We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Investigation of Interfacial Charge Separation at PbS QDs/(001) TiO<sub>2</sub> Nanosheets Heterojunction Solar Cell.
- Authors
Ghadiri, Elham; Liu, Bin; Moser, Jacques‐E.; Grätzel, Michael; Etgar, Lioz
- Abstract
In the recent years, the heterojunction solar cells based on quantum dots (QDs) have attracted attention due to strong light absorbing characteristics and the size effect on the bandgap tuning. This paper reports on the kinetics of interfacial charge separation of PbS QDs/(001) TiO2 nanosheets heterojunction solar cells. PbS QDs are deposited using a bifunctional linker molecule on two different TiO2 films, i.e., TiO2 nanosheets (with 001 dominant exposed facet) and TiO2 nanoparticles (with 101 dominant exposed facet). Upon bandgap excitation, electrons are transferred from the PbS QDs conduction band to the lower lying conduction band of TiO2. Based on the ultrafast pump-probe laser spectroscopy technique, the kinetics of charge separation is scrutinized at the PbS/TiO2 interface. The interfacial charge separation at PbS/TiO2 nanosheets films made of (001) dominant exposed facets is five times faster than that on (101) dominant exposed facets TiO2 nanoparticles. The quantum yields for charge injection are higher for the (001) TiO2 nanosheets than the (101) TiO2 nanoparticles due to enhanced interfacial interaction with (001) surface compared to the (101) nanoparticles. The superior interfacial charge separation at PbS/(001) nanosheets respect to PbS/(101) nanoparticles is consistent with the higher photocurrent and enhanced power conversion efficiency in the PbS QDs/(001) TiO2 heterojunction solar cell. The use of (001) TiO2 nanosheets can be a better alternative to conventional mesoporous TiO2 films in QD heterojunction solar cells and perovskites-based heterojunction solar cells.
- Subjects
QUANTUM dots; LEAD sulfide; SEPARATION (Technology); TITANIUM oxides; HETEROJUNCTIONS; SOLAR cells; BAND gaps; PUMP probe spectroscopy
- Publication
Particle & Particle Systems Characterization, 2015, Vol 32, Issue 4, p483
- ISSN
0934-0866
- Publication type
Article
- DOI
10.1002/ppsc.201400210