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The dilemma of employing high-capacity battery materials and maintaining the electronic and mechanical integrity of electrodes demands novel designs of binder systems. Here, we developed a binder polymer with multifunctionality to maintain high electronic conductivity, mechanical adhesion, ductility, and electrolyte uptake. These critical properties are achieved by designing polymers with proper functional groups. Through synthesis, spectroscopy, and simulation, electronic conductivity is optimized by tailoring the key electronic state, which is not disturbed by further modifications of side chains. This fundamental allows separated optimization of the mechanical and swelling properties without detrimental effect on electronic property. Remaining electronically conductive, the enhanced polarity of the polymer greatly improves the adhesion, ductility, and more importantly, the electrolyte uptake to the levels of those available only in nonconductive binders before. We also demonstrate directly the performance of the developed conductive binder by achieving full-capacity cycling of silicon particles without using any conductive additive.

This work demonstrates that the donor-acceptor-donor charge-transfer chromophores can be tailor-made to be near-infrared absorbing and fluorescent, as well as being liquid crystals. The chromophore containing an extremely strong acceptor of benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole) can form a columnar mesophase that absorbs at 890 nm and emits at 1160 nm in the solid state. These chromophores are readily soluble in common organic solvents and can form thin films by casting or spin coating, making them suitable for further device applications.

[reaction: see text] Redox-active dinuclear ruthenium complexes with various 1,2-dicarbonylhydrazido (DCH) ligands are designed and prepared to have intense absorption in the near-infrared region for potential optical sensing in aqueous media, as demonstrated for sensing hydrogen peroxide in this study.

Submonolayer thin films of a three-ring bent-core (or banana-shaped) compound, m-bis(4-n-octyloxystyryl)benzene (m-OSB), were vacuum-deposited on a mica surface, and a spontaneous transition from monolayer films to bilayer crystals was observed at room temperature, which was ascribed to the specific molecular shape and polar layered packing of the bent-core molecules [Tang et al. J. Phys. Chem. B 2004, 108 (34), 12921-12926]. The crystal nucleation and growth from the monolayer films as well as the melting phase transition from the bilayer crystals were investigated using atomic force microscopy (AFM). It was shown that after initial nucleation, the crystal growth was achieved through three pathways: direct absorption of molecules from monolayer films, molecular cluster diffusion, and quasi-Ostwald ripening. When annealing the bilayer crystals at elevated temperatures, morphological change from a bilayer to a monolayer was observed, and some new islands with fingerlike patterns were formed during this process, which resulted from a diffusion-controlled growth of the molten molecules. In general, the high-resolution AFM in combination with the molecularly thin m-OSB films provided us with direct visualization of nucleation, crystal growth, melting, and film morphology evolution on the mesoscopic scale, which are of fundamental interest from the theoretical viewpoint and are of central importance for the control of interfacial properties in practical applications.