No abstract

We herein report the tunable self-assembly of simple block copolymers, namely polystyrene-block-poly(ethylene oxide) (PS-b-PEO) diblock copolymers, into porous cubosomes with inverse Im3‾m or Pn3‾m mesophases of controlled unit cell parameters as well as hexasomes with an inverse hexagonal (p6mm) structure, which have been rarely observed in polymer self-assembly. A new morphological phase diagram was constructed for the solution self-assembly of PS-b-PEO based on the volume fraction of the PS block against the initial copolymer concentration. The formation mechanisms of the cubosomes and hexasomes have also been revealed. This study not only affords a simple system for the controllable preparation and fundamental studies of ordered bicontinuous structures, but also opens up a new avenue towards porous architectures with highly ordered pores.

This paper reports facile synthesis of nitrogen-doped mesoporous carbon nanospheres (MCNSs) with average diameters of around 300 nm and well-controlled pore sizes ranging from 8 to 38 nm, by employing polystyrene-b-poly(ethylene oxide) (PS-b-PEO) diblocks with different PS block lengths as the soft templates and dopamine as the carbon-rich precursor. For the first time, a linear equation is achieved for the quantitative control of the average pore size of MCNSs by simply adjusting a block length of diblock copolymer. The resultant MCNSs possess high surface areas of up to 450 m(2) g(-1) and nitrogen doping contents of up to ≈3 wt%. As electrode materials of supercapacitors, the MCNSs exhibit excellent electrochemical performance with high specific capacitances of up to 350 F g(-1) at 0.1 A g(-1) , superior rate capability, and cycling stability. Interestingly, the specific capacitance of the MCNSs reduces linearly with increasing pore size, whereas the normalized capacitance by specific surface area remains invariable. This represents a new spectrum of the relationship between electrochemical capacitance and pore size (>5 nm) for porous carbons, which makes a complement to the existing spectra focusing on pore diameters of <5 nm.

Free-standing 2D porous nanomaterials have attracted considerable interest as ideal candidates of 2D film electrodes for planar energy storage devices.N evertheless,t he construction of well-defined mesopore arrays parallel to the lateral surface,w hichf acilitate fast in-plane ionic diffusion, is achallenge.Now,auniversal interface self-assembly strategy is used for patterning 2D porous polymers,f or example, polypyrrole,p olyaniline,a nd polydopamine,w ith cylindrical mesopores on graphene nanosheets.T he resultant 2D sandwich-structured nanohybrids are employed as the interdigital microelectrodes for the assembly of planar micro-supercapacitors (MSCs), whichd eliver outstanding volumetric capacitance of 102 Fcm À3 and energy density of 2.3 mWh cm À3 , outperforming most reported MSCs.T he MSCs display remarkable flexibility and superior integration for boosting output voltage and capacitance.

Linking blue phosphorene subunits with gold atoms, we grow two-dimensional metal-phosphorus network with good long-range order and better endurance at elevated temperature by molecular-beam epitaxy. We show the possibility to apply the concept of module assembly derived from organic porous networks to an inorganic system.