p-i-n like behavior in three-layered organic solar cells having a co-deposited interlayer of pigments

Abstract

Three-layered organic solar cells, having a sandwiched interlayer of co-deposited p-type phthalocyanine (Pc) pigments and n-type perylene derivative (PTC) pigments, exhibited photocurrent enhancement when compared with two-layered cells without the interlayer. A large number of Pc/PTC molecular contacts within the interlayer serve as active sites for effective charge carrier photogeneration. The photovoltaic characteristics of the three-layered configuration suggest the formation of a p-i-n like structure, in which the built-in potential produced by Fermi level differences in the respective pigment layers is mainly distributed across the co-deposited interlayer. Inorganic semiconductor films are also shown to be applicable to the present p-i-n cell structure as an n layer to obtain larger photovoltages.

pn-control and pn-homojunction formation of metal-free phthalocyanine by doping

“…[1][2][3][4][5][6][7][8] Based on experience with inorganic solar cells, to create a built-in potential, pn-control of highly purified organic semiconductors by doping 9, 10 is required. 11 For single C 60 films, we have reported complete pn-control 12 and pn-homojunction formation.…”

Bandgap Science for Organic Solar Cells

“…In order to overcome this contradiction, in 1991, the authors proposed p-i-n organic solar cells in which the i-interlayer is a co-deposited film composed of p-and n-type organic semiconductors (Figure 4a) [5,6]. The original concept is that the positive and negative charges from ionized donors and acceptors in n-type and p-type organic semiconductors, respectively, are compensated by each other, and the resulting co-deposited interlayer behaves like an intrinsic semiconductor.…”

“…Conventional p-i-n cells (Section 2.2) [5,6] incorporating a quasi-vertical superlattice (Sections 3.1 and 3.2) [12] were used to evaluate the effects of high-purification.…”

“…In 1991, the author proposed p-i-n organic solar cells in which the i-interlayer is a co-deposited film of p-and n-type organic semiconductors [5,6]. This is the first organic solar cell having a molecular blend, i.e., the so-called bulk heterojunction [7].…”

Evaluation of Thin Film Surface Shape as a Function of Dispersant Concentration in Carbon Nanotube Thin Film Fabrication via the Electrospray Method

“…At present, indium tin oxide (ITO) is widely used for the main transparent electrode films in liquid crystal display panels and solar batteries made of organic electroluminescent materials, touch panels, flat panel displays, and so on [1][2][3][4][5][6]. However, indium, which is a rare metal, is expensive, and its supply is limited.…”