Viscosity decoupled charge transport in surface functionalized ZnS nanoparticle dispersed imidazolium ionanofluids

Publication date: Available online 6 April 2019Source: Materials Research BulletinAuthor(s): Debalina Deb, Bula Dutta, Subhratanu BhattacharyaAbstractThe mechanism of charge transport in ionic liquid functionalized ZnS nanoparticles dispersed imidazolium-based ionanofluids are investigated combining impedance spectroscopy, viscosity measurement and differential scanning calorimetry. The viscosity enhances from 76 mPa. S to 229 mPa. S at room temperature in 0 to 20 wt% of functionalised nanoparticles addition in the ionic liquid. The conductivity and permittivity spectra are dominated on the low-frequency side by electrode polarization effects. Using the Poisson − Nernst − Planck (PNP) electro-diffusion equations enables us to determine the dc conductivity, ion diffusivity and hopping length of mobile ions and their nature of thermal activation. A decoupling of ion transport with viscosity is observed in the ionanofluids within the entire temperature range and for the 15.0 wt% nanoparticle inserted nanofluid conductivity reaches a maximum value (2.5 mS/cm at 30 °C). The physical explanation regarding the possible origin of the observed remarkable decoupling is proposed.Graphical abstract
Source: Materials Research Bulletin - Category: Materials Science Source Type: research