Ultrasonic-assisted synthesis of nano-sized metal-organic framework; a simple method to explore selective and fast Congo Red adsorption

A novel mixed linker Metal-organic Framework, Co(NH₂IsoBDC)(bpfn)].DMF (TMU-69), with amide and amino functionalized spacers (bpfn = N,N'-(naphthalene-1,5-diyl)diisonicotinamide, NH₂IsoBDCH₂ = 5-Aminoisophthalic acid) was synthesized through both solvothermal and ultrasonic approaches. Applying sonochemical irradiation led to ultrafast formation of Flower-shaped nanoplates of TMU-69 within 15 min with high yield while, solvothermal method takes 3 days to form the framework. Control of size and morphology was also enhanced through applying ultrasonic irradiations. The implication of applied time and concentration of reagents on size and morphology of nano-structured TMU-69 have been optimized. Applying higher concentration of initial material with optimized 60-minute irradiation forms uniform smaller sized nanoplates of TMU-69. Also, the efficiency of TMU-69 bulk and nanoplates toward removal of pollutant dyes from water was investigated. The selective adsorption of Congo Red was observed among other dyes. Also, drastic enhancement in removal kinetic of Congo Red through using ultrasonic assisted nanoplates of TMU-69 was obtained.