10.1021/acs.cgd.7b00910.s001
Jie Ma
Jie
Ma
Zhi-Zhou Li
Zhi-Zhou
Li
Xue-Dong Wang
Xue-Dong
Wang
Liang-Sheng Liao
Liang-Sheng
Liao
Molecular-Oriented Self-Assembly of Small Organic
Molecules into Uniform Microspheres
American Chemical Society
2017
microsphere
DCM
Uniform Microspheres Self-assembly
Small Organic Molecules
kcal
optoelectronic
rhombic microcrystals
π-
exhibits amphiphilic nature
DFPHP
hydrogen bonds
ethanol molecules
DFHP
fabrication
2017-08-23 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Molecular-Oriented_Self-Assembly_of_Small_Organic_Molecules_into_Uniform_Microspheres/5341600
Self-assembly
of small organic π-conjugated molecules into
micro- and nanostructures has drawn much attention because of their
wide applications in miniature optoelectronic devices. Many efforts
have been focused on the controlled fabrication of organic micro/nanostructures,
which are determined by various factors including kinetic and thermodynamic
process but still remain poorly understood. In our research, two π-conjugated
molecules of (<i>E</i>)-3-(4-(diphenylamino)phenyl)-1-(4-fluoro-2-hydroxyphenyl)prop-2-en-1-one
(DFHP) and (<i>E</i>)-3-(4-(bis(4-methoxyphenyl)amino)phenyl)-1-(4-fluoro-2-hydroxyphenyl)prop-2-en-1-one
(DFPHP) with a small difference of substituent groups were designed
and synthesized. By the solution-exchange method, DFHP are self-assembled
into amorphous microspheres while DFPHP tend to grow into crystalline
rhombic microcrystals. The head of DFHP organic molecules can form
hydrogen bonds with ethanol molecules and the tail of DFHP dissolves
in the dichloromethane (DCM) phase, which exhibits amphiphilic nature,
contributing to the self-assembly of microspheres. In a contrast,
both the head and the tail of DFPHP can have hydrogen bonds with the
ethanol molecules, which leads to the ordered DFPHP molecular packing
and then the formation of rhombic microcrystals. Furthermore, based
on simulated growth/equilibrium morphology, DFHP form the amorphous
microspheres other than the crystalline microcrystals due to the lower
attachment energy (<i>E</i><sub>total</sub> = −43.5
kcal/mol) as compared with that (<i>E</i><sub>total</sub> = −53.1 kcal/mol) of DFPHP. Our demonstration can indeed
builds the structure–morphology relationship for rational fabrication
of organic micro/nanostructures, which would contribute to integrated
optoelectronics.