Wavelength-selective porphyrin photodiodes via control of Soret- and Q-band absorption

• Published in: Dyes and pigments Vol. 193; p. 109531
• Main Authors: Bernardini, Martina Shasa, Kim, Juhee, Kim, Hyeokjun, Song, Minkyu, Jang, Woo-Dong, Chung, Dae Sung, Jung, In Hwan
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2021
• Subjects: Detectivity; Photodetectors; Photodiodes; Porphyrins; Wavelength selectivity; Detectivity; Photodetectors; Photodiodes; Wavelength selectivity; Porphyrins
• ISSN: 0143-7208; 1873-3743
• DOI: 10.1016/j.dyepig.2021.109531

Porphyrin-based photodiode materials have mainly been targeted to achieve panchromatic absorption by maximizing the Soret- and Q-band absorption; however, they have rarely been studied with the purpose to make them wavelength-selective in photodetecting devices. In this study, we synthesized a wavelength-selective porphyrin material, PZn-FL, via Sonogashira coupling between an ethyne π-linked porphyrin core (PZn) and four fluorene (FL) moieties. The synthesized PZn-FL material showed a narrow full-width-at-half-maximum (FWHM) of 75 nm in the blue absorption region. The Q-band absorption of PZn-FL was significantly suppressed in organic photodiodes (OPDs), resulting in a blue-selective specific detectivity spectrum with a FWHM of 75 nm and a noise equivalent power of 2.86 × 10−12 W/Hz0.5. The planar backbone structure of PZn-FL was beneficial to increase charge transport and reduce bimolecular recombination, and the vertically oriented alkyl side chains of the PZn backbone contributed to prevent severe intermolecular aggregation and maintain a narrow absorption in film state. [Display omitted] •We synthesized a wavelength-selective porphyrin material, PZn-FL.•PZn-FL showed a narrow full-width-at-half-maximum (FWHM) of 75 nm in film states.•A blue-selective specific detectivity with a FWHM of 75 nm was also achieved in OPDs.•The planar backbone of PZn-FL with vertically oriented alkyl side chains was key structure.