Role of solvent dielectric properties on charge transfer from PbS nanocrystals to molecules.
Transfer of photoexcited charge from PbS nanocrystals to ligand molecules is investigated in different solvents. We find that the charge transfer rate increases dramatically with solvent dielectric constant. This trend is accounted for by a modified Marcus theory that incorporates only static dielectric effects. The choice of solvent allows significant control of the charge transfer process. As an important example, we find that PbS nanocrystals dispersed in water exhibit charge transfer rates 1000 times higher than the same nanocrystals in organic solvent. Rapid charge extraction will be important to efficient nanocrystal-based photovoltaic and photodetector devices.
Hyun
Byung-Ryool
BR
School of Applied and Engineering Physics, Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14850, USA. bh73@cornell.edu
Bartnik
A C
AC
Lee
Jin-Kyun
JK
Imoto
Hiroaki
H
Sun
Liangfeng
L
Choi
Joshua J
JJ
Chujo
Yoshiki
Y
Hanrath
Tobias
T
Ober
Christopher K
CK
Wise
F W
FW
D003460:Crystallization; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007854:Lead / Q000737:chemistry*; D008024:Ligands; D008956:Models, Chemical; D015233:Models, Statistical; D008968:Molecular Conformation; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010777:Photochemistry / Q000379:methods; D012997:Solvents / Q000737:chemistry; D013440:Sulfides / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics
D008024:Ligands; D012997:Solvents; D013440:Sulfides; C018391:lead sulfide; D007854:Lead