Magnetic Au/Fe3O4/poly(styrene-sodium styrene sulphonate) composite microspheres (Au/Fe3O4/P(St-NaSS) CMs) were successfully prepared via a gamma-radiation method. Au and Fe3O4 were formed at the same time under irradiation and well dispersed on uniform P(St-NaSS) microspheres. The as-prepared CMs exhibit good catalytic properties and recyclable performances for the catalytic reduction of 4-nitrophenol (4-NP). The kinetic rate constants are 8.75 × 10−3 s−1 and 7.71 × 10−3 s−1 for two samples, respectively. The conversion rate of 4-NP can keep about 95% with catalysts after five cycles. They exhibit good magnetic behavior and have saturation magnetization value of about 9 emu g−1, which can be easily separated from the solution under external magnetic field. This strategy is efficient and facile, which can be extended to fabricate other CMs.

中文翻译：

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伽马辐射辅助制备催化用Au/Fe3O4/聚（苯乙烯-苯乙烯磺酸钠）磁性复合微球

通过伽马射线法成功制备了磁性 Au/Fe3O4/聚（苯乙烯-苯乙烯磺酸钠）复合微球（Au/Fe3O4/P(St-NaSS) CMs）。Au和Fe3O4在辐照下同时形成并很好地分散在均匀的P(St-NaSS)微球上。所制备的 CMs 在催化还原 4-硝基苯酚 (4-NP) 方面表现出良好的催化性能和可回收性能。两个样品的动力学速率常数分别为 8.75 × 10-3 s-1 和 7.71 × 10-3 s-1。4-NP 的转化率在 5 个循环后可以保持在催化剂的 95% 左右。它们表现出良好的磁性，饱和磁化强度约为 9 emu g-1，在外部磁场作用下可以很容易地从溶液中分离出来。该策略有效且简便，可以扩展到制造其他 CM。