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Silicon carbide-free graphene growth on silicon for lithium-ion battery with high volumetric energy density.

Son IH, Hwan Park J, Kwon S, Park S, Rümmeli MH, Bachmatiuk A, Song HJ, Ku J, Choi JW, Choi JM, Doo SG, Chang H - Nat Commun (2015)

Bottom Line: However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life.Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation.The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers.

View Article: PubMed Central - PubMed

Affiliation: Energy Material Lab, Material Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, Republic of Korea.

ABSTRACT
Silicon is receiving discernable attention as an active material for next generation lithium-ion battery anodes because of its unparalleled gravimetric capacity. However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life. Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation. The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers. When paired with a commercial lithium cobalt oxide cathode, the silicon carbide-free graphene coating allows the full cell to reach volumetric energy densities of 972 and 700 Wh l(-1) at first and 200th cycle, respectively, 1.8 and 1.5 times higher than those of current commercial lithium-ion batteries. This observation suggests that two-dimensional layered structure of graphene and its silicon carbide-free integration with silicon can serve as a prototype in advancing silicon anodes to commercially viable technology.

No MeSH data available.


Related in: MedlinePlus

Verification of SiC-free growth.(a) X-ray photoelectron spectroscopy spectra in Si 2p band for Gr–Si, SiC–Si, AC–Si and pristine Si. (b) A scanning TEM image of a Gr–Si NP. (c) EELS spectra for the spots denoted in b.
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f2: Verification of SiC-free growth.(a) X-ray photoelectron spectroscopy spectra in Si 2p band for Gr–Si, SiC–Si, AC–Si and pristine Si. (b) A scanning TEM image of a Gr–Si NP. (c) EELS spectra for the spots denoted in b.

Mentions: The SiC-free graphene growth was verified by both bulk scale and single-particle scale analyses. X-ray photoelectron spectroscopy profiles in Si 2p band (Fig. 2a) as well as X-ray diffraction (XRD) spectra (Supplementary Fig. 2) show no peaks corresponding to SiC for graphene-coated Si (Gr–Si), AC-coated Si (AC–Si) and pristine Si, in contrast to a control (SiC–Si) sample synthesized through a CO2-free route using CH4 and H2. On the other hand, a scanning TEM imaging using high-angle annular dark field showed that the Si NP have a core–shell structure with brighter core and thin relatively darker shell attributed to a Si core and an oxide coating (Fig. 2b). Electron energy loss spectroscopy (EELS) spectra (Fig. 2c) obtained for multiple spots across the NP did not exhibit any signals28 reflective of SiC formation, confirming SiC-free growth in the current growth process. Also, SiO2 signals at 108 eV were detected at points 1 and 2 more strongly than the other spots in the centre, implying that the SiO2 surface serves as catalytic sites for graphene growth. The persistent presence of the SiO2 surface layers was also verified by XRD (Supplementary Fig. 2) and EELS (Fig. 2b,c) characterization.


Silicon carbide-free graphene growth on silicon for lithium-ion battery with high volumetric energy density.

Son IH, Hwan Park J, Kwon S, Park S, Rümmeli MH, Bachmatiuk A, Song HJ, Ku J, Choi JW, Choi JM, Doo SG, Chang H - Nat Commun (2015)

Verification of SiC-free growth.(a) X-ray photoelectron spectroscopy spectra in Si 2p band for Gr–Si, SiC–Si, AC–Si and pristine Si. (b) A scanning TEM image of a Gr–Si NP. (c) EELS spectra for the spots denoted in b.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4491181&req=5

f2: Verification of SiC-free growth.(a) X-ray photoelectron spectroscopy spectra in Si 2p band for Gr–Si, SiC–Si, AC–Si and pristine Si. (b) A scanning TEM image of a Gr–Si NP. (c) EELS spectra for the spots denoted in b.
Mentions: The SiC-free graphene growth was verified by both bulk scale and single-particle scale analyses. X-ray photoelectron spectroscopy profiles in Si 2p band (Fig. 2a) as well as X-ray diffraction (XRD) spectra (Supplementary Fig. 2) show no peaks corresponding to SiC for graphene-coated Si (Gr–Si), AC-coated Si (AC–Si) and pristine Si, in contrast to a control (SiC–Si) sample synthesized through a CO2-free route using CH4 and H2. On the other hand, a scanning TEM imaging using high-angle annular dark field showed that the Si NP have a core–shell structure with brighter core and thin relatively darker shell attributed to a Si core and an oxide coating (Fig. 2b). Electron energy loss spectroscopy (EELS) spectra (Fig. 2c) obtained for multiple spots across the NP did not exhibit any signals28 reflective of SiC formation, confirming SiC-free growth in the current growth process. Also, SiO2 signals at 108 eV were detected at points 1 and 2 more strongly than the other spots in the centre, implying that the SiO2 surface serves as catalytic sites for graphene growth. The persistent presence of the SiO2 surface layers was also verified by XRD (Supplementary Fig. 2) and EELS (Fig. 2b,c) characterization.

Bottom Line: However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life.Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation.The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers.

View Article: PubMed Central - PubMed

Affiliation: Energy Material Lab, Material Research Center, Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd, 130 Samsung-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-803, Republic of Korea.

ABSTRACT
Silicon is receiving discernable attention as an active material for next generation lithium-ion battery anodes because of its unparalleled gravimetric capacity. However, the large volume change of silicon over charge-discharge cycles weakens its competitiveness in the volumetric energy density and cycle life. Here we report direct graphene growth over silicon nanoparticles without silicon carbide formation. The graphene layers anchored onto the silicon surface accommodate the volume expansion of silicon via a sliding process between adjacent graphene layers. When paired with a commercial lithium cobalt oxide cathode, the silicon carbide-free graphene coating allows the full cell to reach volumetric energy densities of 972 and 700 Wh l(-1) at first and 200th cycle, respectively, 1.8 and 1.5 times higher than those of current commercial lithium-ion batteries. This observation suggests that two-dimensional layered structure of graphene and its silicon carbide-free integration with silicon can serve as a prototype in advancing silicon anodes to commercially viable technology.

No MeSH data available.


Related in: MedlinePlus