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Qin, Shuang

Publications and source records attributed to Qin, Shuang.

Carbon material supported hollow metal oxide nanoparticles, methods and applications

A method for preparing a material composition comprising a hollow transition metal oxide nanoparticle supported upon a carbon material support includes a solution impregnation process step, followed by a thermal reduction process step and finally a thermal oxidation process step. The material composition, an electrode and an electrical component such as but not limited to a battery are all predicated at least in-part upon the material composition prepared in accord with the foregoing method. The foregoing material composition, electrode, battery and method may ultimately provide a LIB with enhanced performance.

Yu, Yingchao↗

Influence of Clay size on corrosion protection by Clay nanocomposite thin films

In this work, the influence of clay platelet size on the corrosion barrier performance of highly-aligned polymer clay nanocomposite (PCN) thin films was examined. Layer-by-layer (LbL) deposition of alternating branched polyethylenimine (PEI) and either laponite (LAP), montromorillonite (MMT) or vermiculite (VMT) clay platelets were assembled on mild steel plates to obtain 20 bilayer (BL) films and cross-linked using glutaraldehyde after deposition. The clay platelets were chosen based on their aspect ratio, approximately 30:1, 400:1, and 2000:1, respectively. Electrochemical impedance spectroscopy of the coated steel plates during immersion showed corrosion rates and coating permeability followed LAP > MMT > VMT for up to 7 days of exposure in 0.6 M NaCl. The PEI/VMT films, ~250 nm thick, slowed corrosion by a factor of >1000 compared to bare steel. The results support the premise that high aspect ratio clay platelets can improve the corrosion barrier efficacy of LbL PCN films by decreasing film permeability and provide exceptional protection to steel in saline environments compared to other thin multilayer coatings and pretreatments.

36 MATERIALS SCIENCE↗