Electrostatic potential fluctuations and electron transfer kinetics of gold nanoparticles in aqueous solution

We have implemented a semi-classical simulation method to calculate the charge distribution within a metal nanoparticle. We have used this method to determine electron transfer rates from gold nanoparticles in aqueous solution with the number of gold atoms ranging from 13 to 561. Our simulation results demonstrate that as the nanoparticle decreases in size, the fluctuations in electrostatic potential and the vertical energy gap increase, subsequently causing an increase in the electron transfer rate. Our results highlight the role of molecular-scale fluctuations in chemical reactivity and will be of general interest to researchers studying heterogeneous catalysis.