title: Improving photocurrent generation: supramolecularly and covalently functionalized single-wall carbon nanotubes-polymer/porphyrin donor-acceptor nanohybrids.
abstract: 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.
authors.affiliation: Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany), Fax: (+49) 913-1852-8307.
authors.forename: G M Aminur
authors.initials: GMA
authors.lastname: Rahman
authors.affiliation: Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany), Fax: (+49) 913-1852-8307.
authors.forename: Anna
authors.initials: A
authors.lastname: Troeger
authors.affiliation: Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany), Fax: (+49) 913-1852-8307.
authors.forename: Vito
authors.initials: V
authors.lastname: Sgobba
authors.affiliation: Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany), Fax: (+49) 913-1852-8307.
authors.forename: Dirk M
authors.initials: DM
authors.lastname: Guldi
authors.affiliation: Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nuremberg, Henkestr. 42, 91054 Erlangen (Germany).
authors.forename: Norbert
authors.initials: N
authors.lastname: Jux
authors.affiliation: Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials, University of Erlangen-Nuremberg, Henkestr. 42, 91054 Erlangen (Germany).
authors.forename: Domenico
authors.initials: D
authors.lastname: Balbino
authors.affiliation: Department of Chemistry, Oklahoma State University, Stillwater, OK 74078 (USA).
authors.forename: Maxim N
authors.initials: MN
authors.lastname: Tchoul
authors.affiliation: Department of Chemistry, Oklahoma State University, Stillwater, OK 74078 (USA).
authors.forename: Warren T
authors.initials: WT
authors.lastname: Ford
authors.affiliation: 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.
authors.forename: Aurelio
authors.initials: A
authors.lastname: Mateo-Alonso
authors.affiliation: 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.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Prato