Dr. Verena Engelhardt

Dye-sensitized solar cells have emerged as credible alternatives to conventional solid-state junction devices during the last years. The absorption profile as well as the electronic properties of the organic dyes greatly influence the efficiency of such organic solar cells. Phthalocyanine-type dyes such as porphyrazines show intense absorptions around 400 nm (B band) and 700 nm (Q band), with little absorptivity in between.  Hence, hybrids of porphyrazines with covalently linked dyes that absorb between 500 – 600 nm would maximize the absorption in the visible and could improve the efficiency of the light-harvesting systems at the core of dye-sensitized solar cells.

The ease with which peripheral substituents can be implemented around a central porphyrazine scaffold prompted us to explore synthetic routes to alkynyl-linked multichromophore ensembles. Among the systems investigated by our former co-worker Dr. J. Fleischhauer, are xanthene-, and rhodamine-porphyrazine hybrids.

At the focus of my work is a porphyrazine peripherally substituted by eight Bodipy (boron dipyrromethene) units (1). Bodipy dyes, which are widely used as fluorescent biomarkers, have a good synthetic accessibility and absorb visible light around 500 nm.

„Bodipy-Porphyrazine-Hybrids for Dye-sensitized solar cells“  Verena Engelhardt, CINSAT Frühjahrskolloquium 2012, 24.02.2012 Friedrichroda.

Verena Engelhardt, Rüdiger Faust
"Bodipy-Porphyrazine Hybrids as Dyes for Photovoltaic Devices", 3rd EuCheMS Chemistry Congress Nürnberg 2010, August 29-September 02, 2010, Abstract VIIa.046.

Verena Engelhardt, Susanne Kuhri, Dirk M. Guldi, Rüdiger Faust
“Bodipy-Porphyrazine Hybrids for Dye-sensitized solar cells”, 7^th International Conference on Porphyrins and Phthalocyanines (ICPP), Jeju Korea 2012, Juli 01-06, 2012, Abstract S13-066.

Verena Engelhardt, Susanne Kuhri, Dirk M. Guldi, Rüdiger Faust
“Bodipy-Porphyrazine Hybrids for Dye-sensitized solar cells”, ORCHEM 2012, 18^th Lecture Conference Liebig Vereinigung für Organische Chemie, Weimar, September 2012.

Verena Engelhardt, Rüdiger Faust
“Unsymmetrical BODIPY-Porphyrazine Conjugates with Panchromatic Light Harvesting and Tripodal Surface Anchoring Groups”, 8th International Conference on Porphyrins and Phthalocyanines (ICPP-8), Istanbul, Juni 22-27, 2014, Abstract S06-014.

Verena Engelhardt, Rüdiger Faust
“Unsymmetrical BODIPY-Porphyrazine Conjugates with Panchromatic Light Harvesting and Tripodal Surface Anchoring Groups”, ORCHEM 2014, 19^th Lecture Conference Liebig Vereinigung für Organische Chemie, Weimar, September 15-17, 2014.

Verena Engelhardt, Rüdiger Faust
“Unsymmetrical BODIPY-Porphyrazine Conjugates with Panchromatic Light Harvesting and Tripodal Surface Anchoring Groups”, CINSAT Herbstkolloquium, Kassel, Oktober 15, 2014.

B. Wang, V. Engelhardt, A. Roth, G. Katsukis, L. Wibmer, M. Volland, K. Brunner, R. Faust, D. M. Guldi
“Graphite exfoliation and nanohybrid formation with porphyrazine-pyrene conjugates”, 3^rd Erlangen Symposium on Synthetic Carbon Allotropes, Oktober 04-07, 2015.

Verena Engelhardt, Rüdiger Faust
“BODIPY-Porphyrazines with Panchromatic Light Harvesting for Dye-sensitized Solar Cells”, CINSAT Frühjahrskolloquium, Friedrichroda, Februar 25-26, 2016.

Verena Engelhardt, Rüdiger Faust
“Influence of peripheral BODIPY-Substituents on the Solar Cell Performance of Porphyrazines”, 9th International Conference on Porphyrins and Phthalocyanines (ICPP-9), Nanjing China, Juli 03-08, 2016, Abstract S34-P-001. 

Verena Engelhardt, Bingzhe Wang, Dirk M. Guldi, Rüdiger Faust
“Tetrapyrazinoporphyrazines as Photoelectron-Acceptors in noncovalent Assemblies to Graphene”, 9th International Conference on Porphyrins and Phthalocyanines (ICPP-9), Nanjing China, Juli 03-08, 2016, Abstract S31-P-002.

N- versus p-doping of graphite: What drives its wet-chemical exfoliation?, B. Wang, V. Engelhardt, A. Roth, R. Faust, D. M. Guldi, Nanoscale 2017, online.
DOI: 10.1039/c7nr03379f

En route towards panchromatic light harvesting: photophysical and electrochemical properties of Bodipy–porphyrazine conjugates. S. Kuhri, V. Engelhardt, R. Faust and D. M. Guldi, Chem. Sci. 2014, 5, 2580-2588.
DOI: 10.1039/c4sc00326h

Light-harvesting with panchromatically absorbing BODIPY-porphyrazine conjugates to power electron transfer in supramolecular donor-acceptor ensembles. V. Engelhardt, S. Kuhri, J. Fleischhauer, M. Garcia-Iglesias, D. Gonzalez-Rodriguez, G. Bottari, T. Torres, D. M. Guldi, R. Faust, Chem. Sci. 2013, 4, 3888-3893.
DOI: 10.1039/C3SC51622A

The Cobalt-Way to Heterophenylenes: Syntheses of 2-Thianorbiphenylenes, Monoaza-biphenylenes, and Linear 1-Aza[3]phenylene {Biphenyleno[2,3-a]cyclobuta[1,2-b]pyridine}. V. Engelhardt, J. G. Garcia, A. A. Hubaud, K. A. Lyssenko, S. Spyroudis, T. V. Timofeeva, P. Tongwa, K. P. C. Vollhardt, Synlett 2011, 2, 280-284.
DOI: 10.1055/s-0030-1259087