Enhanced Power Output through Charged Nanopores

Charged nanochannels are promising green energy candidates and their operation is investigated in this study. Regimes of high performance are identified by spanning the large parameter space in driving force, impurities, and geometry. In a simple channel when driving forces are coupled, for example an electric potential and salt concentration gradient, a synergistic increase in electric current is reported. Using a Janus nanopore consisting of regions with different diameter and surface charge can improve performance relative to a simple geometry and this effect is shown to be highly dependent on characteristic salt concentration and choice of driving force. Coupling complex geometry with divalent impurity provides a third route to enhanced output. Calculations over the large design space are performed using the coupling of Poisson electrostatics, Nernst-Planck transport, and Navier-Stokes hydrodynamics. The continuum equations have been validated against full atomistic simulations for a sample Janus nanopore.