A general method for the synthesis of metal oxide hollow spheres has been developed by using carbonaceous polysaccharide microspheres prepared from saccharide solution as templates. Hollow spheres of a series of metal oxides (SnO2, Al2O3, Ga2O3, CoO, NiO, Mn3O4, Cr2O3, La2O3, Y2O3, Lu2O3, CeO2, TiO2, and ZrO2) have been prepared in this way. The method involves the initial absorption of metal ions from solution into the functional surface layer of carbonaceous saccharide microspheres; these are then densified and cross-linked in a subsequent calcination and oxidation procedure to form metal oxide hollow spheres. Metal salts are used as starting materials, which widens the accessible field of metal oxide hollow spheres. The carbonaceous colloids used as templates have integral and uniform surface functional layers, which makes surface modification unnecessary and ensures homogeneity of the shell. Macroporous films or cheese-like nanostructures of oxides can also be prepared by slightly modified procedures. XRD, TEM, HRTEM, and SAED have been used to characterize the structures. In a preliminary study on the gas sensitivity of SnO2 hollow spheres, considerably reduced "recovery times" were noted, exemplifying the distinct properties imparted by the hollow structure. These hollow or porous nanostructures have the potential for diverse applications, such as in gas sensitivity or catalysis, or as advanced ceramic materials.
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http://dx.doi.org/10.1002/chem.200500660 | DOI Listing |
J Am Chem Soc
January 2025
National Center for International Research on Green Optoelectronics, Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, Institute of Electronic Paper Displays, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China.
Ice melting, a common yet complex phenomenon, remains incompletely understood. While theoretical studies suggest that preexisting defects in ice generate "off-lattice" water molecules, triggering bulk ice melting, direct experimental evidence of their form has been lacking as the transparent and transient nature of ice poses significant challenges for observation with current techniques. Here, we introduce an ice-melting-induced lyophilization (IMIL) technique that employs graphene-based nanoprobes to replicate and track liquid evolution within melting bulk ice.
View Article and Find Full Text PDFChem Asian J
January 2025
Fudan University, Department of Chemistry, 2005# Songhu RD., 200438, Shanghai, CHINA.
Traditional photocatalysts often have limited efficiency due to the high recombination rate of photogenerated electron-hole pairs. In this work, we synthesized 3D/2D ZnSe-MXene heterojunctions by an in situ electrostatic self-assembly method. Notably, the 3% MXene-ZnSe composite exhibited an optimized photocatalytic hydrogen production rate of 765.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Department of Chemistry, Institute for Advanced Materials and Manufacturing, University of Tennessee, Knoxville, Tennessee 37996, United States.
Porous liquids have traditionally been designed with sterically hindered solvents. Alternatively, recent efforts rely on dispersing microporous frameworks in simpler solvents like water. Here we report a unique strategy to construct macroporous water by selectively incorporating hydrophilicity on the surfaces of hydrophobic hollow carbon spheres (HCS).
View Article and Find Full Text PDFDalton Trans
January 2025
Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Third Hospital of Shanxi Medical University, Tongji Shanxi Hospital, Taiyuan, 030032, China.
ACS Omega
December 2024
Department of Physics, School of Advanced Sciences, Vellore Institute of Technology (VIT) Chennai, Vandalur - Kelambakkam Road, Chennai 600127, India.
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