Photovoltaic Cell

• US 20090165857A1
• Filed: 12/24/2008
• Published: 07/02/2009
• Est. Priority Date: 12/27/2007
• Status: Abandoned Application

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: NAITO, Hiroto, YOSHIMOTO, Naoki
• Application Number:
  US12/343,659
• Publication Number:
  US 20090165857A1
• Time in Patent Office: Days
• US Class Current: 136/261
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H10K 2102/103 comprising indium oxides, e.g. ITO
• CPC Class Codes: H10K 30/211 comprising multiple junctions, e.g. double heterojunctions
• CPC Class Codes: H10K 30/30 comprising bulk heterojunctions, e.g. interpenetrating networks of donor and acceptor material domains
• CPC Class Codes: H10K 30/50 Photovoltaic [PV] devices
• CPC Class Codes: H10K 85/113 Heteroaromatic compounds comprising sulfur or selene, e.g. polythiophene
• CPC Class Codes: H10K 85/1135 Polyethylene dioxythiophene [PEDOT]; Derivatives thereof
• CPC Class Codes: H10K 85/211 Fullerenes, e.g. C60
• CPC Class Codes: Y02E 10/549 Organic PV cells

Abstract

An organic thin-film photovoltaic cell comprises: a transparent conductor layer; a hole transport layer formed on the transparent conductor layer; a photoelectric conversion layer formed on the hole transport layer; an electron transport layer formed on the photoelectric conversion layer; and a counter electrode formed on the electron transport layer, in which: the photoelectric conversion layer is made of a mixture of a p-type semiconductor molecule or p-type polymer and an n-type semiconductor molecule; the electron transport layer contains the n-type semiconductor molecule; and the p-type semiconductor molecule or p-type polymer contained in the photoelectric conversion layer and exposed at an interface between the photoelectric conversion layer and the electron transport layer is in contact with the n-type semiconductor molecule contained in the electron transport layer.

Claims

1. An organic thin-film photovoltaic cell, comprising:

a transparent conductor layer;

a hole transport layer formed on the transparent conductor layer;

a photoelectric conversion layer formed on the hole transport layer;

an electron transport layer formed on the photoelectric conversion layer; and

a counter electrode formed on the electron transport layer, wherein;

the photoelectric conversion layer is made of a mixture of a p-type semiconductor molecule or p-type polymer and an n-type semiconductor molecule;

the electron transport layer contains the n-type semiconductor molecule; and

the p-type semiconductor molecule or p-type polymer contained in the photoelectric conversion layer and exposed at an interface between the photoelectric conversion layer and the electron transport layer is in contact with the n-type semiconductor molecule contained in the electron transport layer.

2. The organic thin-film photovoltaic cell according to claim 1, wherein:

the electron transport layer has functions of blocking hole injection from a p-type semiconductor composed of the p-type semiconductor molecule into the counter electrode and preventing recombination at the counter electrode.

3. The organic thin-film photovoltaic cell according to claim 1, wherein:

the valence band level of the electron transport layer is 0.5 eV or more deeper than that of the p-type semiconductor polymer or p-type semiconductor molecule contained in the photoelectric conversion layer, with reference to the vacuum energy level.

4. The organic thin-film photovoltaic cell according to claim 1, wherein:

the conduction band level of the electron transport layer is less than 0.3 eV deeper than that of the n-type semiconductor molecule contained in the photoelectric conversion layer, with reference to the vacuum energy level.

5. The organic thin-film photovoltaic cell according to claim 3, wherein:

the conduction band level of the electron transport layer is less than 0.3 eV deeper than that of the n-type semiconductor molecule contained in the photoelectric conversion layer, with reference to the vacuum energy level.

6. The organic thin-film photovoltaic cell according to claim 1, wherein:

the thickness of the electron transport layer is 0.1 nm or more and 50 nm or less.