Co3O4 nanocubes that were exclusively terminated with{100}facets of edge size 10 nm were solvothermal y fabricated in a mixed solution of ethanol and triethylamine. Analyses of the structural evolution of the intermediates at different intervals during the synthesis, together with an examination of the influences of the cobalt precursor and solvent on the product structure, showed that the formation of Co3O4 nanocubes fol owed a dissolution-recrystal ization mechanism. After calcination at 200 ° C, the as-synthesized Co3O4 material retained a cubic morphology with the same edge size, but calcination at 400 ° C resulted in the formation of spherical Co3O4 particles of diameter about 13 nm. The Co3O4 nanocubes exhibited inferior activity in room-temperature CO oxidation compared with Co3O4 nanoparticles ({111}facets), primarily as a result of the exposure of the less-reactive {100} facets, demonstrating the morphology effect of Co3O4 nanomaterials.%在乙醇和三乙胺的混合溶液中，采用溶剂热法制备了尺寸为10 nm的Co3O4立方体。考察了钴盐前驱体和溶解氧对Co3O4纳米立方体结构的影响规律，通过对合成过程中不同阶段产物的结构分析和表征，提出了Co3O4纳米立方体的形成机制是溶解再结晶的过程。将所制备的Co3O4纳米立方体在200°C焙烧处理后，尺寸和形貌均可保持稳定，但400°C焙烧后，变为球形纳米粒子。这种主要暴露{100}晶面的Co3O4纳米立方体催化CO氧化反应的活性低于纳米粒子({111}晶面)，验证了四氧化三钴纳米材料在CO氧化反应中的晶面效应。
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