Metal complex photosensitizer and photovoltaic cell

• US 6,245,988 B1
• Filed: 11/02/1999
• Issued: 06/12/2001
• Est. Priority Date: 05/07/1997
• Status: Expired due to Term

• Current Assignee: Ecole polytechnique fãdãrale de lausanne epfl (Schweizerische Eidgenossenschaft)
• Original Assignee: Ecole polytechnique fãdãrale de lausanne epfl (Schweizerische Eidgenossenschaft)
• Inventors: Péchy, Péter, Nazeeruddin, Mohammad Khaja, Grätzel, Michael
• Primary Examiner(s): DIAMOND, ALAN D
• Application Number:
  US09/423,162
• Time in Patent Office: 588 Days
• Field of Search: 136/252, 136/263, 257/40, 257/428, 257/431, 546/2, 546/10, 546/11, 546/12, 546/8, 546/9, 548/101, 548/107, 548/108, 548/109, 534/14, 429/111, 556/137, 556/138, 556/140, 556/145, 556/146
• US Class Current: 136/263
• CPC Class Codes: C07F 15/0026 without a metal-carbon linkage
• CPC Class Codes: C07F 15/0053 without a metal-carbon linkage
• CPC Class Codes: C07F 9/58 Pyridine rings
• CPC Class Codes: C09B 57/10 Metal complexes of organic compounds not being dyes in uncomplexed form
• CPC Class Codes: H01G 9/2031 comprising titanium oxide, e.g. TiO2 H01G9/2036 takes precedence
• CPC Class Codes: H01G 9/2059 comprising an organic dye as the active light absorbing material, e.g. adsorbed on an electrode or dissolved in solution
• CPC Class Codes: H10K 85/344 comprising ruthenium
• CPC Class Codes: Y02E 10/542 Dye sensitized solar cells
• CPC Class Codes: Y02E 10/549 Organic PV cells

Abstract

A photosensitizer complex of formulae (Ia) MX₃L_t or (Ib) MXYL_t in which M is a transition metal selected from ruthenium, osmium, iron, rhenium and technetium, preferably ruthenium or osmium; each X is a co-ligand independently selected from NCS—, Cl—, Br—, I—, CN—, NCO—, H₂O, NCN²⁻; pyridine unsubstituted or substituted by at least one group selected from vinyl, primary, secondary or tertiary amine, OH and C_1-30 alkyl, preferably NCS—; and L_t is a tridentate ligand comprising heterocycles such as pyridine, thiophene, imidazole, pyrazole, triazole, carrying at least one carboxylic, phosphoric, hydoxamic acid or a chelating group. A photovoltaic cell comprising an electrically conductive layer deposited on a support to which at least one titanium dioxide layer has been applied and, as a photosensitizer applied to the titanium dioxide layer, a photosensitizer complex of formula (Ia) or Ib) as specified above.

Claims

1. A photosensitizer complex of formula (Ia)

2. A photosensitizer complex of formula (Ia), according to claim 1, characterized in that

M is ruthenium or osmium;

each X is independently selected from NCS⁻

and CN⁻

; and

L_t has the formula (IIa);

wherein

R₁ is a phenyl substituted by at least one of the groups selected from COOH, PO(OH)₂, PO(OR₃)(OH) and CO(NHOH);

R₃ being selected from C_1-30 alkyl and phenyl; and

A and B are both 2-pyridyl.

3. A photosensitizer complex of formula (Ia), according to claim 1, characterized in that

M is ruthenium or osmium;

each X is independently selected from NCS⁻

and CN⁻

; and

L_t has the formula (IIa);

wherein

R₁ is a COOH; and

A and B are both 4-carboxy-2-pyridyl.

9. A photosensitizer complex of formula (Ia), according to claim 1, characterized in that

M is osmium;

each X is independently selected from NCS⁻

and CN⁻

; and

L_t has the formula (IIa);

wherein

R₁ is a phenyl substituted by at least one of the groups selected from COOH, PO(OH)₂, PO(OR₃)(OH) and CO(NHOH);

R₃ being selected from C_1-30 alkyl and phenyl; and

A and B are both 2-pyridyl.

11. A photovoltaic cell comprising an electrically conductive layer deposited on a support to which at least one titanium dioxide layer has been applied, characterised in that it comprises, as a photosensitizer applied to the titanium dioxide layer, a photosensitizer complex of formula (Ia) as specified in claim 1.

4. A photosensitizer complex of formula (Ib)

5. A photosensitizer complex of formula (Ib), according to claim 4, characterized in that

each X is independently selected from NCS⁻

and CN⁻

; and

L_t has the formula (IIa);

wherein

R₁ is a COOH; and

A and B are both 4-carboxy-2-pyridyl.

12. A photovoltaic cell comprising an electrically conductive layer deposited on a support to which at least one titanium dioxide layer has been applied, characterised in that it comprises, as a photosensitizer applied to the titanium dioxide layer, a photosensitizer complex of formula (Ib) as specified in claim 4.

6. A photosensitizer complex of formula (Ib)

7. A photosensitizer complex of formula (Ib), according to claim 6, characterized in that

each X is independently selected from NCS⁻

and CN⁻

; and

L_t has the formula (IIa);

wherein

R₁ is a phenyl substituted by at least one of the groups selected from COOH and CO(NHOH); and

A and B are both 2-pyridyl.

13. A photovoltaic cell comprising an electrically conductive layer deposited on a support to which at least one titanium dioxide layer has been applied, characterised in that it comprises, as a photosensitizer applied to the titanium dioxide layer, a photosensitizer complex of formula (Ib) as specified in claim 6.

8. A photosensitizer complex of formula (Ib)

10. A photosensitizer complex of formula (Ib), according to claim 8, characterized in that

M is osmium;

each X is independently selected from NCS⁻

and CN⁻

; and

L_t has the formula (IIa);

wherein

R₁ is COOH; and

A and B are both 4-carboxy-2-pyridyl.

14. A photovoltaic cell comprising an electrically conductive layer deposited on a support to which at least one titanium dioxide layer has been applied, characterised in that it comprises, as a photosensitizer applied to the titanium dioxide layer, a photosensitizer complex of formula (Ib) as specified in claim 8.