TY - JOUR

T1 - Alignment of Amorphous Iron Oxide Clusters: A Non-Classical Mechanism for Magnetite Formation.

AU - Sun, S

AU - Gebauer, D

AU - Cölfen, H

N1 - Funding information: S.T.S. gratefully acknowledges the financial support from the Alexander von Humboldt Foundation and the National Science Foundation of China (NSFC; No. 21604024). D.G. is a Research Fellow of the Zukunftskolleg of the University of Konstanz, and supported by the Fonds der Chemischen Industrie. This work was also supported by the facilities in the Nanostructure Laboratory of the University of Konstanz. We thank Marina Krumova for TEM, Baohu Wu for SAXS, Martin Stärk for magnetization, Xuezhi Duan of East China University of Science and Technology for XPS analysis, and Ulrich Nowak for valuable discussions. Rose Rosenberg and Cornelia Schneider are acknowledged for performing the AUC experiments and the 2DSA analysis, respectively. We also thank the Jülich Supercomputing Centre for allocating computing time for the evaluation of the AUC data using UltraScan (Grant HKN000). S.T.S. gratefully acknowledges the financial support from the Alexander von Humboldt Foundation and the National Science Foundation of China (NSFC; No. 21604024). D.G. is a Research Fellow of the Zukunftskolleg of the University of Konstanz, and supported by the Fonds der Chemischen Industrie. This work was also supported by the facilities in the Nanostructure Laboratory of the University of Konstanz. We thank Marina Krumova for TEM, Baohu Wu for SAXS, Martin St?rk for magnetization, Xuezhi Duan of East China University of Science and Technology for XPS analysis, and Ulrich Nowak for valuable discussions. Rose Rosenberg and Cornelia Schneider are acknowledged for performing the AUC experiments and the 2DSA analysis, respectively. We also thank the J?lich Supercomputing Centre for allocating computing time for the evaluation of the AUC data using UltraScan (Grant HKN000).

PY - 2017/3/22

Y1 - 2017/3/22

N2 - Despite numerous studies on the nucleation and crystallization of iron (oxyhydr)oxides, the roles of species developing during the early stages, especially primary clusters and intermediate amorphous particles, are still poorly understood. Herein, both ligand-free and ligand-protected amorphous iron oxide (AIO) clusters (<2 nm) were synthesized as precursors for magnetite formation. Thermal annealing can crystallize the clusters into magnetite particles, and AIO bulk phases with domains of pre-aligned clusters are found to be direct precursors to crystals, suggesting a non-classical aggregation-based pathway that differs from the reported oriented attachment or particle accretion mechanisms.

AB - Despite numerous studies on the nucleation and crystallization of iron (oxyhydr)oxides, the roles of species developing during the early stages, especially primary clusters and intermediate amorphous particles, are still poorly understood. Herein, both ligand-free and ligand-protected amorphous iron oxide (AIO) clusters (<2 nm) were synthesized as precursors for magnetite formation. Thermal annealing can crystallize the clusters into magnetite particles, and AIO bulk phases with domains of pre-aligned clusters are found to be direct precursors to crystals, suggesting a non-classical aggregation-based pathway that differs from the reported oriented attachment or particle accretion mechanisms.

KW - aggregation

KW - amorphous iron oxide

KW - clusters

KW - crystal growth

KW - self-assembly

UR - http://www.scopus.com/inward/record.url?scp=85014361966&partnerID=8YFLogxK

U2 - 10.1002/anie.201610275

DO - 10.1002/anie.201610275

M3 - Article

C2 - 28252244

VL - 56

SP - 4042

EP - 4046

JO - Angewandte Chemie - International Edition

JF - Angewandte Chemie - International Edition

SN - 1433-7851

IS - 14

ER -