Rotors, motors and switches in the solid state find a favorable playground in porous materials, such as Metal Organic Frameworks (MOFs), thanks to their large free volume, which allows for fast dynamics. We fabricated MOFs with reorientable linkers and benchmark mobility also at very low temperature, to reduce the energy demand for motion-activation and light stimulus-response. In particular, we have realized a fast molecular rotor in the solid state whose rotation speed approaches that of unhindered rotations in organic moieties even at very low temperatures (2 K). The rotors were hosted within the struts of a low-density porous crystalline MOF and energetically decoupled from their surroundings. A key point was the unusual crossed conformation adopted by the carboxylates around the pivotal bond on the rotor axle, generating geometrical frustration and very shallow wells along the circular trajectory. Continuos, unidirectional hyperfast rotation with an energy barrier of 6.2 cal/mol and a high frequency persistent for several turns is achieved (10 GHz below 2 K).[1] Responsive porous switchable framework materials endowed with light-responsive overcrowded olefins, took advantage of both the quantitative photoisomerization in the solid state and the porosity of the framework to reversibly modulate the gas adsorption in response to light. [2] Motors were inserted into metal-organic frameworks wherein two linkers with complementary absorption-emission properties were integrated into the same materials. Therefore, unidirectional motion was achieved by simple exposure to sun-light of the solid particles, which thus behave as autonomous nanodevices.[3] MOF nanocrystals comprising high-Z linking nodes interacting with the ionizing radiation, arranged in an orderly fashion at a nanometric distance from diphenylanthracene ligand emitters showed ultrafast sensitization of the ligand fluorescence, thus supporting the development of new engineered scintillators.[4] References 1. J. Perego, S. Bracco, M. Negroni, C. X. Bezuidenhout, G. Prando, P. Carretta, A. Comotti, P. Sozzani Nature Chem. 2020, 12, 845. 2. P. Sozzani, S. Bracco, S. J. Wezenberg, A. Comotti, B. L. Feringa Nature Chem. 2020, 12, 595. 3. W. Danowski, F. Castiglioni, A. Comotti, B. L. Feringa J. Am. Chem. Soc. 2020, 142, 9048. 4. J. Perego, F. Meinardi, S. Bracco, A. Comotti, A. Monguzzi Nature Photonics 2021, doi 10.1038/s41566-021-00769-z. Financial support from the Italian Ministry of University and Research (MIUR) through the grant ‘Dipartimenti di Eccellenza-2017 Materials For Energy’ is acknowledged. This research was funded by the PRIN-2015CTEBBA-003.

Comotti, A., Bracco, S., Perego, J., Bezuidenhout, C., Piva, S., Sozzani, P. (2021). Ultra-Fast Rotors and Light Emitting Ligands in Metal -Organic Frameworks. In Book of Abstracts (pp.630-630). 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND : Wiley-Blackwell Publishing, Inc..

Ultra-Fast Rotors and Light Emitting Ligands in Metal -Organic Frameworks

Comotti, Angiolina
Primo
;
Bracco, Silvia;Perego, Jacopo;Bezuidenhout, Charl X.;Sozzani, Piero
2021

Abstract

Rotors, motors and switches in the solid state find a favorable playground in porous materials, such as Metal Organic Frameworks (MOFs), thanks to their large free volume, which allows for fast dynamics. We fabricated MOFs with reorientable linkers and benchmark mobility also at very low temperature, to reduce the energy demand for motion-activation and light stimulus-response. In particular, we have realized a fast molecular rotor in the solid state whose rotation speed approaches that of unhindered rotations in organic moieties even at very low temperatures (2 K). The rotors were hosted within the struts of a low-density porous crystalline MOF and energetically decoupled from their surroundings. A key point was the unusual crossed conformation adopted by the carboxylates around the pivotal bond on the rotor axle, generating geometrical frustration and very shallow wells along the circular trajectory. Continuos, unidirectional hyperfast rotation with an energy barrier of 6.2 cal/mol and a high frequency persistent for several turns is achieved (10 GHz below 2 K).[1] Responsive porous switchable framework materials endowed with light-responsive overcrowded olefins, took advantage of both the quantitative photoisomerization in the solid state and the porosity of the framework to reversibly modulate the gas adsorption in response to light. [2] Motors were inserted into metal-organic frameworks wherein two linkers with complementary absorption-emission properties were integrated into the same materials. Therefore, unidirectional motion was achieved by simple exposure to sun-light of the solid particles, which thus behave as autonomous nanodevices.[3] MOF nanocrystals comprising high-Z linking nodes interacting with the ionizing radiation, arranged in an orderly fashion at a nanometric distance from diphenylanthracene ligand emitters showed ultrafast sensitization of the ligand fluorescence, thus supporting the development of new engineered scintillators.[4] References 1. J. Perego, S. Bracco, M. Negroni, C. X. Bezuidenhout, G. Prando, P. Carretta, A. Comotti, P. Sozzani Nature Chem. 2020, 12, 845. 2. P. Sozzani, S. Bracco, S. J. Wezenberg, A. Comotti, B. L. Feringa Nature Chem. 2020, 12, 595. 3. W. Danowski, F. Castiglioni, A. Comotti, B. L. Feringa J. Am. Chem. Soc. 2020, 142, 9048. 4. J. Perego, F. Meinardi, S. Bracco, A. Comotti, A. Monguzzi Nature Photonics 2021, doi 10.1038/s41566-021-00769-z. Financial support from the Italian Ministry of University and Research (MIUR) through the grant ‘Dipartimenti di Eccellenza-2017 Materials For Energy’ is acknowledged. This research was funded by the PRIN-2015CTEBBA-003.
abstract + slide
Molecular rotors, porous materials, MOFs, ultra-fast dynamics,scintillators
English
25th IUCr Congress (14-22 August 2021)
2021
Book of Abstracts
2021
77
Supplement
630
630
MS-100-3
none
Comotti, A., Bracco, S., Perego, J., Bezuidenhout, C., Piva, S., Sozzani, P. (2021). Ultra-Fast Rotors and Light Emitting Ligands in Metal -Organic Frameworks. In Book of Abstracts (pp.630-630). 2 ABBEY SQ, CHESTER, CH1 2HU, ENGLAND : Wiley-Blackwell Publishing, Inc..
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/339042
Citazioni
  • Scopus ND
  • ???jsp.display-item.citation.isi??? 0
Social impact