The self-assembly of block copolymers with large feature sizes is inherently challenging as the large kinetic barrier arising from chain entanglement of high molecular weight (MW) polymers limits the extent over which long-range ordered microdomains can be achieved. Here, we illustrate the evolution of thin film morphology from a diblock copolymer of polystyrene-block-poly(dimethylsiloxane) exhibiting total number average MW of 123 kg mol, and demonstrate the formation of layers of well-ordered cylindrical microdomains under appropriate conditions of binary solvent mix ratio, commensurate film thickness, and solvent vapor annealing time. Directed self-assembly of the block copolymer within lithographically patterned trenches occurs with alignment of cylinders parallel to the sidewalls. Fabrication of ordered cobalt nanowire arrays by pattern transfer was also implemented, and their magnetic properties and domain wall behavior were characterized.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1088/1361-6528/aa61c9 | DOI Listing |
Nat Chem
January 2025
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
Atomically precise nanoclusters can be assembled into ordered superlattices with unique electronic, magnetic, optical and catalytic properties. The co-crystallization of nanoclusters with functional organic molecules provides opportunities to access an even wider range of structures and properties, but can be challenging to control synthetically. Here we introduce a supramolecular approach to direct the assembly of atomically precise silver nanoclusters into a series of nanocluster‒organic ionic co-crystals with tunable structures and properties.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2024
Wallenberg Wood Science Center, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden; Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden. Electronic address:
Hypothesis: Charge-stabilized colloidal cellulose nanocrystals (CNCs) can self-assemble into higher-ordered chiral nematic structures by varying the volume fraction. The assembly process exhibits distinct dynamics during the isotropic to liquid crystal phase transition, which can be elucidated using X-ray photon correlation spectroscopy (XPCS).
Experiments: Anionic CNCs were dispersed in propylene glycol (PG) and water spanning a range of volume fractions, encompassing several phase transitions.
Small Methods
January 2025
Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, 518055, China.
Recent advances in biomolecular self-assembly have transformed material science, enabling the creation of novel materials with unparalleled precision and functionality. Among these innovations, 3D DNA crystals have emerged as a distinctive class of macroscopic materials, engineered through the bottom-up approach by DNA self-assembly. These structures uniquely combine precise molecular ordering with high programmability, establishing their importance in advanced material design.
View Article and Find Full Text PDFMacromol Rapid Commun
January 2025
School of Materials Science and Engineering, Beihang University, Beijing, 100191, P. R. China.
Polymer cubosomes (PCs) have garnered significant interest in the field of nanomaterials and nanotechnology due to their unique properties and potential applications. However, the fabrication of PCs remains challenging. Polymerization-induced self-assembly (PISA) is recognized as an efficient method for producing a variety of polymer particles, including PCs.
View Article and Find Full Text PDFNano Lett
January 2025
School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China.
Pnictogen bond (PnB) occurring on the group-15 elements is recognized as σ- or π-hole-based interaction that has garnered attention in the fields of anion recognition and organocatalysis. Due to the polyvalent feature of pnictogens and high directionality, PnB possesses potential in the design of convergent coassembled materials with acceptors containing lone pair electrons or anions, which however is rarely explored so far. Herein, we unveil the role of antimony (Sb)-based PnB donors in producing self-assembled chiroptical materials with lone pair electron containing acceptors.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!