Inorganic nanotubes are morphological counterparts of carbon nanotubes (CNTs). Yet, only graphene-like BN layer has been readily organized into single walled nanotubes so far. In this study, we present a simple route to obtain inorganic single walled nanotubes - a novel ultrathin morphology for bismuth iodide (BiI3), embedded within CNTs. The synthesis involves the capillary filling of BiI3 into CNT, which acts as a nanotemplate, by annealing the BiI3-CNT mixture above the melting point of BiI3. Aberration corrected scanning/transmission electron microscopy is used in characterizing the novel morphology of BiI3. A critical diameter which enables the formation of BiI3 nanotubes, against BiI3 nanorods is identified. The relative stability of these phases is investigated with the density functional theory calculations. Remarkably, the calculations reveal that the single walled BiI3 nanotubes are semiconductors with a direct band gap, which remain stable even without the host CNTs.

The melt phase encapsulation of gadolinium iodide (GdI 3) in small internal diameter carbon nanotubes (CNT) 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 mono-elemental 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 GdI 3 encapsulation in CNTs as a function of the host's internal diameter.

Aluminosilicate spheres with a macroporous core and mesoporous shell (Si/Al ratio of 11) is synthesised by a sol‐gel method utilizing cetyltrimethyl ammonium bromide (CTAB) as a structure directing agent in basic medium. The selective incorporation of aluminium in the silica matrix results in the formation of aluminosilicates with an overall acidity of 0.32 mmol/g with interconnected pores. Direct N‐alkylation reaction is a prototype of C−N bond formation reaction and meso‐ macroporous aluminosilicate is shown to catalyze this reaction with excellent yield. The catalyst is tested and found sustainable for five catalytic cycles even without any high temperature regeneration step.