Two-dimensional (2D) Ti₃C₂T_x MXene nanosheets with superior adsorption behavior for phosphate and nitrate ions from the aqueous environment

With the advancement of modern industries and metropolitan areas, negative environmental impacts such as eutrophication have become serious issues obstructing the usage of water sources in many countries. In this study, two-dimensional (2D) MXene materials were employed for the adsorptive removal of phosphate and nitrate ions from waters. The adsorption parameters of the sorption system including reaction time, solution pH, background ions, and reusability, were evaluated in batch experiments. Material characterization techniques, including X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy, thermal gravimetric analysis, Brunauer–Emmett–Teller analysis, and high-resolution transmission electron microscopy were performed. The mechanism of removing phosphate and nitrate was clearly described by various kinds of interactions such as electrostatic interactions, and the complexation was significant to elucidate the adsorption mechanism. The adsorption data for phosphate and nitrate update was determined using different isotherms and kinetic models. Reusability and field studies on the MXenes were also conducted. The above findings demonstrate that 2D MXenes could act as promising adsorbents for the elimination of toxic ions from water/wastewater.