β-Functionalized push–pull opp-dibenzoporphyrins as sensitizers for dye-sensitized solar cells: the role of the phenylethynyl bridge

Abstract

Push–pull opp-dibenzoporphyrins with a phenylethynyl bridge were newly synthesized as sensitizers for dye-sensitized solar cells, giving power conversion efficiencies up to 6.7%, close to that of the N719 dye under similar conditions.

Synthesis, Spectral, Electrochemical and Photovoltaic Studies of A3B Porphyrinic Dyes having Peripheral Donors

“…Both A 3 B and trans-A 2 BC Zn(II) porphyrin dyes have excited state oxidation potential (E ox *) much higher than the conduction band of the TiO 2 . [48,50] They have driving forces ranging between À 0.46 to À 0.50 V, KP-TriPTZ-Zn showed the highest driving force while RA-199-Zn have the lowest driving force as shown in Table S1 in the SI. On the other hand, the first oxidation potential of all the dyes is more positive 0.56-0.69 V vs. NHE than the redox potential of I À /I 3 À (0.4 V vs. NHE) which depict easy regeneration of dye cation in DSSC process ( Table 3).…”

“…[20,25,28] The highest PCE value of KP-TriPTZ-Zn supports the fact that phenothiazine attached to porphyrin is the best light harvesting and electron donor among the studied groups which is also consistent with reported literature. [20,25,[49][50][51][52][53][54] Electrochemical impedance spectroscopy studies of A 3 B and trans-A 2 BC Zn(II) porphyrin dye modified solar cells were performed to understand the kinetics of charge transfer. [55,56] The Nyquist plot of KP-TriPTZ-Zn and other dyes constructed DSSCs are presented in Figure 6 and Figures S30-S31 in SI, respectively.…”

“…[47] An ideal dye needs to have a driving force for electron injection and dye regeneration if these two processes are going to be thermodynamically feasible. [48,50] They have driving forces ranging between À 0.46 to À 0.50 V, KP-TriPTZ-Zn showed the highest driving force while RA-199-Zn have the lowest driving force as shown in Table S1 in the SI. [48,50] They have driving forces ranging between À 0.46 to À 0.50 V, KP-TriPTZ-Zn showed the highest driving force while RA-199-Zn have the lowest driving force as shown in Table S1 in the SI.…”

“…[20] The PCE values of trans-A 2 BC Zn(II) porphyrin dyes follows the trend: RA-199-Zn (η = 2.4 %) < RA-200-Zn (η = 4.2 %) < RA-195-Zn (η = 4.3 %). [20,25,[49][50][51][52][53][54] Electrochemical impedance spectroscopy studies of A 3 B and trans-A 2 BC Zn(II) porphyrin dye modified solar cells were performed to understand the kinetics of charge transfer. However, while increasing the number of donor groups (KP-TriPYR-Zn, KP-TriCBZ-Zn and KP-TriPTZ-Zn), the efficiency increases drastically due to better electron donating ability of peripheral rich groups.…”

Unprecedented Nucleophilic Attack of Piperidine on the Electron Acceptor during the Synthesis of Push‐Pull Dyes by a Knoevenagel Reaction

“…During the past decades, push‐pull dyes have been extensively studied with regards to their numerous applications ranging from sensors, energy conversion, field effects transistors, organic light‐emitting diodes, nonlinear optics or photoinitiators of polymerization . To access to these structures consisting in an electron donor connected to an electron acceptor by means of a conjugated or none‐conjugated spacer, the Knoevenagel reaction is undoubtedly the most popular reaction, opposing an aldehyde with an electron acceptor bearing an activated methylene group, in the presence of a catalytic amount of a base.…”