6 research outputs found
Thermosensitive ZrP-PNIPAM Pickering Emulsifier and the Controlled-Release Behavior
Asymmetric
Janus and Gemini ZrP-PNIPAM monolayer nanoplates were obtained by
exfoliation of two-dimensional layered ZrP disks whose surface was
covalently modified with thermosensitive polymer PNIPAM. The nanoplates
largely reduced interfacial tension (IFT) of the oil/water interface
so that they were able to produce stable oil/water emulsions, and
the PNIPAM grafting either on the surface or the edge endowed the
nanoplates rapid temperature responsivity. The ZrP-PNIPAM nanoplates
proved to be thermosensitive Pickering emulsifiers for controlled-release
applications
Thermosensitive ZrP-PNIPAM Pickering Emulsifier and the Controlled-Release Behavior
Asymmetric
Janus and Gemini ZrP-PNIPAM monolayer nanoplates were obtained by
exfoliation of two-dimensional layered ZrP disks whose surface was
covalently modified with thermosensitive polymer PNIPAM. The nanoplates
largely reduced interfacial tension (IFT) of the oil/water interface
so that they were able to produce stable oil/water emulsions, and
the PNIPAM grafting either on the surface or the edge endowed the
nanoplates rapid temperature responsivity. The ZrP-PNIPAM nanoplates
proved to be thermosensitive Pickering emulsifiers for controlled-release
applications
Aqueous Exfoliation of Graphite into Graphene Assisted by Sulfonyl Graphene Quantum Dots for Photonic Crystal Applications
We
investigate the π–π stacking of polyaromatic hydrocarbons
(PAHs) with graphene surfaces, showing that such interactions are
general across a wide range of PAH sizes and species, including graphene
quantum dots. We synthesized a series of graphene quantum dots with
sulfonyl, amino, and carboxylic functional groups and employed them
to exfoliate and disperse pristine graphene in water. We observed
that sulfonyl-functionalized graphene quantum dots were able to stabilize
the highest concentration of graphene in comparison to other functional
groups; this is consistent with prior findings by pyrene. The graphene
nanosheets prepared showed excellent colloidal stability, indicating
great potential for applications in electronics, solar cells, and
photonic displays which was demonstrated in this work
Chiral Photonic Crystalline Microcapsules with Strict Monodispersity, Ultrahigh Thermal Stability, and Reversible Response
Tunable photonic
crystals (TPCs) reflecting selected wavelengths of visible light and
responding to external stimuli are widely applied to fabricate smart
optical devices. Chiral nematic liquid crystals (CNLCs) possessing
response to temperature, electric field, and magnetic field are considered
as one-dimensional TPCs. The encapsulation of CNLCs provides responsive
photonic devices with stand-alone macroscopic structure and excellent
processability. However, when CNLCs as cores are wrapped by polymeric
shells to form core–shell structured microcapsules, the polydispersity
of microcapsule size, the irregular spatial geometry, and the low
thermal stability inevitably result in a deterioration of the optical
performance and limited application at high temperatures. Herein,
a combination of microfluidic emulsification and interfacial polymerization
is employed to fabricate polymer wrapped photonic crystalline microcapsules
(PWPCMs). The sizes and reflected colors of PWPCMs can be simultaneously
controlled by adjusting the flow rates in the microfluidic chips.
PWPCMs possess strictly monodispersed sizes with coefficients of variation
less than 1%. The free-standing PWPCMs have high thermal stability.
The deformation temperature of PWPCMs is as high as 210 °C. The
colored PWPCMs also exhibit a reversible thermochromic property between
the chiral nematic phase and the isotropic phase. The highly stable
and tunable PWPCMs provide new opportunities for a wide range of photonic
applications, including smart optical window, tunable microlasers,
responsive microsensors, and various photonic devices
Highly Biocompatible, Underwater Superhydrophilic and Multifunctional Biopolymer Membrane for Efficient Oil–Water Separation and Aqueous Pollutant Removal
Conventional
wastewater treatment systems generally require multiple
steps and complex procedures to remove aqueous pollutants and oil
contaminants from polluted water. Herein, we fabricate an underwater
superoleophobic membrane by cross-linking konjac glucomannan on pristine
fabrics, demonstrating that the concept of oil–water separation
and the principle of aqueous pollutant removal can be integrated.
Such biopolymer-modified fabric not only separates oil–water
mixtures with high efficiency (up to 99.9%), but also exhibits the
intriguing characteristic of removing water-soluble pollutants (including
polyaromatic dyes and heavy metal ions). As a proof of concept, the
synthetic wastewater purified with biopolymer membranes was used to
cultivate and irrigate pinto beans, causing no observable deleterious
effect on seed germination and growth. These results further confirm
the biocompatibility and effectiveness of biopolymer membranes, offering
an encouraging solution to challenges including wastewater treatment
and cleanup of oil spills
Hierarchical, Self-Healing and Superhydrophobic Zirconium Phosphate Hybrid Membrane Based on the Interfacial Crystal Growth of Lyotropic Two-Dimensional Nanoplatelets
We demonstrate a
facile route to in situ growth of lyotropic zirconium phosphate (ZrP)
nanoplates on textiles via an interfacial crystal growing process.
The as-prepared hybrid membrane shows a hierarchical architecture
of textile fibers (porous platform for fluid transport), ZrP nanoplatelets
(layered scaffolds for chemical barriers), and octadecylamine (organic
species for superhydrophobic functionalization). Interestingly, such
a hybrid membrane is able to separate the oily wastewater with a high
separation efficiency of 99.9%, even at in harsh environments. After
being chemically etched, the hybrid membrane is able to restore its
hydrophobicity autonomously and repeatedly, owing to the hierarchical
structure that enables facile loading of healing agent. We anticipate
that the concept of implanting superhydrophobic self-healing features
in anisotropic structure of lyotropic nanoparticles will open up new
opportunities for developing advanced multifunctional materials for
wastewater treatment, fuel purification, and oil spill mitigation