From CO2 Capture to Tuneable Optics and Surfactant Self-Assembly: Teaching Anilines New
Tricks
O. Alexander Bell,a Benjamin M. Mills,a Yaoyang Hu,a Yaozu Liaob and Charl FJ Faula*
a
School of Chemistry, University of Bristol, Bristol, UK
State Key Laboratory for Modification of Chemical Fibers and Polymer Materials & College of Materials
Science and Engineering, Donghua University, Shanghai, China
faulresearchgroup.com
b
Addressing the challenges facing current society requires creative use of techniques, materials and
approaches on the nanoscale and beyond. We have focussed efforts on anilines, looking beyond
their well-known conductive properties for solutions to a range of challenges facing the
nanosciences and wider society.1
Novel use of modern cross-coupling approaches2 to the synthesis of aniline-based materials allow
us to exploit the conjugated N-containing (and thus dopable) backbone structures as well as the
tuneable redox and optical properties. Applying such reactions for the formation of conjugated
microporous polymers provided routes to efficient and highly selective CO 2 capture,3a with
obvious environmental impact and applications. In addition, these materials are showing
exceptional I2 uptake properties,3b with >300 wt% uptake making them promising candidates for
application in nuclear waste management.
Using 2-photon polymerisation-based direct laser writing (DLW), finely controlled 3D-printed
conjugated structures can be prepared (see Figure 1).4 The ability to print redox-active
addressable periodic 3D structures enables the formation of actively tuneable photonic crystals.
We show that simple acid-base chemistry enables reversible switching of the refractive index of
such structures, with negligible corresponding dimensional change using DLW.
Figure 1. a) 3D-printed responsive photonic structure and b) 3-nm self-assembled nanowires in solution
In further efforts to utilise these functional aniline-based materials, we prepared an oligo(aniline)based cationic surfactant and investigated its supramolecular organisation into self-assembled
nanowires in solution.5 Using the dopable nature of these electroactive tail groups, we can now
actively tune their packing parameter, and thus the assembly of these novel electrostatic supraamphiphiles in a reversible fashion. We are currently also exploiting density functional theory
(DFT) calculations to provide detailed insight into the optoelectronic properties of our materials, 6
and thus enabling further design of species with attractive properties and function.
References:
1) C. F. J. Faul, Acc. Chem. Res. 2014, 47, 3428; 2a) Z. C. Shao et al., Chem. Eur. J. 2011, 17, 12512; b) C. U.
Udeh et al., J. Mater. Chem. 2011, 21, 18137; 3a) Y. Liao et al., Chem. Commun. 2014, 50, 8002; b) Y. Liao et
al., Macromolecules 2016, 49, 6322; 4) Y. Y. Hu et al., Adv. Opt. Mater. 2016, 4, DOI: 10.1002/adom.2016
00458; 5) O. A. Bell et al., J. Am. Chem. Soc. 2015, 137, 14288; B. M. Mills et al., Chem. Eur. J. 2016, 22,
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