Contact-electro-catalysis for the degradation of organic pollutants using pristine dielectric powders

Mechanochemistry has been studied for some time, but research on the reactivity of charges exchanged by contact-electrification (CE) during mechanical stimulation remains scarce. Here, we demonstrate that electrons transferred during the CE between pristine dielectric powders and water can be utilized to directly catalyze reactions without the use of conventional catalysts. Specifically, frequent CE at Fluorinated Ethylene Propylene (FEP) - water interface induces electron-exchanges, thus forming reactive oxygen species for the degradation of an aqueous methyl orange solution. Contact-electro-catalysis, by conjunction of CE, mechanochemistry and catalysis, has been proposed as a general mechanism, which has been demonstrated to be effective for various dielectric materials, such as Teflon, Nylon-6,6 and rubber. This original catalytic principle not only expands the range of catalytic materials, but also enables us to envisage catalytic processes through mechano-induced contact-electrification.

Tribological, Mechanical and Thermal Properties of Fluorinated Ethylene Propylene Filled with Al-Cu-Cr Quasicrystals, Polytetrafluoroethylene, Synthetic Graphite and Carbon Black

Antifriction hybrid fluorinated ethylene propylene-based composites filled with quasicrystalline Al73Cu11Cr16 powder, polytetrafluoroethylene, synthetic graphite and carbon black were elaborated and investigated. Composite samples were formed by high-energy ball milling of initial powders mixture with subsequent consolidation by injection molding. Thermal, mechanical, and tribological properties of the obtained composites were studied. It was found that composite containing 5 wt.% of Al73Cu11Cr16 quasicrystals and 2 wt.% of nanosized polytetrafluoroethylene has 50 times better wear resistance and a 1.5 times lower coefficient of dry friction comparing with unfilled fluorinated ethylene propylene. Addition of 15 wt.% of synthetic graphite to the above mentioned composition allows to achieve an increase in thermal conductivity in 2.5 times comparing with unfilled fluorinated ethylene propylene, at that this composite kept excellent tribological properties.

EDTA interfacial chelation Ca2+ incorporates superhydrophobic coating for scaling inhibition of CaCO3 in petroleum industry

In this paper, the superhydrophobic poly(vinylidene fluoride)/fluorinated ethylene propylene/SiO2/CNTs-EDTA (PFSC-EDTA) composite coating was successfully fabricated and applied for anti-scaling performance. The deposition of CaCO3 on the surface of the superhydrophobic PFSC-EDTA composite coating reached 0.0444 mg/cm2 for 192-h immersion into the supersaturated CaCO3 solution, which was only 11.4% that of the superhydrophobic PFSC composite coating. At the interface between the CaCO3 solution and the PFSC-EDTA coating, the Ca2+ could be firstly chelated by EDTA that was benefit for improving the anti-scaling performance of the superhydrophobic PFSC-EDTA composite coating. In another hand, the addition of EDTA to the CNTs played an important role in fabricating the SiO2-centric and CNTs-EDTA-surrounded multilevel micro–nanostructure in the superhydrophobic PFSC-EDTA composite coating, in favor of maintaining the air film under the water and the stability of the superhydrophobic surface. The research supplies a new way of improving anti-scaling performance of superhydrophobic coating by incorporating the organic chelating agent at the interface and changing the traditional way of scale prevention.

A Multi-Functional Microfluidic Device Compatible with Widefield and Light Sheet Imaging

We present a microfluidic device compatible with high resolution light sheet and super-resolution microscopy. Our device is a 150 μm thick chamber with a transparent fluorinated ethylene propylene (FEP) cover...

Thin fluorinated polymer film microcavity arrays for 3D cell culture and label-free automated feature extraction

A microengineered fluorinated ethylene-propylene based cell culture system was developed for automated, label-free feature extraction from 3D stem cell cultures.