Chapter 2
A Path to the Blended Junction
Masahiro Hiramoto
2.1 Shock of Two-Layer Solar Cell
The author had been interested in the energy problem from the time of his undergraduate studies and was involved in the research on the photoelectrochemical conversion of solar light [1–5] and photocatalysis [6] during the early stage of his career
from 1980 to 1988, focusing on inorganic semiconductors such as silicon [2–5] and
cadmium sulfide [6]. The photoelectrochemical cells using such inorganic semiconductors typically showed the photocurrent density of approximately 20 mAcm
−2
under the irradiation of simulated solar light [1–5]. At that time, the author had the
impression that compared to the high performance of inorganic solar cells, the performance characteristics of organic solar cells were poor. Organic solar cells of those
days with the Schottky junction with corrosive metals such as Al showed extremely
small photocurrents of the order of nano- and microamperes as summarized in review
papers [7, 8].
In 1986, Ching W. Tang of Eastman Kodak Co. published a report in Applied
Physics Letters titled “Two-layer organic solar cell” [9]. Surprisingly, he also reported
his famous work on organic electroluminescence almost simultaneously in 1987 [10].
Following this report, in 1988 the author shifted his research field from inorganic
semiconductors to organic semiconductors. At the time, the author was quite shocked
when he first encountered the two-layer paper and was particularly surprised by the
current–voltage characteristics shown in Fig. 2.1 of [9]. Tang reported that the shortThe original version of this chapter was revised: Figure 2.1 have been updated with new Figure.
The correction to this chapter is available at https://doi.org/10.1007/978-981-15-9113-6_11
M. Hiramoto (B)
National Institutes of Natural Sciences, Institute for Molecular Science, 5-1 Higashiyama
Myodaiji, Aichi, Okazaki 444-8787, Japan
e-mail: hiramoto@ims.ac.jp
© Springer Nature Singapore Pte Ltd. 2021, corrected publication 2021
M. Hiramoto and S. Izawa (eds.), Organic Solar Cells,
https://doi.org/10.1007/978-981-15-9113-6_2
23
A Path to the Blended Junction
Masahiro Hiramoto
2.1 Shock of Two-Layer Solar Cell
The author had been interested in the energy problem from the time of his undergraduate studies and was involved in the research on the photoelectrochemical conversion of solar light [1–5] and photocatalysis [6] during the early stage of his career
from 1980 to 1988, focusing on inorganic semiconductors such as silicon [2–5] and
cadmium sulfide [6]. The photoelectrochemical cells using such inorganic semiconductors typically showed the photocurrent density of approximately 20 mAcm
−2
under the irradiation of simulated solar light [1–5]. At that time, the author had the
impression that compared to the high performance of inorganic solar cells, the performance characteristics of organic solar cells were poor. Organic solar cells of those
days with the Schottky junction with corrosive metals such as Al showed extremely
small photocurrents of the order of nano- and microamperes as summarized in review
papers [7, 8].
In 1986, Ching W. Tang of Eastman Kodak Co. published a report in Applied
Physics Letters titled “Two-layer organic solar cell” [9]. Surprisingly, he also reported
his famous work on organic electroluminescence almost simultaneously in 1987 [10].
Following this report, in 1988 the author shifted his research field from inorganic
semiconductors to organic semiconductors. At the time, the author was quite shocked
when he first encountered the two-layer paper and was particularly surprised by the
current–voltage characteristics shown in Fig. 2.1 of [9]. Tang reported that the shortThe original version of this chapter was revised: Figure 2.1 have been updated with new Figure.
The correction to this chapter is available at https://doi.org/10.1007/978-981-15-9113-6_11
M. Hiramoto (B)
National Institutes of Natural Sciences, Institute for Molecular Science, 5-1 Higashiyama
Myodaiji, Aichi, Okazaki 444-8787, Japan
e-mail: hiramoto@ims.ac.jp
© Springer Nature Singapore Pte Ltd. 2021, corrected publication 2021
M. Hiramoto and S. Izawa (eds.), Organic Solar Cells,
https://doi.org/10.1007/978-981-15-9113-6_2
23