| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Composites for Energy Applications: Materials for Renewable Energy Applications 2022
|
| Presentation Title |
Spectroscopic Investigation of the Electronic and Excited State Properties of Para-substituted Tetraphenyl Porphyrins and Their Electrochemically Generated Ions |
| Author(s) |
Lauren Hanna, Joseph A. Teprovich, Patrick A. Ward |
| On-Site Speaker (Planned) |
Lauren Hanna |
| Abstract Scope |
Porphyrins play pivotal roles in many crucial biological processes including photosynthesis. Electrochemical and spectroscopic signatures reveal that minor substitutions on the macrocycle may significantly alter the electronic and excited state dynamics of this class of complexes. To obtain a deeper insight into the influences of porphyrin functionalization, four free-base, meso-substituted porphyrins were investigated and the influence of various substituents, (-hydroxy,-carboxy, and -nitro) in the para position of the meso-substituted phenyl moieties were evaluated. The spectral features observed among the various porphyrins were further explained using rendered frontier molecular orbitals pertaining to the relevant transitions. Electrochemically generated anionic and cationic porphyrin species, formed via in-situ spectroelectrochemistry, yield additional electronic information as a function of the nature of the substituent. Excited state properties were revealed through femtosecond transient absorption spectroscopy analysis, in which, global analysis extracted various lifetime details suggesting differing relaxation dynamics among the porphyrins. Herein, this focuses on an in-depth and comprehensive analysis of the electronic and excited state effects associated with systematically varying the induced dipole at the methine bridge of the free-base porphyrin macrocycle and the spectroscopic signatures related to the neutral, anionic, and cationic species of these porphyrins. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Energy Conversion and Storage, Electronic Materials, Other |