Heterogeneous catalytic reactions involved in the vapor-liquid-solid (VLS) or solution-liquid-solid(SLS) growth of 1-D nanostructures have been intensively investigated in recent years. But how to control thehomogeneous catalytic route and apply it to design new structures of materials has rarely been discussed. In thiswork, a homogeneous catalyst was successfully controlled via changing the catalyst feed way, and three novel
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-MnO
2hierarchical structures, namely, urchin-like structures, sphere networks, and nanowire networks, were selectivelysynthesized at room temperature.
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-MnO
2 nanorods were also prepared via this method at higher temperatures.The present work indicates that the homogeneous catalytic route not only can produce one certain structure ofinorganic materials but also can be rationally controlled and therefore used to grow more new structures. On theother hand, this homogeneous catalytic method is a solution-based self-assembly route, providing a simple, mild,and template-free way to the fabrication of hierarchical structures.