Single-electron non-adiabatic tunneling through a metal nanoparticle with due account of the solvent dynamic effect: The generalization of the “orthodox” theory

A theory of electron tunneling through a small metal nanoparticle (NP) which is governed both by the charging effect and the effect of the solvent reorganization on the tunnel current is presented. The exact expression for the rate constant of electron transfer from an electrode to NP which is valid for all values of the reorganization Gibbs energy Er, bias voltage and overpotential is obtained in the non-adiabatic limit. The tunnel current/overpotential relations are studied for different values of the bias voltage and Er.

Research Highlights
► We suggest a theory of single electron non-adiabatic tunneling through a metal nanoparticle (NP).
► A theory takes into account both the charging as well as the solvent dynamic effects.
► We obtain a new expression for the rate constant of electron transfer from an electrode to NP.
► We show that the width of the charging peak depends on the solvent reorganization energy.
► We show that values of the tunnel current depend on the reorganization energy.