Fabrication and characterization of clay nanoscrolls and stable zerovalent iron using montmorillonite

Abstract Halloysite are naturally occurring nanotubes which due to unique structural properties have found tremendous applications. Here, we have described the fabrication of cylindrical-shaped clay nanoscrolls similar to natural halloysite nanotubes, first time from 2:1 type montmorillonite, with palladium and iron-loaded cellulose nanocrystals used as structural directing agents. Electrostatic interaction between negatively charged surface of clay sheets and γ-Fe2O3 resulted in the formation of clay nanoscrolls. Interestingly, change in the calcination environment of the process from normal atmospheric to nitrogen resulted in the formation of stable and ferromagnetic zero-valent iron (ZVI) on the clay support instead of the scrolls. The prepared clay nanoscrolls can be used in different application as an alternative of halloysite. Here, we checked the hydrogen adsorption capacity of nanoscrolls, which showed the comparative results reported in the literature for halloysite. Similarly, the clay nanoscrolls showed good H2O2 reduction ability in the alkaline medium. Permanent magnetic nature of ZVI improves induction heating, and thus can be applied in the biomedical field. Thus, a sustainable approach for fabrication of hallyosite nanotube alternate clay nanoscrolls and stable ZVI has been described here.