Polyaniline-loaded metal-organic framework MIL-101(Cr): Promising adsorbent for CO₂ capture with increased capacity and selectivity by polyaniline introduction

Highly porous metal-organic framework (MOF), MIL-101(Cr), was modified by introduction of polyaniline (PANI) via ship in bottle strategy in order to utilize basic moieties of PANI in capturing CO₂ effectively from flue gas. PANI@MIL-101(Cr), with suitable PANI concentration, showed highly increased adsorption capacity for CO₂, especially at low pressure of 0.15 atm, even though the porosity of MIL-101(Cr) was decreased upon PANI loading. Moreover, the PANI@MIL-101(Cr) showed increased selectivity for CO₂ (against N₂), compared with pristine MIL-101(Cr); and stable reusability. The observed favorable adsorption of CO₂ on the PANI@MIL-101(Cr) might be because of basic species on well-dispersed PANI on the MOF. The results indicate that modification of porous materials such as MOFs with PANI might be one way to improve performances for CO₂ capture.