Near-infrared fluorescence of silicon phthalocyanine carboxylate esters
Abstract
Seven silicon(IV) phthalocyanine carboxylate esters (SiPcs, 1–7 ) with non-, partially- and per-fluorinated aliphatic (linear or branched at the alpha-carbon) and aromatic ester groups have been synthesized, their solid-state structures determined and their optoelectronic properties characterized. The SiPcs exhibit quasi-reversible oxidation waves (vs. Fc+/Fc) at 0.58–0.75 V and reduction waves at −0.97 to −1.16 V centered on the phthalocyanine ring with a narrow redox gap range of 1.70–1.75 V. Strong absorbance in the near-infrared (NIR) region is observed for 1–7 with the lowest-energy absorption maximum (Q band) varying little as a function of ester between 682 and 691 nm. SiPcs 1–7 fluorescence in the near-infrared with emission maxima at 691–700 nm. The photoluminescence quantum yields range from 40 to 52%. As a function of esterification, the SiPcs 1–7 exhibit moderate-to-good solubility in chlorinated solvents, such as 1,2-dichlorobenzene and chloroform.
Citation
Pal , A K , Varghese , S , Cordes , D B , Slawin , A M Z , Samuel , I D W & Zysman-Colman , E 2017 , ' Near-infrared fluorescence of silicon phthalocyanine carboxylate esters ' , Scientific Reports , vol. 7 , 12282 . https://doi.org/10.1038/s41598-017-12374-8
Publication
Scientific Reports
Status
Peer reviewed
ISSN
2045-2322Type
Journal article
Description
EZ-C acknowledges the University of St Andrews for financial support. We are grateful to the EPSRC for financial support from grant EP/M02105X/1 and the European Research Council for financial support from grant 321305. I.D.W.S. acknowledges a Royal Society Wolfson Research Merit Award.Collections
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