Amphiphilic Zinc Porphyrin Single‐Walled Carbon Nanotube Hybrids: Efficient Formation and Excited State Charge Transfer Studies. Issue 48 (18th January 2021)

• Record Type: Journal Article
• Authors: Menon, Arjun; Münich, Peter W.; Wagner, Pawel; Officer, David L.; Guldi, Dirk M.
• Is Part Of: Small. Volume 17:Issue 48(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-01-18
• Subjects: carbon nanotubes -- charge‐transfer interactions -- doping -- non‐covalent functionalization -- porphyrins; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202005648
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Herein, the microscopic and spectroscopic characterization of a novel non‐covalent electron donor−acceptor system, in which three different metalloporphyrins (1, 2, and 3 ) play the dual role of light harvester and electron donor with SWCNTs as electron acceptor, is described. To this end, microscopy, that is, atomic force microscopy (AFM) and transmission electron microscopy (TEM) corroborate the formation of 1 ‐SWCNT, 2 ‐SWCNT, and 3 ‐SWCNT. Spectroscopy by means of Raman, fluorescence, and transient absorption spectroscopy confirmed efficient charge‐transfer interaction from photoexcited metalloporphyrins to SWCNTs in the ground and excited state of 1 ‐SWCNT, 2 ‐SWCNT, and 3 ‐SWCNT. The complementary use of spectroelectrochemical and transient absorption measurements substantiates the formation of one‐electron oxidized metalloporphyrins after photoexcitation. Multiwavelength global analysis provides insights into the charge‐separation and recombination processes in 1 ‐SWCNT, 2 ‐SWCNT, and 3 ‐SWCNT upon photoexcitation. Notably, both the charge‐separation and recombination dynamics are fastest in 2 ‐SWCNT. Importantly, the strongest interactions in the steady‐state experiments are associated with the fastest excited state decay in the time‐resolved measurements. Abstract : A novel electron donor−acceptor system with zinc porphyrins (ZnPs) as a promoter for the self‐assembly onto single walled carbon nanotubes (SWCNTs) is presented. The ultrafast electronic processes, is a charge transfer between ZnPs and SWCNTs are on the time scale of picoseconds. They start with the formation of simultaneously populated excited states, whose decay proceeds via a transient charge‐separated state.