Preparation of Inorganic Hollow Spheres Based on Different Methods

Abstract

Hollow spheres have attracted considerable attention because of their promising applications in the field of nanoscale chemical reactors, catalysts, drug‐delivery carriers, and photonic building blocks. Up to date, numerous approaches have been developed to synthesize hollow spheres, which can be classified as the hard template, soft template and template free routes. Here, we review recent progress and advances that have been made on preparation of hollow inorganic spheres based on the hard template, soft template and template free methods.

Li‐ion batteries: basics, progress, and challenges

“…Again, one popular strategy is to prepare iron oxide materials in nanoscale with tailored morphologies and synthesize iron oxide/carbon composites to accommodate the volume changes as well as improve conductivity. Various iron oxides with different nanostructures have been synthesized, including nanoparticles [92], nanowires [93][94][95], nanobelts [94,96], nanorods [97][98][99], nanotubes [100,101], nanoflakes [102], nanodisks [103] and nanorings [104], nanocubes [105][106][107], nanospheres [108][109][110][111], nanospindles [108,112], nanourchins [113], and nanoflowers [103,108,[114][115][116][117][118][119]. Hollow structured iron oxides are of great interest as the space could, ideally, accommodate the volume expansion during Li insertion [108,[115][116][117][118][119].…”

A simple green approach to synthesis of sub-100 nm carbon spheres as template for TiO2 hollow nanospheres with enhanced photocatalytic activities

“…charge separation efficiency [35]. That is to say, the separation efficiency of photogenerated electron-hole pairs can be effectively promoted in these HTNSs samples with thin shell structures; especially for HTNS-40 with the shell thickness of < 5 nm, the charge recombination could be effectively inhibited, due to the greatly shortened distance for charge carriers to transport to the surface, thus improving the charge separation efficiency [35][36][37][38].…”

Approachable Way to Synthesize 3D Silica Hollow Nanospheres with Mesoporous Shells via Simple Template‐Assisted Technique

“…There a great many different physicochemical methods used to fabricate a wide variety of hollow particles, including sol‐gel process, surface polymerization processes, surfactant assisted solvothermal decomposition, colloidal templating techniques and template free approaches . In general, the most efficient approach, for the production of hollow micro‐/nanoparticles, is by far the sacrificial templating approach.…”

“…It is usually based on the production of core@shell composite particles. Then, the selective removal of the core is achieved by soaking the formed composite material in solvent or heat . The advantage of template directed synthesis approach is ascribed to the ease of the manipulation of hollow materials.…”

“…In this approach the size and the shape of the hollow materials are determined by the shape and size of the template. The sacrificial templates which used to fabricate inorganic hollow particles usually are classified into two main categories, (i) hard (inorganic or organic solid particles), and (ii) soft templates (surfactant vesicles, polymer micelles, microemulsion droplets and gas bubbles) …”