Sonochemical Preparation of Hollow Nanospheres and Hollow Nanocrystals

• Published in: Journal of the American Chemical Society Vol. 127; no. 8; pp. 2368 - 2369
• Main Authors: Dhas, N. Arul, Suslick, Kenneth S
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 02.03.2005
• Subjects: Catalysis; Catalysts: preparations and properties; Chemistry; Exact sciences and technology; General and physical chemistry; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Five membered ring; Catalytic reaction; Transition metal Compounds; Molybdenum sulfide; Ultrasonic treatment; Molybdenum oxide; Solid particle; Particle suspension; Experimental study; Supported catalyst; Submicron particle; Thiophene derivatives; Sulfur heterocycle; Spherical particle; Catalyst activity; Hydrodesulfurization
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja049494g

Ceramic hollow spheres of MoS2 and MoO3 were obtained by sonochemical synthesis of MoS2 and MoO3 templated on silica nanoparticles (diameters 50−500 nm) followed by acid etching to remove the silica core. The resulting hollow materials have been characterized by elemental analysis, XPS, SEM, TEM, optical absorption, and hydrodesulfurization (HDS) studies. The TEM studies on the hollow ceramic materials indicate the formation of dispersed free spheres with a hollow core. The hollow materials obtained from thermally treated MoS2/SiO2 (450−700 °C) show the formation of layered MoS2 (lattice fringes ∼6.2 Å) with a wall thickness of 6−8 layers. The MoS2 hollow spheres are extremely active catalysts for the HDS of thiophene. Hollow spheres of MoO3 are prepared in a similar fashion. Surprisingly, upon heating, hollow crystals of MoO3 with sharp-edged truncated cubes containing inner voids are formed from the initial spheres.