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In this study, we demonstrated for the first time that a metal-containing semicrystalline polymer was used as an additive to mediate the thin film morphology of solution-grown, small-molecule organic semiconductors. By mixing polyferrocenylsilane (PFS) with an extensively-studied organic semiconductor 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene), PFS as a semicrystalline polymer independently forms nucleation and crystallization while simultaneously ameliorating diffusivity of the blend system and tuning the surface energies as a result of its partially amorphous property. We discovered that the resultant blend film exhibited a 6-fold reduction in crystal misorientation angle and a 3-fold enlargement in average grain width. Enhanced crystal orientation considerably reduces mobility variation, while minimized defects and trap centers located at grain boundaries lessen the adverse impact on the charge transport. Consequently, bottom-gate, top-contact organic thin film transistors (OTFTs) based on the TIPS pentacene/PFS mixture yielded a 40% increase in performance consistency (represented by the ratio of average mobility to the standard deviation of mobility). The PFS semicrystalline polymer-controlled crystallization can be used to regulate the thin film morphology of other high-performance organic semiconductors and shed light on applications in organic electronic devices.

Abstract: Chemical and topographic surface patterning of inorganic polymer‐functionalized nanoparticles (NPs) and their self‐assembly in nanostructures with controllable architectures enable the design of new NP‐based materials. Capping of NPs with inorganic polymer ligands, such as metallopolymers, can lead to new synergetic properties of individual NPs or their assemblies, and enhance NP processing in functional materials. Here, for gold NPs functionalized with polyferrocenylsilane, two distinct triggers are used to induce attraction between the polymer ligands and achieve NP self‐assembly or topographic surface patterning of individual polymer‐capped NPs. Control of polymer–solvent interactions is achieved by either changing the solvent composition or by the electrooxidation of polyferrocenylsilane ligands. These results expand the range of polymer ligands used for NP assembly and patterning, and can be used to explore new self‐assembly modalities. The utilization of electrochemical polymer oxidation stimuli at easily accessible potentials broadens the range of stimuli leading to NP self‐assembly and patterning. [ABSTRACT FROM AUTHOR]

The main block of polyferrocenylsilane (PFS) polymer is composed of ferrocene molecules bridged by silicon atoms. In this study, we found that PFS was insoluble in an imidazolium-based ionic liquid. On the other hand, PFS dissolved easily in an ionic liquid based on pyrazolium, under ordinary conditions and at room temperature. Furthermore, dissolving PFS in this ionic liquid afforded a p-type doped material. We found that the secondary amine in pyrazolium acted as an oxidant for ferrocene, allowing the PFS to dissolve in the ionic liquid. The measured thermal properties of the PFS-ionic liquids allowed us to show the existence of an attractive interaction between PFS and the ionic liquid. [ABSTRACT FROM AUTHOR]

The incorporation of metal atoms into synthetic polymer chains leads to desirable properties and generates a new and versatile class of functional materials with enhanced processability. New creative approaches have led to macromolecular structures in which metals are not only incorporated via the use of traditional covalent bonds but also by potentially reversible coordination interactions. Metallopolymers with precisely controlled chain length are therefore attracting rapidly expanding attention as a result of their properties and potential applications. This article focuses on polyferrocenylsilanes and polyferrocenylsilane block copolymers where iron and silicon are present in the main chain of the organometallic segment. These materials also represent an area of rapidly growing interest as a result of their self-assembly. The resulting nanostructured materials have a wealth of potential applications and recent breakthroughs in this area are discussed. The subject matter of the article is divided up into subsections covering polyferrocenylsilane homopolymer and block copolymer synthesis, solution and solid state self-assembly, and applications. [ABSTRACT FROM AUTHOR]

Two polyferrocenylsilanes (PFSs) 1 and 2 with aniline and carbazolyl as side chains have been prepared by treating silyl-chloride functionalized PFS (PFS-Cl) with hydroxyl-ended aniline and carbazole compounds, respectively, and characterized by NMR, FT-IR, elemental analysis (EA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and cyclic voltammetry (CV). Both of them could be oxidized by iodine and 2,3-dichloro-5,6-dicyanoquinone (DDQ) to form complexes. PFS 1 could be oxidized by tetracyanoethylene (TCNE) too. The complexes are characterized by FT-IR, EA, Iron-57 Mössbauer spectroscopy. All of them are partially oxidized by the oxidants and both Fe and Fe coexist in the complexes. Magnetic property measurement by superconducting quantum interference device (SQUID) shows their paramagnetic properties with somewhat antiferromagnetic interaction. Results show that the joint type between PFS backbone and the electron-rich side groups has less direct effect on the exhibition of ferromagnetic interaction in their complexes. [ABSTRACT FROM AUTHOR]

In this study, we demonstrated for the first time that a metal-containing semicrystalline polymer was used as an additive to mediate the thin film morphology of solution-grown, small-molecule organic semiconductors. By mixing polyferrocenylsilane (PFS) with an extensively-studied organic semiconductor 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene), PFS as a semicrystalline polymer independently forms nucleation and crystallization while simultaneously ameliorating diffusivity of the blend system and tuning the surface energies as a result of its partially amorphous property. We discovered that the resultant blend film exhibited a 6-fold reduction in crystal misorientation angle and a 3-fold enlargement in average grain width. Enhanced crystal orientation considerably reduces mobility variation, while minimized defects and trap centers located at grain boundaries lessen the adverse impact on the charge transport. Consequently, bottom-gate, top-contact organic thin film transistors (OTFTs) based on the TIPS pentacene/PFS mixture yielded a 40% increase in performance consistency (represented by the ratio of average mobility to the standard deviation of mobility). The PFS semicrystalline polymer-controlled crystallization can be used to regulate the thin film morphology of other high-performance organic semiconductors and shed light on applications in organic electronic devices. [ABSTRACT FROM AUTHOR]

Mixed micelles formed by co‐assembly of pairs of block copolymers (BCPs) can develop novel morphologies and generate useful properties not accessible from homomicelles. For micelles consisting of two different polymers in the corona, identifying the location of the corona chains is a critical part of morphology characterization. Coronal segregation in mixed micelle is often characterized by transmission electron microscopy in combination with selective staining of individual polymers. In this study, Karstedt's catalyst is used for selective Pt(0)‐olefin coordination staining of polyisoprene (PI) and poly(methylvinylsiloxane) (PMVS) corona chains in the presence of poly(dimethylsiloxane) (PDMS) corona chains in cylindrical mixed micelles with a crystalline poly(ferrocenyldimethylsilane) (PFS) core. Previous experiments using OsO4 as a stain did not enable visualization of nanoscale coronal segregation in mixed micelles obtained from co‐assembly of PFS‐b‐PI and PFS‐b‐PDMS, as well as PFS‐b‐PMVS and PFS‐b‐PDMS. Karstedt's catalyst can be used as a staining agent for visualizing nanoscale coronal segregation in core‐crystalline comicelles through Pt(0)‐olefin coordination. [ABSTRACT FROM AUTHOR]