Au alloying into Pd can greatly improve the catalytic activity for FA dehydrogenation. Distinct PdAu surface ensembles are prepared and the Au alloying effects are revealed by experimental and theoretical examinations.

We compared four types of ZIF-8 with varying sizes and shapes to determine their thermal-structural stability and derive appropriate thermal activation conditions and correlation between structural characteristics and adsorption properties. Under air, the ZIF-8 phase for all the samples was converted completely into the zinc oxide phase above ∼300°C, though thermalgravimetric analysis (TGA) indicated that the original structure was stable to ∼300−350°C. Longer exposures (∼30 d) suggested that thermal activation at ∼200°C was appropriate for the removal of guest and/or solvent molecules under air without structural damage. Despite no noticeable change in X-ray diffraction (XRD) patterns after activation at 250°C under air, the resulting BET surface areas and CO 2 adsorption amounts (at 1 bar and 30°C) of ZIF-8s were reduced to ∼44−54 and ∼72−87%, respectively, as compared to those of appropriately activated ZIF-8s. It appears that after the activation at 250°C under air, some Zn and N atoms were dissociated and converted to ZnOH and NOH, respectively, causing the partial structural damage of ZIF-8s.

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