2 A Path to the Blended Junction
43
to dominate the magnitude of V oc . These advances are described in detail in Chap. 8.
Moreover, the carrier generation process via the CT states investigated by transient
absorption spectroscopy is discussed in Chap. 6.
2.4 Conclusion
This chapter provides a detailed overview of the invention of the blended junction.
By recording the photovoltaic behaviors as a function of the fabrication of the
interface, the molecular contact between the PTC and Pc molecules was revealed
to be a key for the excellent photocarrier generation ability. This insight guided
the author to develop the blended junctions (p-i-n junctions) with a vast number of
PTC:Pc molecular contacts that doubled the photocarrier generation efficiency by
overcoming the technical difficulties of co-deposition [11].
The three-layer organic solar cell was the first report of the blended junction
[11, 21]. In those initial papers, the following predictions regarding the future
organic solar cells already appeared: (1) p-i-n energetic structure and cells fabricated
by doping, (2) percolation as an inevitable issue for the blended junction, (3)
efficient carrier photogeneration via an exciplex (PTC
− –PC
+ )* and donor–acceptor
sensitization that are related to the charge–transfer (CT) state.
Blended junctions have become indispensable for today’s organic solar cells.
References
1. Matsumura, M., Hiramoto, M., Tsubomura, H.: Photoelectrolysis of water under visible light
with doped SrTiO 3 electrodes. J. Electrochem. Soc. 130, 326–330 (1983)
2. Nakato, Y., Yoshimura, M., Hiramoto, M., Tsumura, A., Murahashi, T., Tsubomura, H.: pn junction silicon electrode coated with noble metal for efficient solar photoelectrolysis of
hydrogen iodide. Bull. Chem. Soc. Jpn 57, 355–360 (1984)
3. Nakato, Y., Hiramoto, M., Iwakabe, Y., Tsubomura, H.: ESCA and photoelectrochemical
studies of p-n junction silicon electrodes protected by platinum deposition for use in solar
energy conversion. J. Electrochem. Soc. 132, 330–334 (1985)
4. Tsubomura, H., Nakato, Y., Hiramoto, M., Yano, H.: Metal oxide coated p-n junction silicon
electrodes for photoelectrochemical solar energy conversion. Can. J. Chem. 63, 1759–1762
(1985)
5. Hiramoto, M., Hashimoto, K., Sakata, T.: Visible-light induced water splitting on new
semiconductor electrodes made by photolithography. Chem. Lett. 1986, 899–902 (1986)
6. Matsumura, M., Hiramoto, M., Iehara, T., Tsubomura, H.: Photocatalytic and photoelectrochemical reactions of aqueous solutions of formic acid, formaldehyde, and methanol on
platinized CdS powder and at a CdS electrode. J. Phys. Chem. 88, 248–250 (1984)
7. Chamberlain, G.A.: Organic solar cells: A review 8, 47–83 (1983). and references therein
8. Wohrle, D., Meissner, D.: Organic solar cells. Adv. Mater. 3, 129–138 (1991). and references
therein
9. Tang, C.W.: Two-layer organic photovoltaic cell. Appl. Phys. Lett. 48, 183–185 (1986)
10. Tang, C.W., VanSlyke, S.A.: Organic electroluminescent diodes. Appl. Phys. Lett. 51, 913–915
(1987)
43
to dominate the magnitude of V oc . These advances are described in detail in Chap. 8.
Moreover, the carrier generation process via the CT states investigated by transient
absorption spectroscopy is discussed in Chap. 6.
2.4 Conclusion
This chapter provides a detailed overview of the invention of the blended junction.
By recording the photovoltaic behaviors as a function of the fabrication of the
interface, the molecular contact between the PTC and Pc molecules was revealed
to be a key for the excellent photocarrier generation ability. This insight guided
the author to develop the blended junctions (p-i-n junctions) with a vast number of
PTC:Pc molecular contacts that doubled the photocarrier generation efficiency by
overcoming the technical difficulties of co-deposition [11].
The three-layer organic solar cell was the first report of the blended junction
[11, 21]. In those initial papers, the following predictions regarding the future
organic solar cells already appeared: (1) p-i-n energetic structure and cells fabricated
by doping, (2) percolation as an inevitable issue for the blended junction, (3)
efficient carrier photogeneration via an exciplex (PTC
− –PC
+ )* and donor–acceptor
sensitization that are related to the charge–transfer (CT) state.
Blended junctions have become indispensable for today’s organic solar cells.
References
1. Matsumura, M., Hiramoto, M., Tsubomura, H.: Photoelectrolysis of water under visible light
with doped SrTiO 3 electrodes. J. Electrochem. Soc. 130, 326–330 (1983)
2. Nakato, Y., Yoshimura, M., Hiramoto, M., Tsumura, A., Murahashi, T., Tsubomura, H.: pn junction silicon electrode coated with noble metal for efficient solar photoelectrolysis of
hydrogen iodide. Bull. Chem. Soc. Jpn 57, 355–360 (1984)
3. Nakato, Y., Hiramoto, M., Iwakabe, Y., Tsubomura, H.: ESCA and photoelectrochemical
studies of p-n junction silicon electrodes protected by platinum deposition for use in solar
energy conversion. J. Electrochem. Soc. 132, 330–334 (1985)
4. Tsubomura, H., Nakato, Y., Hiramoto, M., Yano, H.: Metal oxide coated p-n junction silicon
electrodes for photoelectrochemical solar energy conversion. Can. J. Chem. 63, 1759–1762
(1985)
5. Hiramoto, M., Hashimoto, K., Sakata, T.: Visible-light induced water splitting on new
semiconductor electrodes made by photolithography. Chem. Lett. 1986, 899–902 (1986)
6. Matsumura, M., Hiramoto, M., Iehara, T., Tsubomura, H.: Photocatalytic and photoelectrochemical reactions of aqueous solutions of formic acid, formaldehyde, and methanol on
platinized CdS powder and at a CdS electrode. J. Phys. Chem. 88, 248–250 (1984)
7. Chamberlain, G.A.: Organic solar cells: A review 8, 47–83 (1983). and references therein
8. Wohrle, D., Meissner, D.: Organic solar cells. Adv. Mater. 3, 129–138 (1991). and references
therein
9. Tang, C.W.: Two-layer organic photovoltaic cell. Appl. Phys. Lett. 48, 183–185 (1986)
10. Tang, C.W., VanSlyke, S.A.: Organic electroluminescent diodes. Appl. Phys. Lett. 51, 913–915
(1987)