Researchers have demonstrated that tiny concentric nanocircles self-assemble into an optical material with precision and efficiency. Electron microscopy and x-ray scattering revealed the structure and spatial distribution of each ingredient in the resulting materials. The new findings could enable the large-scale manufacturing of multifunctional nanocomposites. Read more »
ALS Work Using RSoXS
Resonant soft x-ray scattering (RSoXS) combines conventional small-angle x-ray scattering (SAXS) with soft x-ray absorption spectroscopy (XAS) for a chemically sensitive structure probe that unambiguously deciphers the complex morphologies of mesoscale materials. The scattering contributions from the different components can be selectively enhanced by tuning the x-ray photon energy to match the absorption spectrum of different chemical components. RSoXS has been applied to structured polymer assemblies, organic electronics, functional nanocomposites, liquid crystals, and bio/biohybrid materials.
Synergistic Engineering of Side Chains and Backbone Regioregularity of Polymer Acceptors for High-Performance All-Polymer Solar Cells with 15.1% Efficiency
Researchers developed a series of polymer acceptors with controlled backbone regioregularities and side chain structures. All-polymer solar cells based on a RRg-C20 acceptor which has a regioregular backbone and optimal side chain length achieve a high power conversion efficiency of 15.12%, attributed to high electron mobility and optimal blend morphology. Read more »
Label-Free Characterization of Organic Nanocarriers
A technique developed at the ALS enables accurate characterization of organic nanocarriers (molecules that encapsulate other molecules) without the need for disruptive labeling. The method will enable faster, more precise development of exciting new technologies, ranging from targeted drug delivery to oil-spill remediation. Read more »
Efficient Organic Solar Cell with 16.88% Efficiency Enabled by Refined Acceptor Crystallization and Morphology with Improved Charge Transfer and Transport Properties
Feng Liu and co‐workers report a detailed structure‐performance relationship to help understand the success of Y6 non‐fullerene acceptors. Through the analysis of the single crystal structure of Y6, it is found that Y6 forms a polymer‐like conjugated backbone through its banana‐shaped structure and π‐π interactions between molecules, and forms a 2D electron transport network under the ordered arrangement of the lattice. Read more »
Multiple Levels of Chirality from Achiral Molecules
Liquid crystal samples were found to exhibit up to four levels of chirality, despite being made up of achiral molecules. The work sheds light on how molecular properties and competing interactions “propagate” order from the molecular level up to the microscale, leading to complexity similar to that found in biological materials. Read more »
Chemical and Morphological Origins of Improved Ion Conductivity in Perfluoro Ionene Chain Extended Ionomers
Resonant x-ray scattering and x-ray absorption spectroscopy with elemental sensitivity unravel structural features tied to water–ion domains and discern sulfur-containing groups in sulfonated ionomers, which help delineate chemical factors controlling their phase-separated morphology and governing ion transport. Read more »
Sulfur-linked cyanobiphenyl-based liquid crystal dimers and the twist-bend nematic phase
The synthesis and characterization of cyanobiphenyl-based liquid crystal dimers containing sulfur links between the spacer and mesogenic units are described. Resonant x-ray scattering studies of the twist-bend nematic phase at both the carbon and sulfur absorption edges were performed to determine the critical behaviour of the helical pitch at the transition to the nematic phase. Read more »
Linking Structure to Behavior in Twisted Liquid Crystals
Researchers untangled connections between structure and behavior in a class of liquid crystals consisting of flexible, chain-like molecules that self-organize into twisting patterns. The study opens up new possibilities for designing novel liquid-crystal molecules that allow greater control of nanoscale behavior for technological applications. Read more »
Rational Optimization of Organic Solar-Cell Materials
Researchers have established a new quantitative model that connects molecular interactions in organic solar-cell materials to device performance. The work suggests a way to quickly identify ideal material mixtures and processing methods, bypassing trial-and-error strategies and minimizing labor-intensive synthesis. Read more »
Twisted Structures Emerge from Achiral Molecules
The spontaneous formation of chiral structures from achiral molecules could shed light on the origin of biological homochirality—how one type of chirality dominated the other in certain biological molecules. Here, resonant soft x-ray scattering (RSoXS) has been used to explore helical phases that emerge from achiral asymmetric dimers. Read more »