A class of nanomaterials made from metal nanoparticles functionalized with charged organic ligands shows great potential,in which the electrical conduc-tance through charged metal nanoparticles is modulated by the dynamic gradients both of mobile counterions surrounding the nanoparticles and conduction electrons on the nanoparticle cores.The gradients are unique in that they persist throughout the entire material and are long lived.These derive from the coupling between ion and electron distributions and are essential for controlling the transient electronic prop-erties of the nanomaterial.The Nernst-Planck equation has been used previously to describe electron transport through nanoparticle materials.Here,we used the PNP model to simulate ion and electron coupling transport through metal nanoparticle ma-terials.In this process,the counterions and the conduction electrons can(1)diffuse in response to concentration gradients and(2)migrate due to local electric fields.In the case of electrons,these continuum transport mechanisms ultimately derive from the microscopic processes by which electrons tunnel and/or hop from one nanoparticle core to another.In the absence of conduction electrons,mobile ions can migrate only small distances(of the order of the Debye length)before completely screening any applied electric field.The simulation results agree well with experimental results.