Nanoporous oxides in thin film format have been receiving much attention in recent years, especially because of their potential for next generation device applications. However, the preparation of non-siliceous (mixed-metal) oxides that are structurally and compositionally well-defined is challenging. The primary reason is that both the nucleation and growth of the crystalline phase are usually difficult to control.

Here we describe the block-copolymer-templating synthesis (using an evaporation-induced self-assembly process) of a series of high quality large-pore mesoporous oxides with spinel and perovskite structures, including metal ferrites and mixed-valence manganese oxides, and their characterization by various imaging, diffraction, and spectroscopic methods. Besides, we demonstrate that the general idea of combining nanomagnetism and electrochemical energy storage concepts can be applied to block-copolymer-templated mixed-metal oxide thin films. Using such high-surface-area materials as the working electrode in lithium-ion battery cells or supercapacitors and carefully controlling the charge/discharge potential allows tuning (virtually fully reversible) the magnetism at room temperature without compromising the lattice and/or pore structure.[1-4] The results are exciting and clearly show that both techniques hold potential for application in the fields of micromagnetic actuation and spintronics to name a few.

[1] C. Reitz, P. M. Leufke, R. Schneider, H. Hahn and T. Brezesinski, Chem. Mater. 2014, 26, 5745.

[2] C. Reitz, C. Suchomski, D. Wang, H. Hahn and T. Brezesinski, J. Mater. Chem. C 2016, 4, 8889.

[3] C. Reitz, D. Wang, D. Stoeckel, A. Beck, T. Leichtweiss, H. Hahn and T. Brezesinski, ACS Appl. Mater. Interfaces 2017, 9, 22799.

[4] L. A. Dubraja, C. Reitz, L. Velasco, R. Witte, R. Kruk, H. Hahn and T. Brezesinski, ACS Appl. Nano Mater. 2018, 1, 65.