Enhancement of catalytic activity using two nano-structured Metal-Organic Frameworks (MOFs) synthesized via ultrasonic irradiation

Facile and environmentally friendly nano-scale synthesis of two new zinc and cadmium-organic frameworks (MOFs)1, {[Zn(NH2-BDC)(4-bpmbp)].2DMF}n (TMU-25) and {[Cd(NH2-BDC)(4-bpmbp)].2DMF}n (TMU-26), under ultrasonic irradiation at ambient temperature and atmospheric pressure has been explored. Ultrasonic irradiation is considered a green energy source because of shorter reaction times and higher yields in comparison to thermal energy sources.2 Controlling the growth of Nanometer-sized particles of metal–organic frameworks is captivating to explore, since their inimitable properties are controlled by the large number of surface molecules, which experience a completely different environment than those in a bulk crystal. The effect of different parameters like concentrations of initial reagents and reaction times on size and morphology of compounds was investigated. Furthermore, the catalytic behavior of TMU-25 nano-structures toward the Knoevenagel condensation reaction was compared with its bulk form. The Knoevenagel condensation is a typical test reaction for the evaluation of basic catalysts3, which is the most common used reaction for investigation of MOF containing basic functionalized structures due to its amenable reaction conditions

Keywords:

Metal-Organic Frameworks (MOF) , Ultrasonic irradiation , Knoevenagel condensation.