Molecular Design Rule of Phthalocyanine Dyes for Highly Efficient Near‐IR Performance in Dye‐Sensitized Solar Cells

Abstract

A series of zinc-phthalocyanine sensitizers (PcS16-18) with different adsorption sites have been designed and synthesized in order to investigate the dependence of adsorption-site structures on the solar-cell performances in zinc-phthalocyanine based dye-sensitized solar cells. The change of adsorption site affected the electron injection efficiency from the photoexcited dye into the nanocrystalline TiO2 semiconductor, as monitored by picosecond time-resolved fluorescence spectroscopy. The zinc-phthalocyanine sensitizer PcS18, possessing one carboxylic acid directly attached to the ZnPc ring and six 2,6-diisopropylphenoxy units, showed a record power conversion efficiency value of 5.9 % when used as a light-harvesting dye on a TiO2 electrode under one simulated solar condition.

Asymmetric zinc phthalocyanines with large steric hindrance as efficient red/near-IR responsive sensitizer for dye-sensitized solar cells

“…Zn-tri-PcNc-4 exhibits much higher IPCE values in the red/near-IR region (especially in 550e770 nm) than Zn-tri-PcNc-5, also implying Zn-tri-PcNc-4 would contribute higher photocurrent than Zn-tri-PcNc-5. Moreover, the maximum IPCE value of Zn-triPcNc-4/Zn-tri-PcNc-5 is redshifted by~11/62 nm compared to that (699 nm) of Zn-tri-PcNc-2 [12,13], suggesting a difference in the "pushepull" balance in the ZnPc ring due to the three tert-butyl groups in Zn-tri-PcNc-2 replaced by six bulky electron-donating groups with larger steric hindrance in Zn-tri-PcNc-4/Zn-triPcNc-5, which could further influence the electronic interaction between the Pc ring and the TiO 2 owing to the adsorption of the carboxylic onto TiO 2 surface, and then the electron transfer from ZnPc excited singlet state to TiO 2 CB [15,16].…”

“…The naphtha part linked by a carboxyl group can extend the red/near-IR absorption of the ZnPc derivative [12e14], while the use of the bulky electron-pushing groups have been proven to be the best compromise to get Pc dyes with good solubility and low molecule aggregates [15], and the intramolecular pushepull character afforded by the electrondonating/withdrawing groups would be anticipated to make efficient electron transfer from the excited ZnPc molecules to TiO 2 CB [9,16]. Moreover, Q-band redshift can be achieved by introducing S atoms instead of O atoms in the six electron-donating substituents.…”

Water soluble quarternizable gallium and indium phthalocyanines bearing quinoline 5-sulfonic acid: Synthesis, aggregation, photophysical and electrochemical studies

“…In recent years, many efforts to make the best specified molecular materials aredevoted on chemical sensors [4][5][6], semiconductors [7], electrochromic display devices [8][9][10], liquid crystals [11,12], solar cells [13], photovoltaics [14] various catalytic processes [15,16] and photosensitizers [17,18]. Phthalocyanines well known to possess the photosensitizer activity are commonly used in PDT (photodynamic cancer therapy) because of their absorptions inthe red region [19].…”

Synthesis, characterization and investigation of the spectroscopic properties of novel peripherally 2,3,5-trimethylphenoxy substituted Cu and Co phthalocyanines, the computational and experimental studies of the 4-(2,3,5-trimethylphenoxy)phthalonitrile

“…A minimum amount of 80.000 tons of Pcs are produced per year just for this purpose [3]. They have been also used in other applications such as liquid crystals [4,5], optical applications [6,7], HIV inactivation [8,9], electrochromism [10,11], molecular solar cells [12,13], chemical sensors [13,14], semiconductors for organic field-effect transistors [16,17], and photodynamic therapy [18,19,20].…”

“…Then UV-Vis spectra of these compounds were recorded in different solvents and different concentrations. Furthermore, molecular geometry parameters, vibrational frequencies and 1 H, 13 C NMR chemical shift values of the 4-(2,3,5-trimethylphenoxy)phthalonitrile, which was reported the crystal structure of which was reported by our group in previous paper [29], were calculated and compared with the experimental specifications.…”