A Smart Polycage Membrane with Responsive Osmotic Energy Conversion Based on Synchronously Switchable Microporosity...

Area of Science:

• Materials Science
• Membrane Science
• Nanotechnology

Background:

• Membrane science faces challenges in understanding structure-property-performance relationships for molecular separation and energy conversion.
• Fine-tuning membrane microstructure is crucial for controlling performance but remains difficult.
• Developing smart membranes with responsive properties is a key area of research.

Purpose of the Study:

• To design and fabricate smart polycage membranes with concurrently responsive pore apertures and charge properties.
• To investigate the influence of pore size and charge properties on membrane performance, particularly in osmotic energy conversion.
• To explore the molecular-level control of membrane performance through microstructure and charge regulation.

Main Methods:

• Synthesis of an exofunctionalized triskelion cage with aldehyde groups for membrane fabrication and amine sites for postmodification.
• Fabrication of polycage membranes exhibiting pH-responsive porosity and chargeability.
• Demonstration of responsive osmotic energy conversion and molecular simulations to analyze performance.

Main Results:

• Engineered polycage membranes displayed concurrently responsive pore apertures and charge properties.
• A significant, over fourfold, increase in power density was achieved during responsive osmotic energy conversion.
• Molecular simulations supported findings that chargeability plays a more critical role than microporosity in energy conversion performance.

Conclusions:

• Smart polycage membranes offer a viable strategy for reversible regulation of microstructure and charge properties.
• The study provides insights into balancing pore size and chargeability for molecular-level control of membrane performance.
• These findings advance the development of advanced membranes for energy conversion and separation applications.