High Efficiency Quantum Dot Sensitized Solar Cells Based on Direct Adsorption of Quantum Dots on Photoanodes

Abstract

Unambiguously direct adsorption (DA) of initial oil-soluble quantum dots (QDs) on TiO film electrode is a convenient and simple approach in the construction of quantum dot sensitized solar cells (QDSCs). Regrettably, low QD loading amount and poor reproducibility shadow the advantages of DA route and constrain its practical application. Herein, the influence of experimental variables in DA process on QD loading amount as well as on the photovoltaic performance of the resultant QDSCs was investigated and optimized systematically, including the choice of solvent, purification of QDs, and sensitization time, as well as QD concentration. Experimental results demonstrated that it is essential to choose appropriate solvent as well as control purification cycles of original QD suspensions so as to realize satisfactory QD loading amount and ensure the high reproducibility. In addition, DA mode renders efficient electron injection from QD to TiO, yet low QD loading amount and adverse QD agglomeration in comparison with the well-developed capping ligand induced self-assembly (CLIS) deposition approach. Mg treatment on TiO photoanodes can promote the QD loading amount in DA mode. The optimized QDSCs based on DA mode exhibited efficiencies of 6.90% and 9.02% for CdSe and Zn-Cu-In-Se QDSCs, respectively, which were comparable to the best results based on CLIS mode (6.88% and 9.56%, respectively).

Facile synthesis of CdS Quantum dots for QDSSC with high photo current density

“…TiO 2 photoanode was prepared by doctor blade method with active area of 0.25 cm 2 [23]. Green CdS was loaded on to TiO 2 photoanode by direct absorption method [24]. For comparative analysis, the CdS QDs were loaded on to TiO 2 photoanode using SILAR method too [25].…”

Effect of co-sensitization of InSb quantum dots on enhancing the photoconversion efficiency of CdS based quantum dot sensitized solar cells

“…Over which InSb QDs were made to load by direct absorption, followed by drying with N 2 gas pursing for 5 minutes. [43][44][45][46][47][48][49] 2.3.3 Counter electrode. Initially FTO glass slides were well cleaned and were immersed in isopropanol and sonicated for 30 min and washed with double distilled water and ethanol.…”

“…Electrodes were sandwiched together and the space between electrodes was lled with electrolyte. 49,50 I-V characteristics of the prepared QDSSC were studied by Solar Simulator (1 Sun Oriel Class AAA).…”

Exploring dynamics of resonance energy transfer in hybrid Quantum Dot Sensitized Solar Cells (QDSSC)

“…Quantum dot sensitized solar cells developed along with DSSC have also shown great promise in the recent years with their exciting physical and chemical properties due to quantum confinement effects [2]. The QD based solar cells are predicted to show good efficiencies due to their unique property of multiple exciton generation involving formation of more than one electron -hole pair upon absorption of a single photon.…”