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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

UV–vis absorptionspectra of Ga NPs dispersed in hexane.Inset shows SPR values of all measured samples.
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fig7: UV–vis absorptionspectra of Ga NPs dispersed in hexane.Inset shows SPR values of all measured samples.

Mentions: Here, we report on the size-dependent SPR of colloidal GaNPs measuredfrom colloidally stable dispersions in hexane. Depending upon thesize of Ga NPs varied from 17 to 28 nm (11–22 nm Ga cores,covered with ∼3 nm oxide shells), the peak wavelength of SPRcan be tuned in the range of 4.97–5.24 eV (Figure 7). Larger sizes of Ga NPs were not studied due toinstability of the colloids. Sanz et al. used discrete dipole approximationmethod27 to calculate that a 20 nm Ga NPin vacuum should have a SPR peak energy of ca. 5.7 eV. This valueis expected to red-shift by ca. 0.5 eV due to the coating with Ga2O3, thus providing a good agreement with our results.


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)

UV–vis absorptionspectra of Ga NPs dispersed in hexane.Inset shows SPR values of all measured samples.
© Copyright Policy
Related In: Results  -  Collection

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

fig7: UV–vis absorptionspectra of Ga NPs dispersed in hexane.Inset shows SPR values of all measured samples.
Mentions: Here, we report on the size-dependent SPR of colloidal GaNPs measuredfrom colloidally stable dispersions in hexane. Depending upon thesize of Ga NPs varied from 17 to 28 nm (11–22 nm Ga cores,covered with ∼3 nm oxide shells), the peak wavelength of SPRcan be tuned in the range of 4.97–5.24 eV (Figure 7). Larger sizes of Ga NPs were not studied due toinstability of the colloids. Sanz et al. used discrete dipole approximationmethod27 to calculate that a 20 nm Ga NPin vacuum should have a SPR peak energy of ca. 5.7 eV. This valueis expected to red-shift by ca. 0.5 eV due to the coating with Ga2O3, thus providing a good agreement with our results.

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