Effect of temperature on zeta potential of functionalized gold nanorod

Abstract

Nanorod immersed in electrolyte solution finds many applications in different fields encompassing biotechnology, drug delivery, micro-/nanofabrication, etc. In this article, a comprehensive theoretical model has been developed and solved numerically to study the effect of nanorod temperature on its potential distribution for different salt concentrations and solution pH. The study considers surface properties of nanorod functionalized with 11-MUA at higher solution temperatures in both the presence and absence of temperature gradient to analyze contribution of thermodiffusion (in the presence of temperature gradient) and different solution properties like ionic mobility and solution permittivity (in the absence of temperature gradient). Effect of solution temperature on nanorod zeta potential in the absence of temperature gradient has been shown through numerical study along with analytical verification. Present results show that zeta potential of nanorod functionalized with 11-MUA is negative, and with increasing nanorod temperature its zeta potential value increases. In the presence of thermodiffusion, increment in zeta potential value strongly depends on solution pH, whereas in the absence of temperature gradient increment in nanorod zeta potential value solely depends on solution permittivity and absolute solution temperature.