Energy Harvesting with Single‐Ion‐Selective Nanopores: A Concentration‐Gradient‐Driven Nanofluidic Power Source

TLDR

The study demonstrates a fully abiotic single‑pore nanofluidic system that converts salinity‑gradient Gibbs free energy into electricity and proposes a theoretical framework for its operation. The system employs ion‑selective nanopores to harvest energy from salinity gradients, with a theoretical model describing the resulting electric power generation. The device reaches a maximum of ~26 pW per nanopore, and parallelization can increase power density by one to three orders of magnitude, while calculations show that raising surface‑charge density to 100 mC m⁻² and selecting pore sizes between 10 and 50 nm can further improve performance, making it suitable for powering biomedical devices or clean‑energy recovery plants.

Abstract

Abstract Inspired by biological systems that have the inherent skill to generate considerable bioelectricity from the salt content in fluids with highly selective ion channels and pumps on cell membranes, herein, a fully abiotic single‐pore nanofluidic energy‐harvesting system that efficiently converts Gibbs free energy in the form of a salinity gradient into electricity is demonstrated. The maximum power output with the individual nanopore approaches ∼26 pW. By exploiting parallelization, the estimated power density can be enhanced by one to three orders over previous ion‐exchange membranes. A theoretical description is proposed to explain the power generation with the salinity‐gradient‐driven nanofluidic system. Calculation results suggest that the electric‐power generation and its efficiency can be further optimized by enhancing the surface‐charge density (up to 100 mC m −2 ) and adopting the appropriate nanopore size (between 10 and 50 nm). This facile and cost‐efficient energy‐harvesting system has the potential to power biomedical tiny devices or construct future clean‐energy recovery plants.