Polymer-aided microstructuring of moisture-stable GO-hybridized MOFs for carbon dioxide capture

MOF-based hybrid adsorbents for carbon capture are gaining increased attention as they can enhance key performance properties and scalability of MOFs. Yet, structuring these complex materials into mm-sized shaped particles to be used in actual process while maintaining the performance characteristics of the original powdered hybrids is challenging. In this work, a water-stable MOF (MIL-101(Cr)) was hybridized with graphene oxide (GO) yielding a hybrid adsorbent with enhanced CO2 capture performance, and the hybrid was then structured into mechanically robust spherical polyacrylonitrile-based beads of similar to 2-3 mm in size exhibiting hierarchical porosity and high MOF loading (up to 80%) using a novel, simple, and scalable strategy. The powdered hybrid adsorbent with an optimum GO loading of 6 wt.% exhibited a 55% higher CO2 adsorption capacity and a 48% higher CO2/N-2 selectivity than those of the parent MOF at 298 K and 1 bar, while the structured analogue provided high dispersion of the MOF@GO powder and preserved the CO2 adsorption performance and porosity characteristics of the original MOF@GO, making the resulting beads suitable and ready-to-use for practical CO2 capture application.

Automated summary

This paper presents a study on the development of hybrid adsorbents for carbon capture. The researchers successfully hybridized a water-stable MOF with graphene oxide, yielding a hybrid adsorbent with enhanced CO2 capture performance. They then structured the hybrid into mechanically robust spherical beads using a novel and scalable strategy. The results showed that the structured beads maintained the performance characteristics of the original hybrid and exhibited high CO2 adsorption capacity, making them suitable for practical CO2 capture applications.