Hybrid photoactive assemblies: electron injection from host-guest complexes into semiconductor nanoparticles.
Novel ternary assemblies consisting of fully encapsulated host-guest complexes (hemicarceplexes) and wide band gap semiconductor nanoparticles were investigated. The water-soluble amphiphilic host (octacarboxyhemicarcerand) traps the hydrophobic chromophore within its cavity and binds to the surface of metal oxide nanoparticles. Fluorescence quenching and fast charge injection, kforward >/= 7 x 109 s-1, from the S2 state of encapsulated azulene were observed. Charge recombination proceeds at a much lower rate of 2 x 107 s-1. Interestingly, the recombination kinetics is homogeneous, suggesting that electron tunneling through the wall of the "molecular container" is the rate-limiting step of the process.
Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, USA.
Cynthia
C
Pagba
Giovanni
G
Zordan
Elena
E
Galoppini
Eugene L
EL
Piatnitski
Sarmimala
S
Hore
Kurt
K
Deshayes
Piotr
P
Piotrowiak