ABSTRACT:The water loading capacity and water cycle stability (40 adsorption/ desorption cycles) of four nitro-or amino-functionalized MIL-101Cr materials (1−4) is assessed for heat transformation applications. Amino-or nitro-functionalized (1, 3) and partially amino-or nitro-functionalized MIL-101Cr (2, 4) have been synthesized through time-controlled postsynthetic modification of MIL-101Cr. The partially functionalized materials (2, 4) contain about 78 mol % amino-or nitro-functionalized terephthalate linker. Hydrophilic nitro or amino functionalities were introduced into MIL-101Cr in order to achieve water loading at lower p/p 0 values for possible use in thermally driven adsorption chillers or heat pumps. Among the four materials studied, fully aminated MIL-101Cr-NH 2 , 1, and partially aminated MIL-101Cr-pNH 2 , 2, showed the best water loadings (about 1.0 gH 2 O/gMIL) as well as water stability over 40 adsorption−desorption cycles. After 40 cycles, the X-ray powder diffractogram and Brunauer−Emmett−Teller (BET) surface determination of amino-functionalized materials indicated structural integrity with Δ BET = −6.3% after 40 cycles, while the nitro-functionalized MIL-101Cr exhibited a decrease in their BET surface of Δ BET = −25% and −20% for 3 and 4, respectively.

No abstract

No abstract

No abstract

No abstract