Photoisomerization of Covalently Attached Diarylethene on Locally Functionalized Single-Walled Carbon Nanotubes for Photoinduced Wavelength Switching of Near-Infrared Photoluminescence

Abstract

Near-infrared photoluminescence (NIR PL) at regions over 1000 nm is used by advanced optical technologies such as quantum communication and deep tissue bioimaging. We demonstrate that covalent attachment of a diarylethene derivative to single-walled carbon nanotubes (SWCNTs) introduces sp 3 carbon defects into the crystalline sp 2 carbon networks of SWCNTs through chemical functionalization by which red-shifted and bright NIR PL band at 1142 nm appears. Moreover, its PL wavelength switching is achieved reversibly and repeatedly based on photoisomerization of the diarylethene moieties on the nanotubes. The photoswitching phenomena confirmed by spectroscopic measurements and theoretical calculations reveal that the band gaps for PL change according to the diarylethene isomerization on the nanotubes.

Aza-bicyclooctadiene/tetracyclooctane couples as promising photoswitches for molecular solar thermal energy storage applications

“…, molecular photoswitches, have attracted widespread attention among the scientific research community. 1–12 An ideal photoswitching molecule forms a metastable isomer upon irradiation and converts back to the stable parent compound either thermally, electrochemically or with an aid of a catalyst. 13–16 The two photo-isomers of the molecular photochromic couple have different physical and chemical properties.…”

“…Light responsive molecules that undergo reversible photoinduced excitation to give high energy metastable isomers, i.e., molecular photoswitches, have attracted widespread attention among the scientific research community. [1][2][3][4][5][6][7][8][9][10][11][12] An ideal photoswitching molecule forms a metastable isomer upon irradiation and converts back to the stable parent compound either thermally, electrochemically Laboratory of Advanced Computation and Theory for Materials and Chemistry, Department of Chemistry, National Institute of Technology Warangal (NITW), Warangal, Telangana-506004, India. E-mail: ravinder_pawar@nitw.ac.in † Electronic supplementary information (ESI) available: Thermochemical and photophysical properties and UV-vis spectra of substituted 1-aza-BOD/TCO and 1,4-biaza-BOD/TCO systems, and UV-vis spectra of 2-aza-BOD and TCO.…”

Azide modification forming luminescent sp2 defects on single-walled carbon nanotubes for near-infrared defect photoluminescence

“…Sp 3 -carbon defects have been generally produced using diazonium chemistry, reductive alkylation, and so on. These organic chemistry approaches have enabled the attachment of functional molecules on defect sites for dynamic E Ã 11 PL wavelength variations based on photochromic reactions 8 and molecular recognition, 9,10 as well as for broad E Ã 11 PL wavelength modulation. [11][12][13] Properties of the localized excitons in lf-SWCNTs could be significantly changed depending on the structures of the defect sites.…”

“…For unmodified SWCNTs, a peak appeared at 980 nm, which was assigned to the PL signal based on the lowest energy transition (E 11 ) of (6,5) SWCNTs. A small peak at 1115 nm was assigned to the E 11 PL of (8,4) SWCNTs that slightly contaminated the used (6,5)-rich SWCNT sample. For lf-SWCNTs-N, additional PL was observed at 1116 nm.…”

Azide modification of single-walled carbon nanotubes for near-infrared defect photoluminescence by luminescent sp2 defect formation

“…For pristine SWCNTs, a peak appeared at 980 nm, which was assigned to the PL signal based on the lowest energy transition (E11) of (6,5) SWCNTs. A small peak at 1115 nm was assigned to the E11 PL of (8,4) SWCNTs that slightly contaminated the used (6,5)-rich SWCNT sample. For lf-SWCNTs-N, additional PL was observed at 1116 nm.…”