We demonstrate the use of a supernormal

valence transition-metal (Ce(IV) and Cu(III))-mediated redox system for the

surface grafting on the halloysite nanotubes (HNTs).

Following this way, commonly-used vinyl monomers were grafted on HNTs in one

step under mild

condition. The grafting was evidenced using FTIR,

X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis (TGA).

The micromorphology was carefully characterized by transmission electron

microscope (TEM). The results indicate that the surface grafting reaction was

successfully processed in all cases, in which the Ce(IV) shows a much higher

initiation activity than that of Cu(III). Then a uniform hydrogel was

constructed by mixing polycation-grafted HNTs (HNTs-P(Et-P)) with

polyanion-grafted HNTs (HNTs-P(AA-Na)), which show desirable antibacterial

activity.