Room temperature crystallization of highly luminescent lanthanide-doped CaF<sub>2</sub> in nanosized droplets: first example of the synthesis of metal halogenide in miniemulsion with effective doping and size control

Dolcet, Paolo; Mambrini, Antonin; Pedroni, Marco; Speghini, Adolfo; Gialanella, Stefano; Casarin, Maurizio; Gross, Silvia

doi:10.1039/c4ra12006j

Cited by 33 publications

(20 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[19] Thep osition of the A 1g band cannot be identified in our data, probably because polarization phenomena, to which the A 1g band is sensitive due to the random orientation of the flakes of the material (powder sample), cause af urther intensity reduction of the already weak peak. [20] Moreover the absence of the characteristic CaF 2 peak [21] at 321 cm À1 agrees with the XRD and EDX results in confirming the purity of the material and the successful removal of salts through EDTAtreatment. TheFT-IR spectrum of b-CaGe 2 ( Figure S2) showed very broad features and no distinctive bands could be identified in the 400-4000 cm À1 region, in agreement with previous reports.…”

Section: Resultssupporting

confidence: 81%

Synthesis of 2D Germanane (GeH): a New, Fast, and Facile Approach

et al. 2020

View full text Add to dashboard Cite

Germanane (GeH), ag ermanium analogue of graphane,h as recently attracted considerable interest because its remarkable combination of properties makes it an extremely suitable candidate to be used as 2D material for field effect devices,p hotovoltaics,a nd photocatalysis.U pt on ow,t he synthesis of GeH has been conducted by substituting Ca by H in a b-CaGe 2 layered Zintl phase through topochemical deintercalation in aqueous HCl. This reaction is generally slow and takes place over 6t o1 4days. The new and facile protocol presented here allows to synthesize GeH at room temperature in as ignificantly shorter time (a few minutes), which renders this method highly attractive for technological applications.T he GeH produced with this method is highly pure and has aband gap (E g)close to 1.4 eV,alower value than that reported for germanane synthesized using HCl, whichi s promising for incorporation of GeH in solar cells.

show abstract

Section: Resultssupporting

confidence: 81%

Synthesis of 2D Germanane (GeH): a New, Fast, and Facile Approach

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Alkaline earth fluoride materials have attracted great attention due to a wide variety of applications in dielectrics, optics, optoelectronics, and photonics . In particular, calcium fluoride has been regarded as one of the most efficient hosts for upconversion (UC) or downconversion emissions, also due to its low phonon energy, which minimizes nonradiative de‐excitation processes .…”

Section: Values Of the A‐axis Parameters Of The Caf2:yb3+ Er3+ Filmsmentioning

confidence: 99%

Nanostructured CaF₂:Ln³⁺ (Ln³⁺ = Yb³⁺/Er³⁺, Yb³⁺/Tm³⁺) Thin Films: MOCVD Fabrication and Their Upconversion Properties

Pellegrino

Cortelletti

Pedroni

et al. 2017

Adv Materials Inter

Self Cite

View full text Add to dashboard Cite

it possible to collect the radiation energy outside the absorption range of the photoactive material (usually silicon) by shifting its energy to a more suitable optical region. In addition, rare-earth doped CaF 2 compounds are promising luminescent materials as phosphors and in technological applications as micro-and nanoscale thermometry for microelectronics and for biomedical assays. [4,[16][17][18] A comment deserves the CaF 2 structure, also in view of similar ionic size of the trivalent lanthanide ions, inserted as dopants, and the Ca 2+ ion. Calcium fluoride has the typical fluorite structure, following the name (fluorite) of the mineral form of CaF 2 , which is a simple cubic arrangement of anions with 50% cubic sites filled with Ca 2+ . Thus, in this structure, calcium is eight coordinated by fluoride ions, a coordination environment suitable for the lanthanide ions, being eight one of the most common coordination number for lanthanides. [19] Most of the above-mentioned applications require the calcium fluoride material in the form of thin films. Several studies are available on the deposition of CaF 2 thin films using physical vapor deposition techniques, such as sputtering, [20,21] electron beam evaporation, [22] pulsed laser deposition, [23,24] and molecular beam epitaxy. [25,26] Calcium fluoride films have also been deposited through sol-gel chemical routes using spin coating [27] or dip coating. [28] Among the chemical vapor deposition approaches, atomic layer deposition has been applied to the deposition of CaF 2 films. [29] Nevertheless, even though various deposition methods have been applied to the fabrication of CaF 2 films, a more versatile, easily scalable, fast, and industrially appealing approach is highly desirable.The metal organic chemical vapor deposition (MOCVD) has the potential advantage of being a very reliable and reproducible method for the fast production of films with high uniformity degree in both thickness and composition over large areas. In addition, note that in the case of potential integration of these layers in photovoltaic cell production, plasma-enhanced CVD is the most common fabrication method for thin film Si-based cells. [30] Calcium fluoride represents one of the most efficient hosts for up-conversion or down-conversion emissions. A simple metal organic chemical vapor deposition approach is applied to the fabrication of CaF 2 nanostructured thin films using the fluorinated "second-generation" β-diketonate compound Ca (hfa) 2 •diglyme•H 2 O as a Ca-F single-source precursor. The versatility of the process is demonstrated for the fabrication of up-converting Yb/Er or Yb/Tm codoped CaF 2 films on Si, quartz, and glass substrates. The Ln(hfa) 3 •diglyme (Ln = Tm, Er, Yb) precursors are used as sources of the doping ions. Structural, morphological, and compositional characterization of the films shows the formation of polycrystalline CaF 2 films with a very uniform surface and suitable doping. In fact, an appropriate tuning of the mixture composition, i.e., the Ca:Ln ...

