The structural and optoelectronic properties of mixed halide perovskite colloidal precursor dispersions are investigated. With increasing concentration, we observe four stages of growing structures, which affect the thin film morphology: (I) nanoparticles, (II) increasing size of nanoparticles, (III) formation of large aggregates/complex clusters and (IV) fragmentation of large
[email protected]12 March 2021
Aqueous redox flow batteries using electroactive organic materials are currently attracting significant attention. However, the influence of supporting electrolytes on the aqueous solubility, electrochemical reversibility and chemical stability of the organic components has rarely been investigated. Here, a new electrolyte design strategy towards enhanced solubility and chemical stability of
[email protected]12 March 2021
The modulation of structural fibrous protein and polysaccharide biopolymers for the design of biomaterials is still relatively challenging due to the non-trivial nature of the transformation from a biopolymer's native state to a more usable form. To gain insight into the nature of the molecular interaction between silk and cellulose…
[email protected]12 March 2021
Transition metal chalcogenides with layered structures have emerged as promising materials for energy storage, catalysis, and electronics, among other areas. We have identified a new layered phase of iron sulfide containing interlayer solvated cations. We present an optimized synthesis for the Li+-containing material from an Fe(III) xanthate complex. Structure and…
[email protected]12 March 2021
Printing of active layers of high-efficiency organic solar cells and morphology control by processing with varying solvent additive concentrations are important to realize real-world use of bulk-heterojunction photovoltaics as it enables both up-scaling and optimization of the device performance. In this work, active layers of the conjugated polymer with benzodithiophene…
[email protected]12 March 2021
The rheological spectra of poly(n-butyl acrylate) in the presence of a series of P(nBA-b-HEMA) rheology modifiers show a two-step relaxation process originating from the PnBA matrix and the self-assemblies. The HEMA segments are further grafted with strong, hydrogen bonding UPy groups, which both magnifies and slows down the relaxation of…
[email protected]12 March 2021
Large-pore ordered mesoporous silica (OMS) COK-12, analogous to the well-known SBA-15, but synthesized in a more environmentally friendly way and exhibiting a shorter plate-like structure, was grafted with different amounts of graphene oxide (GO) for the first time in an inexpensive and rapid process, that was successfully upscaled. Samples were…
[email protected]12 March 2021
Polymer crystals that are good conductors of heat are highly desirable for thermal management applications. Although thermally conductive polymer crystals are well known, the microscopic thermal transport processes that enable these properties have been challenging to probe experimentally. We used an optical method to probe heat conduction at submicrometer length…
[email protected]5 March 2021
We report the fabrication, properties, and bacteria-resistance of polyelectrolyte complex (PEC) coatings and free-standing films. Poly(4-styrenesulfonic acid), poly(diallyldimethylammonium chloride), and salt were spin-coated into PEC films. After thermal annealing in a humid environment, highly transparent, mechanically strong, and chemically robust films were formed. Notably, we demonstrate
sergio.rodrigue[email protected]27 January 2020
We investigated the two-step chemical transformation of a series of symmetric poly(styrene-b-solketal acrylate) (PS-b-PSA) copolymers with varying molecular weights from 1900 to 27?300 g/mol (13 ? N ? 194) synthesized by sequential atom transfer radical polymerization. Through acid-catalyzed hydrolysis, the PSA block is converted into poly(glycerol acrylate) (PGA), which subsequently…
[email protected]27 January 2020