Morphology-dependent nanocatalysis on metal oxides

The design and fabrication of solid nanomaterials are the key issues in heterogeneous catalysis to achieve desired performance. Traditionally, the main theme is to reduce the size of the catalyst particles as small as possible for maximizing the number of active sites. In recent years, the rapid advancement in materials science has enabled us to fabricate catalyst particles with tunable morphology. Consequently, both size modulation and morphology control of the catalyst particles can be achieved independently or synergistically to optimize their catalytic properties. In particular, morphology control of solid catalyst particles at the nanometer level can selectively expose the reactive crystal facets, and thus drastically promote their catalytic performance. In this review, we summarize our recent work on the morphology impact of Co₃O₄, CeO₂ and Fe₂O₃ nanomaterials in catalytic reactions, together with related literature on morphology-dependent nanocatalysis of metal oxides, to demonstrate the importance of tuning the shape of oxide-nanocatalysts for prompting their activity, selectivity and stability, which is a rapidly growing topic in heterogeneous catalysis. The fundamental understanding of the active sites in morphology-tunable oxides that are enclosed by reactive crystal facets is expected to direct the development of highly efficient nanocatalysts.