Morphological Phase Diagram of Gadolinium Iodide Encapsulated in Carbon Nanotubes

Abstract

The melt phase encapsulation of gadolinium iodide (GdI3) in small internal diameter carbon nanotubes (CNTs) was explored to understand how the tubular structure of the host could chemically stabilize a hygroscopic metal halide. However, given the distribution of diameters in the as-received CNTs, the final sample consisted of mixed encapsulation products. These varied from the monoelemental iodine chain to the atomic layer deposition of the binary halide. Supported by density functional theory calculations, these observations led to the proposition of a morphological phase diagram for GdI3 encapsulation in CNTs as a function of the host's internal diameter.