Simultaneous Delamination and Rutile Formation on the Surface of Ti <sub>3</sub> C <sub>2</sub> T <sub> <i>x</i> </sub> MXene for Copper Adsorption
Elumalai Satheeshkumar, Masahiro Yoshimura, Makoto Ogawa
Abstract
Abstract In this work, we studied the formation of the rutile phase of titanium dioxide (TiO 2 ) on delaminated MXene ( d ‐Ti 3 C 2 T x ) flakes by the reaction of Ti 3 C 2 T x with amino acids in water. Three types of amino acids with varied side‐chain polarity were used to delaminate Ti 3 C 2 T x . d ‐Ti 3 C 2 T x flakes formed stable colloidal solutions due to the negative surface charges of chemisorbed amino acids on the d ‐Ti 3 C 2 T x . Rutile formed on d ‐Ti 3 C 2 T x at room temperature upon the intercalation of aromatic amino acids and subsequent sonication of the solution, while flakes intercalated with aliphatic amino acids did not oxidize. X‐Ray diffraction (XRD), transmission electron microscopy (TEM) and Raman spectroscopy revealed the nanosize rutile formation on the surface of Ti 3 C 2 T x flakes. The XPS results indicated the surface functionalization of histidine on d ‐Ti 3 C 2 T x flakes. As‐synthesized histidine functionalized rutile TiO 2 @ d ‐Ti 3 C 2 T x hybrid was used for adsorption of Cu 2+ ions from aqueous solution with a maximum uptake of 95 mg g −1 .