The Formation of Well‐Defined Hollow Silica Spheres with Multilamellar Shell Structure

Abstract

determined to be 50 and 2000 , respectively, using a calibrated oscillating quartz crystal thickness monitor. After deposition, the devices were encapsulated with epoxy (Loctite quick-set epoxy) under an argon atmosphere in order to minimize exposure to oxygen and moisture. All device measurements were made at room temperature.Photoluminescence and electroluminescence spectra were measured on a SPEX Fluorolog-2 equipped with a liquid N 2 cooled InGaAs detector (800± 1600 nm), or on a spectrometer consisting of an ISA-SPEX Triax 180 spectrograph equipped with a liquid N 2 cooled CCD detector (Hamamatsu CCD, 1024 64 pixel, 400±1100 nm). Emission quantum yields were measured by relative actinometry with H 2 TPP (u = 0.11) or ZnTPP (u = 0.033). Near-IR quantum yields were determined for Yb(TPP)L(OEt) on the CCD fluorescence system using the visible H 2 TPP and ZnTPP actinometers. Then the emission quantum yields for the Nd and Er complexes were determined relative to the Yb(TPP)L(OEt) using the SPEX Fluorolog-2 with the InGaAs detector.Power for electroluminescence (EL) measurements was supplied using a Keithley 228 voltage/current source. A 100 W primary standard quartz halogen lamp was used to calibrate the Triax 180 spectrograph/CCD detector system in irradiance units (lW cm 2 nm ±1 ). Measurements were made normal to the surface of the devices, and in the computation of the EL quantum efficiencies it was assumed that the spatial distribution of the emission was Lambertian [23]. External device quantum efficiencies were calculated as described in the literature [27].

Polymer–inorganic microcapsules fabricated by combining biomimetic adhesion and bioinspired mineralization and their use for catalase immobilization

“…Among, bioinspired mineralization, a process mimic of biomineralization by which soft living organisms create hierarchical hybrid materials [18], has been extensively investigated during the past two decades and already utilized for the preparation of microcapsules. Till now, inorganic oxides [19][20][21] (such as silica, and titania) and calcium salts [22,23] (such as calcium carbonate and calcium phosphate) as two typical minerals, have been successfully incorporated into the capsule wall through bioinspired mineralization. Considering the pH-dependent solubility of calcium salts, microcapsules composed of these calcium salts would be dissolved under acidic conditions.…”

Synthesis and Applications of Hollow Particles

“…The reports on preparation of hollow SiO 2 particles by emulsion template method also include reference 55) to reference 58) . 62) reported a flexible approach to produce hollow elastic capsules, with size ranging from micrometers to millimeters.…”

Novel manufacturing process of hollow polymer microspheres

“…Selfassembly of nanoparticles to form microspheres, in which the cores have been removed are described in Boal et al (2004) and Dinsmore et al (2002). Furthermore, particles with solid cores and solid shells that are made of different materials (Berkland et al, 2004;Sun et al, 2003) could be used. Removing the core with thermal energy by heating or using a solvent results in hollow gas-filled particles (Zhong et al, 2000).…”