show abstract

“…Our results show that trinuclear copper(II) complexes are the major species observed in the range of 2:1 to 4:1 metal to ligand ratio. The Cu/ Aβ(1-16) dimer revealed a distinct Cu(II) coordination mode with respect to the Aβ (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16) monomer. This finding may be of relevance considering the greater toxicity of lowmolecular-weight Aβ oligomers in AD.…”

Section: P13 New Alkynyl-gold(i) Complexes Featuring Anti-cancer Actimentioning

confidence: 99%

“…In this framework, to achieve crystallisation through the use of low temperature and sustainable processes based on cheap and safe chemicals represents a challenging playground in modern inorganic chemistry [1,2]. In these last years, we have developed in our group different low temperature (T<150°C) wet and green chemistry routes [3] to prepare different inorganic functional nanomaterials, ranging from i) ferrites [4], to manganites [5], to pure and doped ii) transition metal metal oxides [6][7][8], sulphides [9][10] and halogenides [11], to iii) metal/metal oxide nanocomposites [10]. The adopted wet chemistry routes are i) miniemulsions [3, 6-7, 9, 11,12], affording crystallisation in confined space and typically at room temperature, ii) coprecipitation combined with hydrothermal route [4][5] to 3) or iii) more classical colloidal routes [8,10], as well as combination thereof.…”

Section: Silvia Grossmentioning

confidence: 99%

Synthesis and characterization of new ferrocene, porphyrin and C60 triads, connected by triple bonds

Tagliatesta

Pizzoferrato

2015

Journal of Organometallic Chemistry

View full text Add to dashboard Cite

Room temperature crystallization of highly luminescent lanthanide-doped CaF₂ in nanosized droplets: first example of the synthesis of metal halogenide in miniemulsion with effective doping and size control

Abstract: We report the first example of crystalline and luminescent lanthanide-doped CaF2 nanostructures synthesised in the confined space of miniemulsion at room temperature.

Cited by 33 publications

References 43 publications

Synthesis of 2D Germanane (GeH): a New, Fast, and Facile Approach

Synthesis of 2D Germanane (GeH): a New, Fast, and Facile Approach

Nanostructured CaF₂:Ln³⁺ (Ln³⁺ = Yb³⁺/Er³⁺, Yb³⁺/Tm³⁺) Thin Films: MOCVD Fabrication and Their Upconversion Properties

Synthesis and characterization of new ferrocene, porphyrin and C60 triads, connected by triple bonds

Contact Info

Product

Resources

About

Room temperature crystallization of highly luminescent lanthanide-doped CaF2 in nanosized droplets: first example of the synthesis of metal halogenide in miniemulsion with effective doping and size control

Abstract: We report the first example of crystalline and luminescent lanthanide-doped CaF2 nanostructures synthesised in the confined space of miniemulsion at room temperature.

Cited by 33 publications

References 43 publications

Synthesis of 2D Germanane (GeH): a New, Fast, and Facile Approach

Synthesis of 2D Germanane (GeH): a New, Fast, and Facile Approach

Nanostructured CaF2:Ln3+ (Ln3+ = Yb3+/Er3+, Yb3+/Tm3+) Thin Films: MOCVD Fabrication and Their Upconversion Properties

Synthesis and characterization of new ferrocene, porphyrin and C60 triads, connected by triple bonds

Contact Info

Product

Resources

About

Room temperature crystallization of highly luminescent lanthanide-doped CaF₂ in nanosized droplets: first example of the synthesis of metal halogenide in miniemulsion with effective doping and size control

Nanostructured CaF₂:Ln³⁺ (Ln³⁺ = Yb³⁺/Er³⁺, Yb³⁺/Tm³⁺) Thin Films: MOCVD Fabrication and Their Upconversion Properties