Improving photocurrent generation: supramolecularly and covalently functionalized single-wall carbon nanotubes-polymer/porphyrin donor-acceptor nanohybrids.
Novel nanohybrids based on covalently and noncovalently functionalized single-wall carbon nanotubes (SWNTs) have been prepared and assembled for the construction of photoactive electrodes. Polymer-grafted SWNTs were synthesized by free-radical polymerization of (vinylbenzyl)trimethylammonium chloride. Poly[(vinylbenzyl)trimethylammonium chloride] (PVBTAn+) was also noncovalently wrapped around SWNTs to form stable, positively charged SWNT/PVBTAn+ suspensions in water. Versatile donor-acceptor nanohybrids were prepared by using the electrostatic/van der Waals interactions between covalent SWNT-PVBTAn+ and/or noncovalent SWNT/PVBTAn+ and porphyrins (H2P8- and/or ZnP8-). Several spectroscopic, microscopic, transient, and photoelectrochemical measurements were taken to characterize the resulting supramolecular complexes. Photoexcitation of the nanohybrids afforded long-lived radical ion pairs with lifetimes as long as 2.2 micros. In the final part, photoactive electrodes were constructed by using a layer-by-layer technique on an indium tin oxide covered glass support. Photocurrent measurements gave remarkable internal photon-to-current efficiencies of 3.81 and 9.90 % for the covalent ZnP8-/SWNT-PVBTAn+ and noncovalent ZnP8-/SWNT/PVBTAn+ complex, respectively, when a potential of 0.5 V was applied.
Rahman
G M Aminur
GMA
Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany), Fax: (+49) 913-1852-8307.
Troeger
Anna
A
Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany), Fax: (+49) 913-1852-8307.
Sgobba
Vito
V
Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany), Fax: (+49) 913-1852-8307.
Guldi
Dirk M
DM
Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany), Fax: (+49) 913-1852-8307.
Jux
Norbert
N
Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nuremberg, Henkestr. 42, 91054 Erlangen (Germany).
Balbino
Domenico
D
Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nuremberg, Henkestr. 42, 91054 Erlangen (Germany).
Tchoul
Maxim N
MN
Department of Chemistry, Oklahoma State University, Stillwater, OK 74078 (USA).
Ford
Warren T
WT
Department of Chemistry, Oklahoma State University, Stillwater, OK 74078 (USA).
Mateo-Alonso
Aurelio
A
Center of Excellence for Nanostructured Materials, CENMAT, Dipartimento di Scienze Farmaceutiche and INSTM, University of Trieste, Piazzale Europa 1, 34127 Trieste (Italy), Fax: (+39) 040-52572.
Prato
Maurizio
M
Center of Excellence for Nanostructured Materials, CENMAT, Dipartimento di Scienze Farmaceutiche and INSTM, University of Trieste, Piazzale Europa 1, 34127 Trieste (Italy), Fax: (+39) 040-52572.