Novel BN Hollow Microspheres with Open Mouths – Facile Synthesis, Growth Mechanism, Resonant Raman Scattering Effect, and Cathodoluminescence Performance

Abstract

AbstractNovel BN hollow microspheres have been successfully fabricated by a facile chemical vapour reaction approach using ammonia–borane as a precursor. The morphology and structure of the as‐synthesized products are characterized by scanning electron microscopy (SEM), high‐resolution transmission electron microscopy (HRTEM), selected‐area electron diffraction (SAED), as well as electron energy loss spectroscopy (EELS). The hollow microspheres have open mouths and are 0.5–6 μm in diameter. The walls of the hollow spheres with thicknesses ranging from 200 to 800 nm are composed of poorly crystallized BN. The growth mechanism of the hollow microspheres is investigated and a growth model is proposed. The BN hollow spheres show pronounced resonant Raman scattering character under illumination of a 457.9 nm laser line, which implies a potential photothermal effect. The hollow microspheres also exhibit intense cathodoluminescence emissions in the region of 200–400 nm, indicating that they could be potentially used as compact ultraviolet laser emitters. Moreover, the unique open‐mouth feature, in combination with the superior thermal and chemical stability of BN, makes the BN hollow microspheres potential candidates as microreactors for investigations of high‐temperature space‐confined chemical reactions.