Fabrication and performance of a monolithic dye-sensitized TiO2/Cu(In,Ga)Se2 thin film tandem solar cell

Abstract

Tandem solar cells using different bandgap absorbers allow efficient photovoltaic conversion in a wide range of the solar spectrum. The optical gaps of the dye-sensitized solar cell and the Cu͑In, Ga͒Se 2 solar cell are ideal for application in double-junction devices and a mechanically stacked device has been reported recently. We report on the monolithic integration of these subcells to cut optical losses at needless interfaces and material costs, achieving 12.2% conversion efficiency at full sunlight. The high open-circuit voltage confirms the series connection, but corrosion of the Cu͑In, Ga͒Se 2 cell by the redox mediator ͑I − / I 3 − couple͒ of the dye-sensitized cell and an associated voltage loss ͑Ϸ140 mV͒ limits performance.

Photovoltaic Universal Joints: Ball‐and‐Socket Interfaces in Molecular Photovoltaic Cells

“…While OPVs are attractive as materials for conversion of sunlight into electrical energy, [1] higher conversion efficiencies [2] are needed for OPVs to become a viable technology. [3][4][5][6] Regardless of the type of OPV, either a bilayer [7] or bulk-heterojunction (BHJ) [4] (Figure 1 A), the interface between the hole and electron transporting films is the critical locus for exciton formation and dissociation. [8][9][10][11] In inorganic materials, the interface between two semiconductors is crucially important in determining and controlling the electrical properties of these materials and is controlled by a heteroepitaxial growth of one crystalline material on another.…”

Coupled Optical and Electronic Modeling of Dye-Sensitized Solar Cells for Steady-State Parameter Extraction

“…The accurate, layer-resolved quantification of these losses could become useful for the optimization of tandem solar cells, where a The Journal of Physical Chemistry C ARTICLE DSC is used as top cell, and the transmitted near-infrared light is absorbed by a bottom cell. 31 The absorptance in the photoactive layer 3 is separated into the absorptance by the dye, A dye (λ) = f abs (λ), and the absorptance by the remaining components, A 0 3 (mostly triiodide in the pores, but also some impurities in the TiO 2 , see Supporting Information. A dye and A 0 3 are labeled as 3 dye and 3 elec in the figures, respectively.…”

Tandem Dye-Sensitized Solar Cells Based on TCO-less Back Contact Bottom Electrodes

“…This offers the possibility of not only enhancing Jsc by wide wavelength photon harvesting but also enhancement in the Voc by connecting the top and bottom cells in series. In the case of series connected tandem solar cells non-complimentary light absorption by top and bottom cells, although leads to enhanced Voc but final out external PCE is either unchanged are slightly improved [26][27]. Taking these points in to consideration we have utilized sensitizing dyes D131, N719 and PC25 having complementary electron absorption spectra which has been shown in the figure 3 along with their molecular structure [15,25].…”