Absorbate-induced ordering and bilayer formation in Propanol-Graphite Oxide intercalates: a neutron diffraction study in real-time

Abstract

The subnanometer size of the interlayer space of graphite oxide (GO) offers exciting opportunities in the design of materials for separation technologies, hydrogen storage, gas capture, and 2D confinement studies [1-4]. Pillaring GO by intercalation of organic and inorganic molecules is an extended method to synthesize porous materials with a tunable pore size [2]. In the present work, we study the kinetics of intercalation and deintercalation of 1-Pr in a Brodie-synthesized GO by making recourse of the unique capabilities of neutron diffraction. A simple para-crystalline model allows us to obtain detailed structural information from the width and position of the first diffraction peak and its second order counterpart. The results show a remarkable improvement of GO structural order upon 1-Propanol (1-Pr) uptake, as well as a non-trivial dynamics of the 1-Pr intercalated in GO: we observed an ordering transition of the 2D molecular packing that triggers the formation of 1-Pr bilayers. Furthermore, upon 1-Pr desorption, a stable “dry” intercalate with excellent structural order is achieved, opening a promising procedure for the development of layered carbon nanomaterials with tailored pore sizes.