Research Seminar of Prof. Gu Chengfrom South China University of Technology

Lecture Time: 10:00 on 24th April, 2019

Lecture Room: C501 of Science and Innovation Building

LectureTitle: Design of porous materials with local flexibility

Abstract

Design of the gas-diffusion process in a porous material is challenging because a contracted pore aperture is a prerequisite, while the channel traffic of guest molecules is regulated by the flexible and dynamic motions of nanochannels.[1-3]Herein, we present rational design of a diffusion-regulatory system in a porous coordination polymer (PCP) in which flip–flop molecular motions within the framework structure provide kinetic gate functions enabling efficient gas separation and storage.[4]The PCP shows significant temperature-responsive adsorption in which the adsorbate molecules are differentiated by each gate-admission temperature, facilitating kinetics-based gas separations of oxygen/argon and ethylene/ethane with high selectivities of ~350 and ~75, respectively. Additionally, we demonstrate the long-lasting physical encapsulation of ethylene at ambient conditions, owing to strongly impeded diffusion in distinctive nanochannels.

Figure1Schematic representation of diffusion-regulatory pore systems.

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