Silicon Analogues of Polyfluorene as Materials for Organic Electronics

Abstract

Poly(dibenzosilole)s have been increasingly reported as an alternative to polyfluorene in organic electronic materials. Poly(dibenzosilole)s show similar optical properties to polyfluorene, but with improved resistance to oxidation and thermal stability. Several poly(dibenzosilole)s and their co-polymers have been incorporated into organic electronic devices, such as light emitting diodes and solar cells. These materials have shown improved performance over their polyfluorene-based counterparts.

Marriage of heavy main group elements with π-conjugated materials for optoelectronic applications

“…Initial motivation for examining these species was to determine if significant Si-R σ*/C=C π* orbital mixing could transpire to lower the LUMO state and the overall electronic band gap in relation to organic cyclopentadienes. 46 While both monomeric and polymeric siloles (and their structural analogues) are still being explored as viable constructs for photovoltaic and TFT applications [47][48][49] there has been a surge in interest in arylated siloles, such as hexaphenylsilole Ph 4 C 4 SiPh 2 , due to their ability to show aggregation-induced emission (AIE) of visible light. In AIE, molecular rotations that normally facilitate non-radiative decay in the excited state are suppressed by the aggregationinduced restriction of molecular motion.…”

Microwave-Assisted Synthesis of an Alternant Poly(fluorene–oxadiazole). Synthesis, Properties, and White Light-Emitting Devices

“…Looking at the absorption band, it can be remarked that the poly(fluorene–oxadiazole) has a sharper profile compared to that of the polyfluorene, suggesting less conformational isomers in solution in concordance with a better conjugation and consequently with a higher stiffness of the polymeric chains [44]. Applying the energy equation of quantum mechanics to the wavelength corresponding to the absorption maximum (384 nm), the value of the optical bandgap of the POF molecules was calculated to be 3.22 eV compared to 3.31 eV found for PF [45]. The decreasing of the HOMO–LUMO energy by conjugation of the directly connected electron withdrawing oxadiazole with the electron donating fluorene was obvious.…”

Silicon and Oxygen Synergistic Effects for Discovery of New High-Performance Nonfullerene Acceptors

“…Taking the advantages of silicon and oxygen atom-doping in the design of the high performance organic semiconductors, development of 6-membered silicon-oxygen-bridged (SiO-bridged) π-conjugated skeletons to investigate the synergistic effects of Si and O atoms in organic electronics is highly appealing and would significantly enhance the structural diversity of π-conjugated materials and improve the performance in a wide range of optoelectronic technologies. However, even diverse 5-membered siliconbridged π-systems such as siloles, dibenzosiloles, dithienosiloles and related compounds have been synthesized and widely utilized in organic electronics (Figure 1b) [32][33][34][35][36][37][38][39][40][41][42][43] , until now, investigations on 6membered SiO-bridged π-conjugated materials are inherently limited with the narrow structural diversity, presumably mainly because of the challenges in their synthesis.…”