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Despite the great potential of graphene as a nanofiller, its inhomogeneous dispersion in polymers remains a key challenge for the effective reinforcement of polymer. Herein, we exfoliated worm graphite into graphene by in situ liquidphase exfoliation, and the graphene was coated on the surface of polypropylene (PP) pellets by stirring. Further, we examined several treatment conditions and graphene contents. When graphene was centrifuged at 1000 rpm and the extrusion temperature of the composite was 230 C, the composite achieved optimal overall performance with the addition of only 0.2 wt% graphene. Compared to those of pure PP, the yield strength, bending modulus, and impact strength of the composites increased by 8.71%, 18.32%, and 45.75%, respectively. The thermal conductivity is increased by 29.5%. X-ray diffraction (XRD) and differential scanning calorimetry (DSC) showed that the PP sample exhibited a significant heterogeneous nucleation effect due to graphene addition, improving the crystallization temperature and crystallinity of the composites. Contact angle measurement and scanning electron microscopy (SEM) revealed that the surface energy of graphene and PP are close to each other, and the graphene was well-dispersed in the PP matrix. Thus, this technique can optimize the processing properties and interface structure of graphenepolymer nanocomposites.

Photocatalytic degradation of organic pollution is a vital path to deal with environmental problems. Here, a direct Zscheme 2D/2D heterojunction of a Fe 3 O 4 /Bi 2 WO 6 photocatalyst is fabricated for the degradation of ciprofloxacin by a self-assembly strategy. Furthermore, to characterize the morphology of the obtained composite photocatalysts, various kinds of characterization methods were employed like XRD, XPS, SEM, and TEM. It is indicated that the flower-like photocatalyst is composed of nanosheets. Comparable photocatalysts were prepared by controlling the hydrothermal temperature and the iron content. In the photocatalytic degradation of ciprofloxacin (CIP) in water, under visible light irradiation, FB-180 (synthesized at 180 °C with 4% iron content) presents approximately 99.7% degradation efficiency in only 15 min. Meanwhile, during photocatalytic degradation reactions, the Fe 3 O 4 /Bi 2 WO 6 heterojunction also displayed excellent stability, which still kept above 90% degradation efficiency after five consecutive cycles. UV−Vis DRS and M-S analyses showed that the Fe 3 O 4 /Bi 2 WO 6 catalyst has a strong visible light absorption capacity and the transfer pathway of photo-induced charge carriers. PL, EIS, and TPR showed that Fe 3 O 4 /Bi 2 WO 6 has an efficient separation and transfer rate of the photo-generated carriers. ESR analysis proved that the superoxide radical ( • O 2 − ) and hydroxyl radical ( • OH) play a major role in the Fe 3 O 4 /Bi 2 WO 6 photocatalytic system. This special 2D/2D heterojunction we proposed may have huge potential for marine pollution treatment by photocatalysis degradation with dramatically boosted activities.

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