Preparation and Characteristics of Novel Fibers Based on Cellulose Acetate and Soy Lecithin for Attracting and Binding POPs

Soy lecithin (SL)-modified cellulose acetate (L-CA) fibers for use as a novel biomimic material were prepared by a dry-jet wet spinning process from a solution of the polymer in dioxin. Characteristics of the L-CA fibers, such as structural properties, water absorbance, electrical conductivity and accumulation of trace persistent organic pollutants (POPs), were examined. Cross-sectional scanning electron microscopy (SEM) of L-CA unveiled a finger-like structure, along with a thin dense surface layer like that of CA. On the basis of X-ray photoelectron spectroscopic (XPS) observations, it was concluded that the enhancement of binding energy was optimum with 10% SL in the fiber, whereas superfluous SL led to self-assembly between the SL molecules, which weakened the binding between the SL and CA. Also, the L-CA fibers showed good water absorbance and a low charge conductivity in comparison to that of the non-modified CA fibers. Examination of the ability to accumulate POPs from water showed that L-CA is a effective candidate for the removal of micropollutants from aqueous solution.

Two-dimensional Ti_(3)C_(2)T_(X)-nanosheets/Cu_(2)O composite as a high-performance photocatalyst for decomposition of tetracycline

Construction of photocatalysts with a Schottky heterojunction could realize highly efficient and stable degradation of organic pollutes in the wastewater.In this work,a precipitation method was used to prepare Ti_(3)C_(2)T_(X)-nanosheets/Cu_(2)O composite photocatalysts with the Schottky heterojunction for the decomposition of tetracycline(TC)antibiotics under visible light.As-prepared photocatalysts were characterized by various techniques such as X-ray diffraction analysis(XRD),High resolution transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS).When the best Ti_(3)C_(2)T_(X)-nanosheets/Cu_(2)O composite was applied for the degradation of TC under visible light,the degradation efficiency reached up to 97.6%only in 50 min.It is considered that superoxide radical(O_(2)^(→))and hole(h^(+))were the main reactive species for the TC degradation,and in the Schottky heterojunction,e^(-)-h^(+)pairs in the catalyst could be transferred and separated effectively,resulting in obviously enhanced photocatalytic efficiency and stability.

Green preparation of self-supporting platinum nanoflower catalyst and its electrocatalytic oxidation performance of methanol

The three-dimensional(3D)self-supporting Pt nanoflower catalyst was prepared by using Pt organic compounds as precursors in a low-temperature molten salt system.The obtained Pt nanoflower nanoparticle can reach 400-500 nm with a face-centered cubic structure,which has the structural characteristics of a loose framework and more exposed active sites.The surfactant-free Pt nanoflower was directly used as methanol electrooxidation reaction(MOR)electrocatalysts without any pretreatment and activated carbon support.The results of electrochemical catalytic oxidation of methanol showed that the Pt nanoflower catalyst exhibit more enhanced electrocatalytic oxidation performance toward methanol compared with the commercial platinum black catalyst.The green and effective method can be developed and expected to enable mass production of fuel cell catalysts.