writer：Jiang Gong, Jie Liu, Zhiwei Jiang, Xin Wen, Ewa Mijowska, Tao Tang*, Xuecheng Chen*
keywords：Porous cup-stacked CNT; Adsorption; Methylene blue; KOH activation; Recyclability; Adsorption mechanism; Polypropylene
source：期刊
specific source：Journal of Colloid and Interface Science 445 (2015) 195-204
Issue time：2015年
Novel porous cup-stacked carbon nanotube (P-CSCNT) with special stacked morphology consisting of many truncated conical graphene layers was synthesized by KOH activating CSCNT from polypropylene. The morphology, microstructure, textural property, phase structure, surface element composition and thermal stability of P-CSCNT were investigated by field-emission scanning electron microscope, transmission electron microscope (TEM), high-resolution TEM, N2 sorption, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and thermal gravimetric analysis. A part of oblique graphitic layers were etched by KOH, and many holes with a diameter of several to a doze of nanometers connecting inner tube with outside were formed, which endowed P-CSCNT with high specific surface area (558.7 m2/g), large pore volume (1.993 cm3/g) and abundant surface functional groups. Subsequently, P-CSCNT was used for adsorption of methylene blue (MB) from wastewater. Langmuir model closely fitted the adsorption results, and the maximum adsorption capacity of P-CSCNT was as high as 319.1 mg/g. This was ascribed to multiple adsorption mechanisms including pore filling, hydrogen bonding, π–π and electrostatic interactions. Pseudo second-order kinetic model was more valid to describe the adsorption behavior. Besides, P-CSCNT showed good recyclablity and reusability. These results demonstrated that P-CSCNT had potential application in wastewater treatment.