Youyi Sun

Facile synthesis of snowflake-like magnetic Fe–Ni alloy with high magnetic properties

Abstract Snowflake-like Fe–Ni alloy has been synthesised via a facile hydrothermal approach without any soft and hard template. The structure of the snowflake-like Fe–Ni alloy was characterised by means of scanning electron microscopy (SEM), X-ray diffraction and energy dispersive X-ray spectroscopy. The dendrite trunk lengths of the snowflake-like Fe–Ni alloy were about 2·5–7·0 μm, and those of the branch trunk ranged from 250·0 to 650·0 nm. Furthermore, it was found that the formation and morphology of Fe–Ni alloy strongly depended on the reaction time. Moreover, the magnetic and electrical properties of Fe–Ni alloy with various morphologies were compared. Moreover, the result showed that the snowflake-like Fe–Ni alloy indicated enhancement of their ferromagnetic and electrical properties, which was attributed to their anisotropic shape.

Simple synthesis of zwitterionic diblock copolymers for the application on metal nanoparticles preparation

AB diblock copolymers of poly(2-(dimethylamino)ethyl metharylate-block-potassiurn acrylate) were prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. The structure of the block polymer was determined by the nuclear magnetic resonance (NMR) spectroscopy and the gel permeation chromatography. Moreover, it has also been shown that the diblock copolymers exhibit aggregate as function of the pH according to the result of 1H-NMR spectroscopy, FT-IR absorption spectra, UV-vis transmittance spectroscopy, transmission electron microscopy and ultrasonic particle size analyzer. The result was attributed that such AB diblock copolymers were tailored to undergo pH-induced self-assembly. Furthermore, the aggregate can be as template of metal nanoparticles preparation, and the sizes of the aggregate, in turn, strongly control nanoparticle sizes.