title: Tuning the host-guest interactions in a phosphine coordination polymer through different types of post-synthetic modification.
abstract: The porous Phosphine Coordination Material, PCM-10 contains abundant free P(III) donor sites that can be subjected to a variety of post-synthetic modifications. The diverse P(III)/P(V) organic reactivity and coordination chemistry available to aryl phosphines have been exploited to decorate the pores of PCM-10, allowing for an extensive structure-function study. Polar P═O moieties, charged P(+)-CH3 phosphonium species with exchangeable coanions (I(-), F(-), BF4(-), and PF6(-)) and P-AuCl groups have been successfully post-synthetically incorporated. These modifications directly affect the strength of the resulting host-guest interactions, as demonstrated by comparative sorption studies of CO2, H2, and other gases in the solid-state. Broad tunability of the enthalpy of CO2 adsorption is observed: incorporation of BF4(-) ions inside the pores of PCM-10 results in 24% enhancement of the isosteric adsorption enthalpy of CO2 compared to the parent material, while F(-) anions induce a 36% reduction. Meanwhile, AuCl-decorated PCM-10 shows a high H2 sorption capacity of 4.72 wt % at 77 K and 1.0 bar, versus only 0.63 wt % in the unmodified material.
authors.affiliation: Department of Chemistry, The University of Texas at Austin , 105 E 24th Street A5300, Welch Hall 2.204, Austin, Texas 78712-1224, United States.
authors.forename: Ana J
authors.initials: AJ
authors.lastname: Nuñez
authors.forename: Maxwell S
authors.initials: MS
authors.lastname: Chang
authors.forename: Ilich A
authors.initials: IA
authors.lastname: Ibarra
authors.forename: Simon M
authors.initials: SM
authors.lastname: Humphrey