Well crystallized nanoscale tubular materials have been synthesized via the reaction of ${\mathrm{TiO}}_2$ crystals of either anatase or rutile phase and NaOH aqueous solution. The atomic structure of the synthesized tubular material is imaged by high-resolution transmission electron microscopy (HRTEM), and the composition of individual tubular structures is determined using selected area energy dispersive X-ray spectroscopy (EDX). Our results show that the tubular materials are well crystallized tubes with an average diameter of about 9 nm and little dispersion, and are composed of mainly titanium and oxygen. The atomic ratio of O/Ti is found, however, to vary from tube to tube. Detailed electron and x-ray diffraction studies show that the structure of our titanium oxide nanotubes do not agree with those made of ${\mathrm{TiO}}_2$ crystals with either anatase or rutile phase. HRTEM observations revealed that the titanium oxide nanotubes usually have multiple shells, in analogy with multiwalled carbon nanotubes, but the shell spacing is about 0.75 nm which is much larger than that of the carbon nanotube, and the atomic structures of different shells are well correlated.

Monolayer transition metal dichalcogenides (TMDs) have become essential two-dimensional materials for their perspectives in engineering next-generation electronics. For related applications, the controlled growth of large-area uniform monolayer TMDs is crucial, while it remains challenging. Herein, we report the direct synthesis of 6-inch uniform monolayer molybdenum disulfide on the solid soda-lime glass, through a designed face-to-face metal-precursor supply route in a facile chemical vapor deposition process. We find that the highly uniform monolayer film, with the composite domains possessing an edge length larger than 400 µm, can be achieved within a quite short time of 8 min. This highly efficient growth is proven to be facilitated by sodium catalysts that are homogenously distributed in glass, according to our experimental facts and density functional theory calculations. This work provides insights into the batch production of highly uniform TMD films on the functional glass substrate with the advantages of low cost, easily transferrable, and compatible with direct applications.