Block copolymer morphologies confined by square-shaped particle:Hard and soft confinement

The self-assembly of diblock copolymers confined around one square-shaped particle is studied systematically within two-dimensional self-consistent field theory（SCFT）.In this model,we assume that the thin block copolymer film is confined in the vicinity of a square-shaped particle by a homopolymer melt,which is equivalent to the poor solvents.Multiple sequences of square-shaped particle-induced copolymer aggregates with different shapes and self-assembled internal morphologies are predicted as functions of the particle size,the structural portion of the copolymer,and the volume fraction of the copolymer.A rich variety of aggregates are found with complex internal self-assembled morphologies including complex structures of the vesicle,with one or several inverted micelle surrounded by the outer monolayer with the particle confined in the core.These results demonstrate that the assemblies of diblock copolymers formed around the square-shaped particle in poor solvents are of immediate interest to the assembly of copolymer and the morphology of biomembrane in the confined environment,as well as to the transitions of vesicles to micelles.

Hierarchical Microphase Behaviors of Chiral Block Copolymers under Kinetic and Thermodynamic Control

Chiral superstructures in confined spaces are subtly affected by the complex interplay among various noncovalent interactions,details of which are still in adequately understood.Herein,we report the threedimensional confined assembly of the chiral block copolymers of polystyrene-block-poly(D-lactide)andits enantiomer in emulsion droplets and demonstrate unprecedented successive microphase transformations from single helices to double helices with inverted helicity,and then to twisted cylinders in the constructedcolloidal particles.Theabovehierarchical structural transformations of chiral microphases are kinetically dependent and can further transform into thermodynamically stable achiral cylinders with saddle-shaped topology upon solvent annealing.The formation and subsequent structural transformations as well as thefinal degeneration of chiral architectures provide guidance to understand the chiral evolution at different length scales within spherical confined space and to fabricate biomimetic systems.

One-step synthesis of hierarchical Ni_(3)Se_(2)nanosheet-on-nanorods/Ni foam electrodes for hybrid supercapacitors

Transitional metal selenides have high conductivity,even metal quality,which makes them great for using as electrode materials for fabricating supercapacitors.Here,hierarchical Ni_(3)Se_(2)nanosheet-on-nanorods on Ni foam(NSR-Ni_(3)Se_(2)/Ni)was fabricated by a facile three-dimensional(3D)substrate-assisted confinement assembly method,and used as a freestanding electrode material for hybrid supercapacitors(HSCs).In this design,metallic Ni_(3)Se_(2)with hybrid 1D/2D architecture could effectively enhance the active specific surface area of electrode and improve space utilization,as well as significantly facilitate electrons transport,while Ni foam served as the Ni source of Ni_(3)Se_(2)and provided 3D multi-electron transport channels,thus boosting the specific capacity.The constructed hierarchical NSR-Ni_(3)Se_(2)electrode delivered a superior areal specific capacity of 1.068 mAh/cm^(2)(7.69 F/cm^(2))at 2 mA/cm^(2)and retained 68.2%of the initial capacity when the current density increases by 15 times.Furthermore,the as-assembled NSR-Ni_(3)Se_(2)device exhibited an ultrahigh energy density of 56.4 Wh/kg and high power density of 4640.3 W/kg,and a capacity retention of 92.6%even after 6000 cycles.