ELECTRICAL CHARACTERIZATION OF P3HT/PCBM BULK HETEROJUNCTION ORGANIC SOLAR CELL

Photovoltaic performance of bulk heterojunction organic solar cell based on poly (3-hexylthiophene) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM) were investigated. The active layer is a spin coated organic blend of a p material (P3HT) and an n-material from the fullerene derivative PCBM; it is sandwiched between electrodes ITO-PEDOT/PSS and Al/LiF as back-contact. Modeling of organic bulk heterojunction solar cells is complicated because of various internal mechanisms involved. Two models have been suggested, namely an effective medium model and a network model. We applied an effective medium model where the main assumption is the p–n nanostructure is treated as one single effective semiconductor layer, and parameters in this configuration are fed into a standard solar cell device simulator, called SCAPS. In this model, other non-carrier related properties, such as the refractive index n, the dielectric constant ε and the absorption constant α are influenced by both p–n materials and used as input parameters. The power conversion efficiency of 3.88% with short circuit current density of 20.61 mA/cm2, open circuit voltage of 0.39 V and fill factor of 48% were obtained. Finally, factors which could limit cell conversion efficiency are discussed.

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Derivation and solution of effective medium equations for bulk heterojunction organic solar cells

European Journal of Applied Mathematics ◽

10.1017/s0956792516000541 ◽

2017 ◽

Vol 28 (6) ◽

pp. 973-1014 ◽

Cited By ~ 6

Author(s):

G. RICHARDSON ◽

C. P. PLEASE ◽

V. STYLES

Keyword(s):

Organic Solar Cells ◽

Bulk Heterojunction ◽

Effective Medium ◽

Hole Transport ◽

Bulk Heterojunctions ◽

Micro Structure ◽

Electron Hole ◽

Effective Medium Model ◽

Medium Model ◽

Current Voltage Curve

A drift-diffusion model for charge transport in an organic bulk heterojunction solar cell, formed by conjoined acceptor and donor materials sandwiched between two electrodes, is formulated. The model accounts for (i) bulk photogeneration of excitons, (ii) exciton drift and recombination, (iii) exciton dissociation (into polarons) on the acceptor–donor interface, (iv) polaron recombination, (v) polaron dissociation into a free electron (in the acceptor) and a hole (in the donor), (vi) electron/hole transport and (vii) electron–hole recombination on the acceptor–donor interface. A finite element method is employed to solve the model in a cell with a highly convoluted acceptor/donor interface. The solutions show that, with physically realistic parameters, and in the power generating regime, the solution varies little on the scale of the micro-structure. This motivates us to homogenise over the micro-structure; a process that yields a far simpler one-dimensional effective medium model on the cell scale. The comparison between the solution of the full model and the effective medium (homogenised) model is very favourable for applied voltages less than the built-in voltage (the power generating regime) but breaks down as the applied voltages increases above it. Furthermore, it is noted that the homogenisation technique provides a systematic way to relate effective medium modelling of bulk heterojunctions [19, 25, 36, 37, 42, 59] to a more fundamental approach that explicitly models the full micro-structure [8, 38, 39, 58] and that it allows the parameters in the effective medium model to be derived in terms of the geometry of the micro-structure. Finally, the effective medium model is used to investigate the effects of modifying the micro-structure geometry, of a device with an interdigitated acceptor/donor interface, on its current–voltage curve.

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Plasmon enhanced power conversion efficiency in inverted bulk heterojunction organic solar cell

Organic, Hybrid, and Perovskite Photovoltaics XVIII ◽

10.1117/12.2273610 ◽

2017 ◽

Author(s):

Minu Mohan ◽

Ramkumar Sekar ◽

Manoj A. G. Namboothiry

Keyword(s):

Solar Cell ◽

Power Conversion Efficiency ◽

Conversion Efficiency ◽

Organic Solar Cell ◽

Bulk Heterojunction ◽

Power Conversion

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Investigation of Recombination Process of P3HT: PCBM Organic Solar Cell

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.1147 ◽

2012 ◽

Vol 622-623 ◽

pp. 1147-1151

Author(s):

E.K. Chiew ◽

Muhammad Yahaya ◽

A.P. Othman

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Organic Solar Cells ◽

Bulk Heterojunction ◽

Computational Study ◽

Experimental Result ◽

Semiconductor Layer ◽

Recombination Mechanism ◽

Effective Medium Model ◽

Cell Capacitance

We applied an effective medium model for a computational study and investigated a recombination mechanism in a P3HT:PCBM bulk heterojunction (BHJ) organic solar cells where the main assumption is the p-n nanostructure is treated as one single effective semiconductor layer, and parameters in this configuration are fed into a standard solar cell device simulator, called a Solar Cell Capacitance Simulator (SCAPS). Using SCAPS, the electrical performances of organic solar cells and the intensity-dependent current density -voltage (J-V) were simulated and compared with the actual experimental result. The results show that they are in good agreement with each other and monomolecular recombination mechanism is the dominant mechanism in the BHJ organic solar cells.

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