Department of Chemical Engineering, Qufu Normal University, Shandong, 273165, China.
Nanoscale Res Lett. 2013 Jan 2;8(1):2. doi: 10.1186/1556-276X-8-2.
Hollow or porous hematite (α-Fe2O3) nanoarchitectures have emerged as promising crystals in the advanced materials research. In this contribution, hierarchical mesoporous α-Fe2O3 nanoarchitectures with a pod-like shape were synthesized via a room-temperature coprecipitation of FeCl3 and NaOH solutions, followed by a mild hydrothermal treatment (120°C to 210°C, 12.0 h). A formation mechanism based on the hydrothermal evolution was proposed. β-FeOOH fibrils were assembled by the reaction-limited aggregation first, subsequent and in situ conversion led to compact pod-like α-Fe2O3 nanoarchitectures, and finally high-temperature, long-time hydrothermal treatment caused loose pod-like α-Fe2O3 nanoarchitectures via the Ostwald ripening. The as-synthesized α-Fe2O3 nanoarchitectures exhibit good absorbance within visible regions and also exhibit an improved performance for Li-ion storage with good rate performance, which can be attributed to the porous nature of Fe2O3 nanoarchitectures. This provides a facile, environmentally benign, and low-cost synthesis strategy for α-Fe2O3 crystal growth, indicating the as-prepared α-Fe2O3 nanoarchitectures as potential advanced functional materials for energy storage, gas sensors, photoelectrochemical water splitting, and water treatment.
具有中空或多孔结构的赤铁矿 (α-Fe2O3) 纳米结构已成为先进材料研究中极具前景的晶体。在本研究中，通过室温下的 FeCl3 和 NaOH 溶液共沉淀，然后进行温和的水热处理 (120°C 至 210°C，12.0 小时)，合成了具有豆荚状形貌的分级介孔 α-Fe2O3 纳米结构。提出了一种基于水热演变的形成机制。β-FeOOH 纤维首先通过反应限制聚集组装，随后的原位转化导致致密的豆荚状 α-Fe2O3 纳米结构，最后在高温、长时间水热处理下，通过奥斯特瓦尔德熟化导致疏松的豆荚状 α-Fe2O3 纳米结构。所合成的 α-Fe2O3 纳米结构在可见光区域内具有良好的吸光度，并且由于 Fe2O3 纳米结构的多孔性质，其在锂离子存储方面表现出良好的性能，具有良好的倍率性能。这为 α-Fe2O3 晶体生长提供了一种简便、环保且低成本的合成策略，表明所制备的 α-Fe2O3 纳米结构作为储能、气体传感器、光电化学水分解和水处理等领域的潜在先进功能材料具有广阔的应用前景。
