Solution-processed and high-performance organic solar cells using small molecules with a benzodithiophene unit.

Three small molecules named DR3TBDTT, DR3TBDTT-HD, and DR3TBD2T with a benzo[1,2-b:4,5-b']dithiophene (BDT) unit as the central building block have been designed and synthesized for solution-processed bulk-heterojunction solar cells. Power conversion efficiencies (PCEs) of 8.12% (certified 7.61%) and 8.02% under AM 1.5G irradiation (100 mW cm(-2)) have been achieved for DR3TBDTT- and DR3TBDT2T-based organic photovoltaic devices (OPVs) with PC71BM as the acceptor, respectively. The better PCEs were achieved by improving the short-circuit current density without sacrificing the high open-circuit voltage and fill factor through the strategy of incorporating the advantages of both conventional small molecules and polymers for OPVs.

[1]  Yong Cao,et al.  Simultaneous Enhancement of Open‐Circuit Voltage, Short‐Circuit Current Density, and Fill Factor in Polymer Solar Cells , 2011, Advanced materials.

[2]  Yongsheng Chen,et al.  A Planar Small Molecule with Dithienosilole Core for High Efficiency Solution-Processed Organic Photovoltaic Cells , 2011 .

[3]  Yuan Zhang,et al.  A modular molecular framework for utility in small-molecule solution-processed organic photovoltaic devices , 2011 .

[4]  Thuc-Quyen Nguyen,et al.  Nanoscale Phase Separation and High Photovoltaic Efficiency in Solution‐Processed, Small‐Molecule Bulk Heterojunction Solar Cells , 2009 .

[5]  Yongsheng Chen,et al.  Efficient small molecule bulk heterojunction solar cells with high fill factors via introduction of π-stacking moieties as end group , 2013 .

[6]  Alan J. Heeger,et al.  Intensity dependence of current-voltage characteristics and recombination in high-efficiency solution-processed small-molecule solar cells. , 2013, ACS nano.

[7]  Thomas Cauchy,et al.  Manipulation of the Open‐Circuit Voltage of Organic Solar Cells by Desymmetrization of the Structure of Acceptor–Donor–Acceptor Molecules , 2011 .

[8]  Matthias Weil,et al.  Correlation of π-conjugated oligomer structure with film morphology and organic solar cell performance. , 2012, Journal of the American Chemical Society.

[9]  Yang Yang,et al.  Spin‐Coated Small Molecules for High Performance Solar Cells , 2011 .

[10]  Feng Xu,et al.  Replacing alkoxy groups with alkylthienyl groups: a feasible approach to improve the properties of photovoltaic polymers. , 2011, Angewandte Chemie.

[11]  Yongsheng Chen,et al.  Small molecules based on benzo[1,2-b:4,5-b']dithiophene unit for high-performance solution-processed organic solar cells. , 2012, Journal of the American Chemical Society.

[12]  M. Stefan,et al.  Donor–Acceptor Semiconducting Polymers Containing Benzodithiophene with Bithienyl Substituents , 2012 .

[13]  W. Li,et al.  Donor-acceptor conjugated polymer based on naphtho[1,2-c:5,6-c]bis[1,2,5]thiadiazole for high-performance polymer solar cells. , 2011, Journal of the American Chemical Society.

[14]  Chain‐Shu Hsu,et al.  Synthesis of conjugated polymers for organic solar cell applications. , 2009, Chemical reviews.

[15]  Yang Yang,et al.  Tandem polymer solar cells featuring a spectrally matched low-bandgap polymer , 2012, Nature Photonics.

[16]  Miao Xu,et al.  Enhanced power-conversion efficiency in polymer solar cells using an inverted device structure , 2012, Nature Photonics.

[17]  Jie Zhang,et al.  Efficient Solution‐Processed Small‐Molecule Solar Cells with Inverted Structure , 2013, Advanced materials.

[18]  Thuc-Quyen Nguyen,et al.  Small Molecule Solution-Processed Bulk Heterojunction Solar Cells† , 2011 .

[19]  Yongsheng Chen,et al.  Impact of dye end groups on acceptor-donor-acceptor type molecules for solution-processed photovoltaic cells† , 2012 .

[20]  Yongsheng Chen,et al.  Solution Processable Rhodanine‐Based Small Molecule Organic Photovoltaic Cells with a Power Conversion Efficiency of 6.1% , 2012 .

[21]  Wei You,et al.  Quantitatively Analyzing the Influence of Side Chains on Photovoltaic Properties of Polymer−Fullerene Solar Cells , 2010 .

[22]  Peter Bäuerle,et al.  Small molecule organic semiconductors on the move: promises for future solar energy technology. , 2012, Angewandte Chemie.

[23]  Yongfang Li,et al.  Small molecule semiconductors for high-efficiency organic photovoltaics. , 2012, Chemical Society reviews.

[24]  J. Shim,et al.  Polydimethylsiloxane as a macromolecular additive for enhanced performance of molecular bulk heterojunction organic solar cells. , 2011, ACS applied materials & interfaces.

[25]  Wei Lin Leong,et al.  Solution-processed small-molecule solar cells with 6.7% efficiency. , 2011, Nature materials.