Shape-Controlled Synthesis of Manganese Oxide Octahedral Molecular Sieve Three-Dimensional Nanostructures Direct architecture plex nanostructures is desirable and still remains a challenge in areas of materials science. Due to their size- and shape-dependent electronic and optical properties, much effort has been made to control morphologies of transition metal oxide nanoparticles and anize them plicated 3D structures using templates. In particular, manganese oxides have attracted much attention because they have extensive applications in many chemical processes due to their porous structures, acidity, ion-exchange, separation, catalysis, and energy storage in secondary batteries. anic templates, such as trimethylamine (TMA), manganese oxides have been anized into macroscopic rings and helices via sol gel processes. However, the methods mentioned above all need further purification, so impurities will be introduced. Subsequent procedures are needed to obtain pure products. Thus, facile anic template-free methods are highly desired for synthesis of manganese oxide nanoparticles plex 3D structures. Manganese oxide octahedral molecular sieves (OMS) are a class of microporous transition metallic oxides with various kinds of tunnel structures that can be synthesized via controlling synthetic conditions, such as temperature, concentration, pH, and cations. Manganese oxide molecular s