The morphology and size of Co-MOF-74 were effectively controlled by adjusting the water portion in DMF-H₂O mixed solvent system, and six different Co-MOF-74 samples were successfully obtained. The water content can alter the deprotonation rate of the organic ligand and then change the nucleation rate of crystal, thus regulate morphology and size of Co-MOF-74. The discrepancy of morphology and size has significant effect on texture structure of Co-MOF-74 but without changing their composition. The formation mechanism of crystal growth was proposed by studying the change of reaction solution pH value. These samples exhibit morphology and size dependent catalytic activity in toluene oxidation. The flower-like sample has the best catalytic performance with 12.1% toluene conversion and 63.8% benzaldehyde selectivity. Additionally, the influence of reaction parameters on the catalytic oxidation reaction was also examined. Rearserch on the structure-property relationship of catalyst would be useful for rationally synthesizing novel MOF in heterogeneous catalysis.

通过调节DMF-H _2中的水份可以有效地控制Co-MOF-74的形态和尺寸在混合溶剂系统中，成功获得了六个不同的Co-MOF-74样品。含水量可以改变有机配体的去质子化速率，然后改变晶体的成核速率，从而调节Co-MOF-74的形态和尺寸。形态和尺寸的差异对Co-MOF-74的纹理结构有重要影响，但不改变其组成。通过研究反应溶液pH值的变化，提出了晶体生长的形成机理。这些样品在甲苯氧化中表现出形态和尺寸依赖性催化活性。花状样品具有最佳的催化性能，甲苯转化率为12.1％，苯甲醛选择性为63.8％。另外，还研究了反应参数对催化氧化反应的影响。