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Monodisperse colloidal gallium nanoparticles: synthesis, low temperature crystallization, surface plasmon resonance and Li-ion storage.

Yarema M, Wörle M, Rossell MD, Erni R, Caputo R, Protesescu L, Kravchyk KV, Dirin DN, Lienau K, von Rohr F, Schilling A, Nachtegaal M, Kovalenko MV - J. Am. Chem. Soc. (2014)

Bottom Line: The results point to delta (δ)-Ga polymorph as a single low-temperature phase, while phase transition is characterized by the large hysteresis and by the large undercooling of crystallization and melting points down to 140-145 and 240-250 K, respectively.We have observed size-tunable plasmon resonance in the ultraviolet and visible spectral regions.We also report stable operation of Ga nanoparticles as anode material for Li-ion batteries with storage capacities of 600 mAh g(-1), 50% higher than those achieved for bulk Ga under identical testing conditions.

View Article: PubMed Central - PubMed

Affiliation: Laboratory for Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich , CH-8093 Zürich, Switzerland.

ABSTRACT
We report a facile colloidal synthesis of gallium (Ga) nanoparticles with the mean size tunable in the range of 12-46 nm and with excellent size distribution as small as 7-8%. When stored under ambient conditions, Ga nanoparticles remain stable for months due to the formation of native and passivating Ga-oxide layer (2-3 nm). The mechanism of Ga nanoparticles formation is elucidated using nuclear magnetic resonance spectroscopy and with molecular dynamics simulations. Size-dependent crystallization and melting of Ga nanoparticles in the temperature range of 98-298 K are studied with X-ray powder diffraction, specific heat measurements, transmission electron microscopy, and X-ray absorption spectroscopy. The results point to delta (δ)-Ga polymorph as a single low-temperature phase, while phase transition is characterized by the large hysteresis and by the large undercooling of crystallization and melting points down to 140-145 and 240-250 K, respectively. We have observed size-tunable plasmon resonance in the ultraviolet and visible spectral regions. We also report stable operation of Ga nanoparticles as anode material for Li-ion batteries with storage capacities of 600 mAh g(-1), 50% higher than those achieved for bulk Ga under identical testing conditions.

No MeSH data available.


Related in: MedlinePlus

Ga–Ga distances for two shells,extracted from the bestfits of EXAFS spectra at different temperatures. CN is coordinationnumber.
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fig6: Ga–Ga distances for two shells,extracted from the bestfits of EXAFS spectra at different temperatures. CN is coordinationnumber.

Mentions: The temperature-dependent EXAFSspectra are shown in Figure S19 togetherwith the best fit curves.Figure 6 represents the extracted Ga–Gadistances for two averaged Ga shells. Abrupt changes of Ga–Gadistances happen between 148 and 98 K upon cooling and between 198and 248 K upon heating. Being in good correspondence to other methods,these changes are attributed here to freezing and melting phase transitionsof Ga NPs. The Ga–Ga distances in metallic Ga at T = 98, 148 (during heating), and 198 K (during heating) match wellwith the Ga–Ga distances in the δ-Ga crystal structure(Table S8 and ref (22)). For all other temperatures,the Ga–Ga distances remain smaller than that of α-Ga,confirming the liquid state of Ga NPs. Overall, the combined resultsof XRD, TEM, specific heat, and EXAFS measurements point to a strongtendency to overcooling, a large hysteresis between crystallizationand melting and the absence of the stable α-Ga modificationbut formation of only δ-Ga polymorph for crystallized Ga NPsin the studied size range of 12–46 nm.2,4c,6a,20a−20c


Monodisperse colloidal gallium nanoparticles: synthesis, low temperature crystallization, surface plasmon resonance and Li-ion storage.

Yarema M, Wörle M, Rossell MD, Erni R, Caputo R, Protesescu L, Kravchyk KV, Dirin DN, Lienau K, von Rohr F, Schilling A, Nachtegaal M, Kovalenko MV - J. Am. Chem. Soc. (2014)

Ga–Ga distances for two shells,extracted from the bestfits of EXAFS spectra at different temperatures. CN is coordinationnumber.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4525770&req=5

fig6: Ga–Ga distances for two shells,extracted from the bestfits of EXAFS spectra at different temperatures. CN is coordinationnumber.
Mentions: The temperature-dependent EXAFSspectra are shown in Figure S19 togetherwith the best fit curves.Figure 6 represents the extracted Ga–Gadistances for two averaged Ga shells. Abrupt changes of Ga–Gadistances happen between 148 and 98 K upon cooling and between 198and 248 K upon heating. Being in good correspondence to other methods,these changes are attributed here to freezing and melting phase transitionsof Ga NPs. The Ga–Ga distances in metallic Ga at T = 98, 148 (during heating), and 198 K (during heating) match wellwith the Ga–Ga distances in the δ-Ga crystal structure(Table S8 and ref (22)). For all other temperatures,the Ga–Ga distances remain smaller than that of α-Ga,confirming the liquid state of Ga NPs. Overall, the combined resultsof XRD, TEM, specific heat, and EXAFS measurements point to a strongtendency to overcooling, a large hysteresis between crystallizationand melting and the absence of the stable α-Ga modificationbut formation of only δ-Ga polymorph for crystallized Ga NPsin the studied size range of 12–46 nm.2,4c,6a,20a−20c

Bottom Line: The results point to delta (δ)-Ga polymorph as a single low-temperature phase, while phase transition is characterized by the large hysteresis and by the large undercooling of crystallization and melting points down to 140-145 and 240-250 K, respectively.We have observed size-tunable plasmon resonance in the ultraviolet and visible spectral regions.We also report stable operation of Ga nanoparticles as anode material for Li-ion batteries with storage capacities of 600 mAh g(-1), 50% higher than those achieved for bulk Ga under identical testing conditions.

View Article: PubMed Central - PubMed

Affiliation: Laboratory for Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich , CH-8093 Zürich, Switzerland.

ABSTRACT
We report a facile colloidal synthesis of gallium (Ga) nanoparticles with the mean size tunable in the range of 12-46 nm and with excellent size distribution as small as 7-8%. When stored under ambient conditions, Ga nanoparticles remain stable for months due to the formation of native and passivating Ga-oxide layer (2-3 nm). The mechanism of Ga nanoparticles formation is elucidated using nuclear magnetic resonance spectroscopy and with molecular dynamics simulations. Size-dependent crystallization and melting of Ga nanoparticles in the temperature range of 98-298 K are studied with X-ray powder diffraction, specific heat measurements, transmission electron microscopy, and X-ray absorption spectroscopy. The results point to delta (δ)-Ga polymorph as a single low-temperature phase, while phase transition is characterized by the large hysteresis and by the large undercooling of crystallization and melting points down to 140-145 and 240-250 K, respectively. We have observed size-tunable plasmon resonance in the ultraviolet and visible spectral regions. We also report stable operation of Ga nanoparticles as anode material for Li-ion batteries with storage capacities of 600 mAh g(-1), 50% higher than those achieved for bulk Ga under identical testing conditions.

No MeSH data available.


Related in: MedlinePlus