Enhanced Sunlight Harvesting of Dye-Sensitized Solar Cells Assisted with Long Persistent Phosphor Materials

Abstract

TiO 2 nanoparticle-based dye-sensitized solar cells (DSSCs) were modified by depositing a layer of a long-persistent phosphor, SrAl 2 O 4 :Eu 2+ ,Dy 3+ , on top of the TiO 2 nanoparticle layer to prepare working electrodes of the DSSCs. SrAl 2 O 4 :Eu 2+ ,Dy 3+ red-shifted the short UV wavelengths into the main absorption range of the dye commonly used in DSSCs. The SrAl 2 O 4 :Eu 2+ ,Dy 3+ layer also acted as a light-scattering layer to reduce the loss of visible light. Incident photon to current conversion efficiency measurements showed that the application of such phosphor materials enhanced light-harvesting. The open-circuit voltage was found to be higher in the modified DSSCs. The electrons produced by the SrAl 2 O 4 :Eu 2+ ,Dy 3+ particles contribute to the reduction of I 3 − to I − , leading to a lower I 3 − concentration in the electrolyte. This reduces the recapture of electrons injected in the conduction band of TiO 2 by triiodide ions and promotes the open circuit voltage. The performance of the modified DSSC device was improved compared with the cell using a working electrode without this phosphor layer. An overall 13% improvement in conversion efficiency of modified DSSCs was achieved due to the presence of the phosphor layer.

Effect of the Li+ ion on the multimodal emission of a lanthanide doped phosphor

“…[1][2][3][4][5][6] Recent research on these phosphors broadly covers two principle areas, namely bio-imaging and energy harvesting. [14][15][16][17] The conversion efficiency of silicon solar cells for UV (250-400 nm) and IR sub-band gap i.e. [7][8][9][10][11][12][13] On the other hand, the second appealing application, i.e.…”

Recent Progress and Emerging Applications of Rare Earth Doped Phosphor Materials for Dye‐Sensitized and Perovskite Solar Cells: A Review

“…These materials have good optical match with commonly used dye in DSCs and as a light‐scattering layer improves the light harvesting capability resulting in improved Jsc depicted in Figure (b and c). SrAl 2 O 4 : Eu 2+ , Dy 3+ phosphor reduces I 3 − concentration in the electrolyte which increases the open‐circuit voltage …”

Increased efficiency of dye-sensitized solar cells by addition of rare earth oxide microparticles into a titania acceptor

“…For example, Y and Nd have been shown to both enhance [35,37] and decrease [19,36] the efficiency in different reports. Another type of material involves upconverting [38][39][40][41][42][43][44], downconverting [25,40,[45][46][47][48][49][50], or dual-mode [51] luminescent rare earth nanostructures, which allow improved light collection efficiency when incorporated into the TiO 2 photoanode in DSSCs. They can also help improve efficiency through light scattering [39,43,50,52], altering the energy level of the TiO 2 [43,48,53], or by reducing recombination processes [47,54,55] at the TiO 2 /electrolyte interface.…”