Subnanometer Ga2O3 tunnelling layer by atomic layer deposition to achieve 1.1 V open-circuit potential in dye-sensitized solar cells.
Herein, we present the first use of a gallium oxide tunnelling layer to significantly reduce electron recombination in dye-sensitized solar cells (DSC). The subnanometer coating is achieved using atomic layer deposition (ALD) and leading to a new DSC record open-circuit potential of 1.1 V with state-of-the-art organic D-π-A sensitizer and cobalt redox mediator. After ALD of only a few angstroms of Ga(2)O(3), the electron back reaction is reduced by more than an order of magnitude, while charge collection efficiency and fill factor are increased by 30% and 15%, respectively. The photogenerated exciton separation processes of electron injection into the TiO(2) conduction band and the hole injection into the electrolyte are characterized in detail.
Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, Swiss Federal Institute of Technology (EPFL) , Station 6, 1015 Lausanne, Switzerland. aravindkumar.chandiran@epfl.ch
Aravind Kumar
AK
Chandiran
Nicolas
N
Tetreault
Robin
R
Humphry-Baker
Florian
F
Kessler
Etienne
E
Baranoff
Chenyi
C
Yi
Mohammad Khaja
MK
Nazeeruddin
Michael
M
Grätzel