Synthesis of D–A polymers with a disilanobithiophene donor and a pyridine or pyrazine acceptor and their applications to dye-sensitized solar cells

Abstract

New donor-acceptor polymers containing disilanobithiophene (DSBT) as the donor and pyridine or pyrazine as the acceptor with or without a thiophene spacer were prepared. The polymers showed UV-vis absorption maxima at λmax = 488-526 nm, which were red-shifted relative to those of model monomers dithienylpyridine and dithienylpyrazine (λmax = 352-375 nm), indicating the efficient conjugation along the polymer chains. A homo polymer of DSBT was also prepared. The DSBT-10 containing polymers were attached to TiO2 electrodes by immersing the electrodes in the polymer solutions under irradiation (> 400 nm) or in the dark. The modified electrodes were applied to dyesensitized solar cells and a maximal power conversion efficiency of 0.89% was obtained using the TiO2 electrode thermally modified with a DSBT-pyrazine alternating polymer.

Tailored Assembly of Molecular Water Oxidation Catalysts on Photoelectrodes for Artificial Photosynthesis

“…Despite such efforts, the immobilization of molecular organometallic electrocatalysts through modification of their ligand molecules cannot avoid degradation of catalytic activity. This can be attributed to (1) the degradation of catalytic activity after the introduction of functional groups, leading to changes in electron distribution and energetics in electrocatalysts,, , and (2) the vulnerability of ester linkages to hydrolytic degradation, resulting in detachment of electrocatalysts from photoelectrodes , . It is well‐known that the introduction of electron withdrawing and donating groups has a significant effect on their redox potentials and catalytic activity , , .…”

“…This can be attributed to (1) the degradation of catalytic activity after the introduction of functional groups, leading to changes in electron distribution and energetics in electrocatalysts, [95,127,128] and (2) the vulnerability of ester linkages to hydrolytic degradation, resulting in detachment of electrocatalysts from photoelectrodes. [95,127] It is well-known that the introduction of electron withdrawing and donating groups has a significant effect on their redox potentials and catalytic activ- Reproduced from ref. [137] (e) Schematic illustration and (f) performance of dye-sensitized PEC cells fabricated by covalent immobilization of molecular photosensitizers and electrocatalysts.…”

Synthesis of a Conjugated D-A Polymer with Bi(disilanobithiophene) as a New Donor Component

“…Figure 2 shows the UV absorption spectra of pDSBT2-BT in solution and film, and Table 1 summarizes the data of pDSBT2-BT and those of pDSBT-BT [12] and homopolymer pDSBT [14] reported previously ( Figure 3). Figure 2 shows the UV absorption spectra of pDSBT2-BT in solution and film, and Table 1 summarizes the data of pDSBT2-BT and those of pDSBT-BT [12] and homopolymer pDSBT [14] reported previously ( Figure 3). to be Mn = 13,000 (Mw/Mn = 1.9), relative to polystyrene standards.…”

“…Polymer synthesis. Figure 2 shows the UV absorption spectra of pDSBT2-BT in solution and film, and Table 1 summarizes the data of pDSBT2-BT and those of pDSBT-BT [12] and homopolymer pDSBT [14] reported previously ( Figure 3). to be Mn = 13,000 (Mw/Mn = 1.9), relative to polystyrene standards.…”

“…Polymer synthesis. Figure 2 shows the UV absorption spectra of pDSBT2-BT in solution and film, and Table 1 summarizes the data of pDSBT2-BT and those of pDSBT-BT [12] and homopolymer pDSBT [14] reported previously (Figure 3). The absorption was shifted to the longer wavelength region when the spectrum was measured as a film, suggesting enhanced interchain interaction and/or planarity of the polymer in film.…”