Esoteric CO adsorption by CuCl-NiCl2 embedded microporous MIL-101 (Cr)

Abstract

Abstract A microporous MIL-101 (Cr) material with considerably high surface area of 3084\u2009m2 \u2009g−1 and high total volume of 2.04\u2009cm3 \u2009g−1 was used to host CuCl and NiCl2 species. Cu (II) was completely reduced to Cu (I) in the MIL-101 (Cr), while maintaining the Ni (II) in the host structures in order to effect the π-complexation between CO and the CuCl-NiCl2 MIL-101 (Cr) sample for improved CO adsorption. Ni (II) species were found to promote the reduction of Cu (II) and inhibit the agglomeration of copper crystals into large-size crystals, which enhanced the CO adsorption. The CuCl-NiCl2 MIL-101 (Cr) was capable of reaching a maximum CO adsorption of ca. ∼3.22\u2009mmol g−1 and IAST-predicted CO/N2 selectivity of ca. ∼405. The sample was also regenerable for an extended period of time by a mere pressure swing without a post-treatment, making it a promising candidate for an industrial scale CO separation, enrichment and purification at ambient conditions.