A. Jean-Luc Ayitou
Research in the AJA Laboratory is strongly interdisciplinary…crossing disciplines and blending conventional organic synthesis techniques and photophysical & photochemical paradigms to devise alternatives approaches for energy applications, organic materials, and sustainable chemical synthesis. While the AJA group research themes are inspired by fundamental and established concepts in organic photochemistry and photophysics, the use of cutting edge techniques and instrumentations to rationalize molecular interactions and transformations is paramount; for example, we aim at designing new non-classical aromatic organic chromophores/materials (fig. 1) for light-harvesting applications, biomedical protocols, and solar energy conversion.
Synthesis and Photophysical Characterization of Novel Organic Dyes
Synthesis of non-classical aromatic triplet chromophores/materials for light harvesting and modulation: Application in energy upconversion, photodynamic therapy, solar cells & fuels, and batteries.
Non-classical aromatic chromophores are novel triplet dyes, which upon absorption of light energy, can easily populate their triplet excited state thanks to aromaticity reversal. We aim to use our dyes as light-harvesting materials in a number of applications viz. triplet sensitization, solar cells, photocatalysis, and batteries.
Chromophore interactions in the solid-state and/or photonic devices
Using advanced spectroscopy tools, we investigate energy/exciton transfer in organic solid or organic-semiconductor materials. Photo-excitation of the new class of organic chromophores developed in our lab would create excitons that migrate or diffuse through solid (ordered) materials via specific mechanisms. In this picture, we aim at elucidating the dynamic/kinetic of the energy/exciton migration; we also envision understanding how molecular/chromophore•••chromophore interactions would dictate the macroscopic photo-behavior of the materials of our interest (Fig. 2).
Figure 2: Dynamic/kinetic of energy transfer in light-harvesting donor-acceptor materials.
We are currently developing new organic polymeric materials, which can be used as “vehicle” in a synergistic/controlled release of valuable chemicals, signaling agents or other therapeutics. Using the established photochemical paradigms of the molecular building blocks, we will investigate how molecular interactions will dictate the photochemistry of the macroscopic materials.
Outreach and Science-Community Advocate
In our effort to promote diversity and a better/broader understanding of socio-cultural relevance to the Chemical Sciences, the AJA lab has initiated the following outreach program: VISCUS = Vivifying Scientific Curiosity for Underrepresented Undergraduate (URM) Students. Through this program, URM students are trained to use advanced spectroscopy tools to investigate common photochemical processes, which one might encounter in Nature.
1) Young Ju Yun, Nareshbabu Kamatham, Manoj K. Manna, Jingbai Li, Gary P. Wiederrecht, David J. Gosztola, Andrey Yu. Rogachev, and A. Jean-Luc Ayitou*, Interplay Between Energy & Charge Transfers in a Polyaromatic Triplet Donor–Acceptor Dyad, J. Phys. Chem. C 2020, doi: 10.1021/acs.jpcc.0c01530. (link)
2) Nareshbabu Kamatham, Jingbai Li, Siamak Shokri, Guang Yang, Andrey Yu. Rogachev and Jean-Luc Ayitou*; Quinoidization of Polyacene Diimides: Photophysics, Aromaticity, and Stability of the Novel Quinoidal Acenes,Eur. J. Org. Chem., 2020, doi:10.1002/ejoc.201901456. (link) (Cover Page)
3) Lipinska, Kris; Cavallo, Francesca; Ayitou, A. J.-L. and Segre, Carlo; Quencher-Free Enhanced Emission in Cluster-Free Er-doped Heavy Metal Oxide Glasses; Mat. Exp., 2019, 9 (3), 1072–1084. (link)
4) Manna, K. M.; Shokri, S.; Wiederrecht, G. P.; Gosztola, D. J. and Ayitou, A. J.-L.*; New Perpectives for Triplet-Triplet Annihilation Photo Upconversion Using All-Organic Donors and Acceptors Chromophores; Commun., 2018, 54, 5809–5818. (link)
5) Shokri, S.; Li, J.; Wiederrecht, G. P.; Gosztola, D. J.; Ugrinov, A.; Jockush, S.; Rogachev, A. Y. and Ayitou, A. J.-L.* A Naphtho-p-quinodimethane Exhibiting Baird’s Anti-Aromaticity, Broken Symmetry and Attractive Photoluminescence. Org. Chem., 2017, 82, 10167–10173. (link)
6) Shokri, S.; Wiederrecht, G. P.; Gosztola, D. J. and Ayitou, A. J.-L.* Photon Upconversion Using Baird-Type Anti-Aromatic Quinoidal Naphthalene Derivative as a Sensitizer, Phys. Chem. C, 2017,121, 23377–23382. (link)
• B.S., North Dakota State University (advisor: Sivaguru Jayaraman), 2008
• Ph.D., North Dakota State University (advisor: Sivaguru Jayaraman), 2013
• Postdoctoral Fellow, University of California Los Angeles (advisors: Miguel Garcia-Garibay), 20013-2016.