Synthesis and characterization of MXene/metal-organic frameworks(MXOF) nanocomposite for dye removal application

Organic dyes are the most important organic pollutants released from wastewater bydifferent industries such as textile, printing, paper, and cosmetic industries[۱].Their nonbiodegradablenature, toxicity, and potential adverse effects on human health have made them abig serious environmental concern[۲]. Among various wastewater treatment approaches,adsorption-based processes, due to their simplicity, high efficiency, and reliability, have gainedimmense attention. Recently, a new class of two-dimensional transition metal carbides, nitrides,and carbonitrides, named MXenes were discovered by researchers at Drexel University. MXeneNSs have a general formula of Mn+۱XnTx(n=۱–۳)[۱]. On the other hand, metal-organicframeworks (MOFs), as relatively new emerging nanoporous crystalline materials, possess alarge specific surface area, tunable pore size, and high porosity. Zeolitic imidazolateframeworks (ZIFs) are a class of MOFs. ZIF-۸ is a typical representative of ZIF materials,which is a kind of albite zeolite with a nanoporous structure [۳].In this study, a zinc-basedmetal-organic framework (MOF) decorated MXene (MXOF) nanocomposite was successfullysynthesized [۴] and utilized for the adsorptive removal of organic dyes from wastewater. AcidRed ۸۸ (AR۸۸) was selected as the model organic contaminant owing to its stable molecularstructure and various application in the textile industry. Investigating the morphology of MXOFby field-emission scanning electron microscopy (FESEM)revealed the formation of crystallinespherical particles of ZIF-۸ with an average particle size of ~۴۵۰ nm over MXene NSs. Fouriertransform infrared spectroscopy (FTIR)and X-ray diffraction (XRD)were also carried out tostudy, the structural and crystalline characteristics of MXOF. According to the results of theBrunner-Emmet-Teller (BET) analysis, the specific surface area and average pore size of theMXOF nanocomposite were found to be ۱۲۳۲.۵ m۲/g and ۰.۵۵۶۴ cm۳/g, respectively. Then,thedye absorption was studiedshowing a high adsorption capacity of ۱۹۱.۴۴ mg/g. Theabsorption isotherm and kinetics followed Temkepinisotherm model and pseudo-second-orderkinetic model, respectively.

کلیدواژه ها:

Adsorption ، Dye removal ، Metal-organic frameworks ، MXene nanosheets