Related Experiment Video
Updated: Jun 13, 2025

Proof-of-Concept for Gas-Entrapping Membranes Derived from Water-Loving SiO2/Si/SiO2 Wafers for Green Desalination
Published on: March 1, 2020
Endogenous Asymmetry in Heterogeneous Smectite Membrane Enhancing Salinity Gradient Energy Conversion
Jingwen Liu1, Jiwen Si1, Yi'an Li1
1Key Laboratory of Automobile Materials of Ministry of Education, School of Materials Science and Engineering, Solid Waste Recycling Engineering Research Center of Jilin Province, Open Research Laboratory for Physicochemical Testing Methods of Functional Minerals, Ministry of Natural Resources, Jilin University, Changchun, 130022, China.
None:
To mitigate the concentration polarization caused by non-ohmic resistance, asymmetric ion exchange membranes (IEMs) with nanochannels of comparable Debye length are frequently employed in salinity gradient energy conversion. Conventional asymmetric IEMs always rely on exogenous interventions to tailor their asymmetries as employing polyelectrolytes or modifying substrate porous membranes. Herein, the endogenous asymmetry of the natural smectite family is leveraged to develop composite membranes comprising structurally asymmetric montmorillonite and saponite sheets (MMT-SAP). The fabricated MMT-SAP membrane demonstrates superior ion selectivity and outstanding stability, making it an exceptional salinity gradient energy generation device. Mounted on artificial seawater and river water at 50-fold salinity gradient, the MMT-SAP demonstrates a cation selectivity of 0.96 and a high-power generation output 4.5 W m-2. The maximum power output is found to reach 8.46 W m- 2 at the pH = 11.0. The theoretical study of MMT-SAP reveals that a potential ion migration mechanism within layered mineral channels is determined by two crucial factors: channel size and the heterogeneous structure distribution in the smectite-based membrane.
More Related Videos
Related Concept Videos
Membrane Asymmetry Regulating Transporters
Flippase
Eukaryotic flippases are type-IV P-type ATPases or P4-ATPases belonging to P-type ATPase family proteins that are membrane-bound pumps involved in the ATP-mediated transport of ions and molecules across the membrane. Flippases flip specific phospholipids from the outer to the inner leaflet of a membrane. All P4-ATPases have one...
Asymmetric Lipid Bilayer
Potentiometry: Membrane Electrodes
Osmosis
Mechanisms of Membrane-bending
Membrane bending can happen due to intrinsic changes in lipid composition or extrinsic association with different proteins. The proteins involved...
What is an Electrochemical Gradient?
The chemical gradient relies on differences in the abundance of a substance on the outside versus the inside of a cell and flows from areas of high to low ion concentration. In contrast, the electrical gradient revolves around an...

