Naslov
Variable-temperature in situ powder X-ray diffraction monitoring of mechanosynthesis of metal-organic frameworks

Autori
Užarević, Krunoslav ; Halasz, Ivan ; Motillo, Cristina ; Julien, Patrick ; Puškarić, Andreas ; Štrukil, Vjekoslav ; Friščić, Tomislav

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
250th American Chemical Society National Meeting & Exposition

Mjesto i datum
Boston (MA), Sjedinjene Američke Države, 16.08.2015. - 20.08.2015

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Nije recenziran

Ključne riječi
Mechanochemistry; in situ methods; synchrotron PXRD monitoring; MOF materials

Sažetak
Despite wide applications and industrial importance, mechanisms of mechanochemical reactions remain largely unknown. Poor understanding of such reactivity is illustrated by almost complete lack of knowledge of how external temperature influences milling reactions. While thermal monitoring of very exothermic reactions (mechanochemical self- sustained reactions)1 led to models of mechanochemical reactivity for inorganic materials, the effect of temperature on reactivity of softer materials (pharmaceutical cocrystals, metal-organic frameworks) is unknown. Indeed, the first in situ, real-time observation of milling reactions was made possible only recently, through synchrotron X-ray diffraction2- 3 or Raman spectroscopy.4 We now present the first variable-temperature in situ X-ray diffraction study of mechanochemical assembly of metal-organic frameworks, including microporous MOF-74. Reactions were monitored in custom-designed equipment, permitting simultaneous variation of temperature and X-ray diffraction study of the milled reaction mixture. The observed sensitivity of mechanochemical reactivity to temperature is unexpectedly high, with only slight changes in temperature having a significant effect on reaction rates and mechanism. These results, we believe, provide a fresh and unexpected view of temperature in the context of mechanochemical reactivity. [1] Takacs, Faraday Discuss. 2014, 170, 251. [2] Friščić et al., Nature Chem. 2013, 5, 66 ; [3] Halasz et al., Nat. Prot. 2013, 8, 1718. [4] Gracin et al, Angew. Chem. Int. Ed. 2014, 53, 6193.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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