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Electrochemical Studies Carried out in Deep Eutectic Solvents and Colloidal Suspensions
a
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Figure 2. Schematic representation of anodic dissolution technique for the electrodeposition of Au@Pd nanoparticle in DES medium (b) SEM images of graphite rod modified with Au@Pd NPs
found to obey Michaelis Menten equation. The electrochemical method employed here with the colloidal medium acts as a simple robust method to follow enzymatic reactions in a soft medium mimicking biological environment.
The sharp reversible sol-gel phase transition of the colloid at 55 oC was utilised as a matrix for dispersing nanomaterials such as CNT, graphene and metal nanoparticles. A few of such dispersions of nanoparticles (CNT, Graphene, Fe3O4 NP, AgNP) in the colloid are shown in the Fig.3. A vial containing 0.5 mg /ml nanoparticles
Figure 3. Photographs of the vial containing the colloidal suspension and a teflon coated magnetic pellet at (a) T > 600C and (b) RT
in sol were initially sonicated at a temperature of about 50-60 oC. As soon as a stable dispersion of nanoparticles was achieved, the nanoparticle matrix was plunged into cold water. The sudden drop in temperature brings about the phase transition of sol gel, thus freezing the well dispersed state of nanoparticles brought about by sonication. The nanoparticle dispersion obtained in the colloid has the potential for use in electrochemical biosensors, electronic and optoelectronic applications.
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