24. November 2016
Multi-colored dye sensitization of organic photovoltaics
Front Cover in Journal of Materials Chemistry A
During the last 10 years organic photovoltaics (OPVs) has evolved from an early research effort to a major research field and tremendous progress has been made in the synthesis and production of organic solar cells. Compared to inorganic solar cells, organic photovoltaics offer many advantages, such as low cost, high throughput production, flexible devices, lightweight products, and custom colors. On the down side, OPVs still have significantly lower efficiency values and lifetime expectations compared to their inorganic counterparts.
To improve device performance, different strategies have to be developed in parallel. During the last few years, Dr. Tayebeh Ameri and EAM Member Prof. Christoph J Brabec from the Institute of Materials for Electronics and Energy
Technology (i-Meet) have centered their research on an elegant alternative approach to overcoming the photocurrent and the performance limitations of polymer- fullerene solar cells in a simple single-junction structure by implementing a sensitizer with a complementary absorption profile into the host matrix.
To boost near infrared light harvesting, they have investigated different semiconductor systems such as low bandgap polymers, small molecules, dye compounds, and hybrid and inorganic nanoparticles/nanostructures. They have also engineered multi-composites to ensure spectrally broad absorption, to maximize open circuit voltages and to reduce parasitic loss mechanisms like non-radiative recombination.
Recently, in collaboration with Prof. Rik Tykwinski, formerly Department of Chemistry and Pharmacy at FAU, they have synthesized and fully-characterized the novel dye compounds of silicon naphthalocyanine and silicon phthalocyanine with axial substituents consisting of pyrene acid groups. By incorporating these novel compounds into the P3HT/PCBM matrix a strong photosensitivity in the near-IR region up to 950 nm and, consequently,significant performance improvement of over 30% compared to the host reference was achieved. Their results illustrate the potential of the multi-colored dye sensitization concept as a powerful approach to mitigate the non-ideal optical absorption normally encountered in organic-based optoelectronic
Panchromatic ternary/quaternary polymer/fullerene BHJ solar cells based on novel silicon naphthalocyanine and silicon phthalocyanine dye sensitizers
Research Areas B, A2
L. Ke, N. Gasparini, J. Min, H. Zhang, M. Adam, S. Fladischer, K. Forberich, C. Zhang, E. Spiecker, R. R. Tykwinski, C. J. Brabec, T. Ameri
J. Mater. Chem. A, 2017, 5, 2550 – 2562