loss moduli upon addition of CNCs, leading to a simultaneous enhancement of stiffness and energy dissipation characteristics. These enhanced resins can potentially lead to light weight structural materials for the construction, automotive and aerospace industries. CNCs and cellulose nanofibers (CNFs) are also being explored as multifunctional coatings for packaging applications.