Hybrid Germanium Nanoparticle–Single-Wall Carbon Nanotube Free-Standing Anodes for Lithium Ion Batteries

Germanium nanoparticles (Ge-NPs) were synthesized through a one-step chemical vapor deposition process and were included in a hybrid free-standing single-wall carbon nanotube (SWCNT) electrode. The Ge-NPs were characterized through scanning electron microscopy and Raman spectroscopy to confirm the presence of crystalline nanoparticles with average diameters of 60 nm. Electrochemical testing of the Ge-NPs shows high reversible lithium ion capacity up to 900 mAh g–1 and a Coulombic efficiency of 96% on the first cycle, with capacities realizing 1000 mAh g–1 and a Coulombic efficiency of 98% on the second cycle. The use of SWCNTs to provide a stable nanoscale electrical network to support Ge-NPs resulted in a hybrid three-dimensional free-standing electrode, which is an attractive alternative to the conventional composite-current collector approach. The Ge-NP:SWCNT hybrid electrode with thin film titanium contacts produced electrode capacities of 983 mAh g–1 versus Li/Li+ up to 3 V. The higher anode capacity...

[1]  Kunio Nishimura,et al.  Recent development of carbon materials for Li ion batteries , 2000 .

[2]  R. Andrews,et al.  Single-step synthesis of germanium nanowires encapsulated within multi-walled carbon nanotubes , 2009 .

[3]  A. R. Ramos,et al.  Raman and XRD studies of Ge nanocrystals in alumina films grown by RF-magnetron sputtering , 2008 .

[4]  C. C. Ahn,et al.  Nanocrystalline and Thin Film Germanium Electrodes with High Lithium Capacity and High Rate Capabilities , 2004 .

[5]  B. Landi,et al.  Thermal Oxidation Profiling of Single-Walled Carbon Nanotubes , 2005 .

[6]  P. Bruce,et al.  Nanostructured materials for advanced energy conversion and storage devices , 2005, Nature materials.

[7]  Brian J Landi,et al.  Purity assessment of single-wall carbon nanotubes, using optical absorption spectroscopy. , 2005, The journal of physical chemistry. B.

[8]  Chunjoong Kim,et al.  Electrochemical performance of amorphous-silicon thin films for lithium rechargeable batteries , 2006 .

[9]  Ya-pu Zhao,et al.  Silicon nanowire reinforced by single-walled carbon nanotube and its applications to anti-pulverization electrode in lithium ion battery , 2012 .

[10]  J. Tarascon,et al.  Si Electrodes for Li-Ion batteries- A new way to look at an old problem , 2008 .

[11]  Jaephil Cho,et al.  Surface-stabilized amorphous germanium nanoparticles for lithium-storage material. , 2005, The journal of physical chemistry. B.

[12]  B. Landi,et al.  High energy density lithium-ion batteries with carbon nanotube anodes , 2010 .

[13]  Reginald E. Rogers,et al.  Enhanced capacity and rate capability of carbon nanotube based anodes with titanium contacts for lithium ion batteries. , 2010, ACS nano.

[14]  Cheol‐Min Park,et al.  Electrochemical Characterizations of Germanium and Carbon-Coated Germanium Composite Anode for Lithium-Ion Batteries , 2008 .

[15]  Jaephil Cho,et al.  High performance Ge nanowire anode sheathed with carbon for lithium rechargeable batteries , 2011 .

[16]  H. Kwon,et al.  Preparation of single-walled carbon nanotube/silicon composites and their lithium storage properties. , 2011, ACS applied materials & interfaces.

[17]  Yi Cui,et al.  Light-weight free-standing carbon nanotube-silicon films for anodes of lithium ion batteries. , 2010, ACS nano.

[18]  B. Landi,et al.  Germanium-single-wall carbon nanotube anodes for lithium ion batteries , 2010 .

[19]  Ryne P. Raffaelle,et al.  Carbon nanotubes for lithium ion batteries , 2009 .

[20]  B. A. Weinstein,et al.  Second-Order Raman Spectrum of Germanium , 1973 .

[21]  Zhixin Chen,et al.  Silicon/Single-Walled Carbon Nanotube Composite Paper as a Flexible Anode Material for Lithium Ion Batteries , 2010 .

[22]  T. Takamura,et al.  A thin film silicon anode for Li-ion batteries having a very large specific capacity and long cycle life , 2004 .

[23]  A. Sammells,et al.  Thermodynamic Studies of Li‐Ge Alloys: Application to Negative Electrodes for Molten Salt Batteries , 1982 .

[24]  Ryne P. Raffaelle,et al.  Lithium Ion Capacity of Single Wall Carbon Nanotube Paper Electrodes , 2008 .

[25]  Yi Cui,et al.  High capacity Li ion battery anodes using ge nanowires. , 2008, Nano letters.