Power Generation from Salinity Gradient by Reverse Electrodialysis in Silicon Nitride Nanopores

Abstract

Solid-state nanopores have shown great potential in investigating salinity gradient energy generation as a renewable power generator. In this work, various diameter silicon nitride (Si3N[Formula: see text] nanopores were fabricated to investigate the power generation between two potassium chloride solutions with different concentration gradient ratios by reverse electrodialysis. The maximal estimated power density of a Si3N4 nanopore measured experimentally can be high to 16[Formula: see text]649Wm[Formula: see text]. To compare with the single Si3N4 nanopore, multiple nanopores array has also been investigated. The equivalent circuit model of multiple Si3N4 nanopores array generator is quantitatively constructed by massive reproducible experimental data and theoretical derivation. For nanopore array, the osmotic current basically keep a linear growth with the number of the nanopores at every concentration ratio. While, the osmotic voltage is basically independent on the number of nanopore. The power generation circuit of the nanopore array can be regarded as a parallel circuit of multiple nanopores. Power generation from concentration gradients in Si3N4 nanopores could be widely used in a variety of applications like ultra-low power devices and micro-nano electromechanical systems.