Low-bandgap push–pull molecules in polymer matrices for use in thin-film organic photovoltaic devices

Conjugated polymers are widely used in thin-film organic photovoltaic devices to absorb light and serve as electron donors or acceptors. Small molecular analogues are attractive substitutes because they have fully defined structures, can be purified rigorously, and are typically more soluble and volatile. However, producing active films composed primarily of small molecules remains challenging. We have devised bulk heterojunction solar cells in which poly(3-hexylthiophene-2,5-diyl) and poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] are used as matrices to prepare films containing low-bandgap push–pull molecules as electron donors and (6,6)-phenyl-C61-butyric acid methyl ester or (6,6)-phenyl-C71-butyric acid methyl ester as electron acceptors. Compared with reference devices devoid of push–pull molecular additives, increases in power conversion efficiencies up to 30.4% were measured.

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Electrospun photonics topography for organic photovoltaics

MRS Proceedings ◽

10.1557/opl.2014.726 ◽

2014 ◽

Vol 1671 ◽

Cited By ~ 2

Author(s):

Khadija Kanwal Khanum ◽

Praveen C. Ramamurthy

Keyword(s):

Methyl Ester ◽

Acid Methyl Ester ◽

Processing Parameters ◽

Single Step ◽

Organic Photovoltaic ◽

Photovoltaic Devices ◽

Organic Photovoltaic Devices ◽

Acid Methyl ◽

Reflection Of Light ◽

Butyric Acid Methyl Ester

ABSTRACTA Photonics device requires uniform periodic structural arrangement. Various techniques have been used to fabricate these types of structures, which employs several steps of fabrication. This work proposes single step hierarchical array of equal submicron size porous structure fabricated through tuning electrospinning processing parameters. The dictating parameters were high voltage, tip to collector distance and solvent used on the evolving structure. Morphological and optical investigations suggested the uniform periodic topography and enhancement in light absorption, which is assumed due to internal reflection of light. This structure was evaluated for better light harvesting as active layer in organic photovoltaic devices using poly (3 hexyl thiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) blend, and further studying enhancement in photoelectrical characteristics.

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The Promotion of the Efficiency of Organic Photovoltaic Devices by Addition of Anisotropic CdSe Nanocrystals

International Journal of Photoenergy ◽

10.1155/2014/219123 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8

Author(s):

Shu-Ru Chung ◽

Hong-Shuo Chen ◽

Chen-Yu Chien ◽

Meng-Yi Bai ◽

Kuan-Wen Wang

Keyword(s):

Active Layer ◽

Acid Methyl Ester ◽

Organic Photovoltaic ◽

Cdse Nanocrystals ◽

Photovoltaic Devices ◽

Organic Photovoltaic Devices ◽

Acid Methyl ◽

Seed Growth ◽

Growth Method ◽

Butyric Acid Methyl Ester

CdSe nanocrystals (NCs) with different morphologies have been synthesized and applied as the acceptor in the active layer of the organic photovoltaic (OPV) devices. CdSe tetrapod (TP)/nanorod (NR) with zinc-blended seeds and wurtzite arms is prepared by seed growth method and mixed with poly(3-hexylthiophene) (P3HT): [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). When the concentrations of CdSe in P3HT: PCBM system are 50 wt% optimally, the efficiency can be promoted about 4.3%, suggesting that an enhancement of 13.2% can be obtained and the addition of anisotropic CdSe NCs content in the active layer can be beneficial for the transport of electrons and light absorption in the OPV devices.

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