Forced hydrolyses in the precipitation systems (a) Fe(NO 3 ) 3 /Fe 2 (SO 4 ) 3 and FeCl 3 /Fe 2 (SO 4 ) 3 and (b) FeCl 3 /N-guanylurea sulphate were investigated using 57 Fe Mössbauer and FT-IR spectroscopies and scanning electron microscopy (FE SEM). Forced hydrolyses of Fe(NO 3 ) 3 /Fe 2 (SO 4 ) 3 solutions at 90 °C yielded superparamagnetic goethite nanorods, whereas in the case of FeCl 3 /Fe 2 (SO 4 ) 3 solutions the clusters of akaganéite nanoneedles were formed. With a prolonged heating time at 90 °C the conversion of these akaganéite nanoneedles into goethite nanorods was observed. Forced hydrolysis in the system FeCl 3 /N-guanylurea sulphate at 160 °C generated only hematite and goethite phases and their fractions depended on the concentration of FeCl 3 and the amount of N-guanylurea sulphate in the solution. Different shapes of iron(III) oxyhydroxides and hematite in dependence on the experimental conditions were monitored with FE SEM. Specifically adsorbed sulphates on these particles, as shown by FT-IR spectroscopy, served as directing agents in the particle/crystal growth.

中文翻译：

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在混合阴离子和促进剂存在下水解 Fe(III)

使用 57 Fe 研究了沉淀系统 (a) Fe(NO 3 ) 3 /Fe 2 (SO 4 ) 3 和 FeCl 3 /Fe 2 (SO 4 ) 3 和 (b) FeCl 3 /N-鸟苷脲硫酸盐中的强制水解Mössbauer 和 FT-IR 光谱和扫描电子显微镜 (FE SEM)。Fe(NO 3 ) 3 /Fe 2 (SO 4 ) 3 溶液在 90 °C 下强制水解产生超顺磁性针铁矿纳米棒，而在 FeCl 3 /Fe 2 (SO 4 ) 3 溶液的情况下，形成了赤铁矿纳米针簇. 随着在 90 °C 下延长加热时间，观察到这些赤铁矿纳米针转化为针铁矿纳米棒。在 160 °C 的 FeCl 3 /N-鸟苷脲硫酸盐系统中强制水解仅生成赤铁矿和针铁矿相，它们的分数取决于 FeCl 3 的浓度和溶液中 N-鸟苷脲硫酸盐的量。使用 FE SEM 监测依赖于实验条件的不同形状的铁 (III) 羟基氧化物和赤铁矿。如 FT-IR 光谱所示，这些颗粒上特别吸附的硫酸盐充当颗粒/晶体生长的导向剂。