Long-wavelength visible to near infrared photoluminescence from carbon-bridged styrylstilbene and thiadiazole conjugates in organic and aqueous media

• Published in: RSC advances Vol. 11; no. 11; pp. 68 - 613
• Main Authors: Inoue, Takeru, Tsurui, Makoto, Yamagishi, Hiroshi, Nakazawa, Yuma, Hamaguchi, Naoto, Watanabe, Shoya, Kitagawa, Yuichi, Hasegawa, Yasuchika, Yamamoto, Yohei, Tsuji, Hayato
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 03-02-2021; The Royal Society of Chemistry
• Subjects: Aqueous solutions; Carbon; Chemistry; Conjugates; Cyclohexane; Photoluminescence; Solvents; Thiadiazoles
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d0ra10201f

Donor-acceptor-donor conjugates composed of electron-donating carbon-bridged styrylstilbene (COPV2) and electron-accepting thiadiazole derivatives equipped with carbazolyl (Cz) terminators,
Cz-COPV2-A-COPV2-Cz
(A = benzothiadiazole (
BTz
), naphthobis(thiadiazole) (
NTz
), or benzobis(thiadiazole) (
BBTz
)), were newly synthesized and found to serve as efficient and stable long-wavelength photoluminescent dyes in organic and aqueous media. In particular,
Cz-COPV2-BBTz-COPV2-Cz
showed photoluminescence in the near infrared region (895-927 nm) with a photoluminescence quantum yield (PLQY) of up to 0.19 in cyclohexane and of 0.02-0.03 in THF/water mixtures. Its analogues with weaker acceptors,
Cz-COPV2-BTz-COPV2-Cz
and
Cz-COPV2-NTz-COPV2-Cz
, showed yellow to deep-red emission in organic solvents, with PLQYs of up to 0.71 in organic solvents and 0.45 in THF/water mixtures.
Efficient long-wavelength visible to NIR-emitting materials have been synthesized by use of rigid planar styrylstilbene as a donor component.