Monodispersed, agglomerate‐free In2O3 hollow spheres have been prepared via a simple synthetic route involving permeation and anchoring of In3+ ions with carbonyl groups of swollen commercial polymer beads in tetrachloroethylene solvent followed by thermal removal of the template cores in ambient air. The as‐synthesized hollow spheres exhibit a narrow size distribution with tunable particle size (0.5–1.2 μm) and shell thickness (62–230 nm) over the process variables examined, i.e., InCl3 precursor concentration (4.5 × 10−3–6.7 × 10−2 M), reaction temperature (55°C–95°C), and reaction time (1–6 h). Kinetics calculation reveals that the formation of permeating In3+‐rich shell in the swollen template beads becomes energetically less favorable to proceed as the reaction time increases. This limits the maximum shell thickness attainable at the given process variables. The shell is nanoporous with a Horvath‐Kawazoe (HK) pore size of ~3 nm, which remains essentially unchanged as the process variables alter. The In2O3 hollow spheres with an increased Brunauer‐Emmett‐Teller (BET) surface area (up to 329 m2/g) show an improved capability in photodegradation of aqueous methylene blue (MB) dye under UV exposure as well as an increased sensitivity for CO‐gas detection. This metal‐implantation scheme is general and can be extended to the synthesis of other hollow materials in various solvent liquids.

No abstract

No abstract

No abstract

Silver nanoparticles were adsorbed preferentially on silica surface to form composite particles using a reverse micelle process that stabilizes the silver particles by an anionic sodium bis(2-ethylhexyl) sulfosuccinate (AOT) surfactant in isooctane solvent together with the silica particles in which their surface being mediated by a cationic poly(allylamine hydrochloride) (PAH) polyelectrolyte. The heterogeneous adsorption was rendered by both electrostatic attraction and hydrophilic/hydrophobic interaction, and was carried out in multiple deposition cycles. The resulting nanocomposite particles were characterized by zeta-potential measurement, electron microscopy, X-ray diffractometry, field-emission electron spectroscopy for chemical analysis (ESCA), and inductively coupled plasma analysis, respectively. In addition, antibacterial activity of the composite particles was examined against Escherichia coli (E. coli) in aqueous environment.