Ultimately simple one-pot single-step synthesis of rare earth doped spherical mesoporous metal oxide nanospheres with upconversion emission ability in supercritical methanol

Abstract

ABSTRACT

Synthetic versatility of nanoparticles: A new, rapid, one-pot, single-step synthetic approach to spherical mesoporous (metal) oxide nanoparticles using supercritical alcohols

“…This simple method can also be used for the preparation of upconversion (UC) fluorescent MARIMO NPs via the introduction of appropriate rare earth (RE) elements, such as Er , as dopants into the reaction mixture [77]. It is well known that a smaller phonon energy leads to smaller multiphonon relaxation rates, which improves the fluorescence intensity in UC materials [78].…”

“…The process has been used to prepare ZrO 2 :Er, TiO 2 :Er, TiO 2 :Eu (10:1), TiO 2 :Ce (10:1), TiO 2 :Yb (10:1), and TiO 2 :Fe (10:1) MARIMO NPs using the scMeOH method [77]. Therefore, it has been clearly demonstrated that this synthetic approach is highly versatile for the preparation of MARIMO NPs doped with a wide range of elements.…”

One‐Step Direct Synthesis of SiO2–TiO2 Composite Nanoparticle Assemblies with Hollow Spherical Morphology

“…spherical morphologies. [29][30][31] We named these NP assemblies micro/mesoporously architected roundly integrated metal oxides (MARIMOs). Various MARIMO assemblies such as SiO 2 , TiO 2 , ZnO, ZrO 2 , and CeO 2 , as well as their composites such as TiO 2 -ZnO, TiO 2 -Al 2 O 3 , ZrO 2 -CeO 2 , and In-Ga-Zn oxide, were prepared by a similar method from precursor solutions consisting of mixed metal alkoxides and/or salts, which demonstrates the versatility of the solvothermal method.…”

“…We have recently developed a new solvothermal approach to fabricate metal oxide NP assemblies with solid or hollow spherical morphologies . We named these NP assemblies m icro/ m esoporously a rchitected r oundly i ntegrated m etal o xides (MARIMOs).…”

Rapid One-Pot Solvothermal Batch Synthesis of Porous Nanocrystal Assemblies Composed of Multiple Transition-Metal Elements

“…To overcome the limitations of traditional solution-based syntheses of transition-metal composite oxides with multiple metal components, herein, we demonstrate a rapid one-pot synthetic approach based on a rapid-heating technique in a batch-type reactor to prepare porous metal oxides containing multiple transition-metal species (Figure a). Recently, we demonstrated a new synthetic approach to fabricate porous metal oxides using an alcohol-based solvothermal reaction. − In our method, the methanol-based solvothermal reaction was conducted in a closed reactor consisting of an SUS-316 stainless steel tube with pressure-resistant caps (Figure b). The inner temperature was traced by a thermocouple.…”