SEARCH Articles Figures Tables 3D-Transition Metal Oxides 3d metal oxides 3d transition metals 3d transition-metal ions 3d-metal cations Metal Foams for 2D and 3D Battery Architectures Polymetallic complexes of 3d-metals Size of Transition 3d-Metal Ions Spinel-structured 3d-metal oxides Supramolecular 3D Architectures by Metal-directed Assembly of Synthetic Macrocycles