Nano-carbon materials anodes

Hu, J., Li, H., and Huang, X. (2007). Electrochemical behavior and microstructure variation of hard carbon nano-spherules as anode material for Li-ion batteries. Soiid State Ionics, 178(3-4) pp. 265-271. 

Yang J, Zhou XY, Li J, Zou Y-L, Tang JJ (2012) Study of nano-porous hard carbons as anode materials for lithium ion batteries. Mater Chem Phys 135 445-450... 

Guo BK, Shu J, Wang ZX, H Y, Shi LH, Liu YN, Chen LQ (2008) Electrochemical reduction of nano-Si02 in hard carbon as anode material for lithium ion batteries. Electrochem Commun 10 1876-1878... 

The raw material for the synthesis was methane. Powder of Nickel carbonyl (NC) or powder of nano-diamond (ND) was the catalyst. Attempts to synthesize pyro-carbon on copper powder were not successful. Powder with the composition 70%PC, 30%NC, and also the set of powders with various ratios of PC and ND were tested. Anodes made of the powder 70PC30NC showed satisfactory cycle behavior and had specific capacity 180 mAh/(g of powder) (260 mA-h/(g 0f carbon)) (Fig. 3a). The anodes made of powder xPCyND, irrespective of the components ratio, had specific capacity... 

In addition, materials prepared by anodization permit the growth of the oxide nanostructured film over a conductive substrate (Ti foil), an important aspect for preparation of robust electrodes. As discussed later, electrical contact with the conductive substrate could be further improved using carbon nano tubes. 

As COR and OER occur simultaneously in the cathode, their kinetics are particularly important in evaluating carbon-support corrosion. The kinetics of OER is material-specific, dependent on catalyst composition and electrode fabrication.35,37 -39 A number of OER kinetics studies were done on Pt metal electrodes.37-39 However, there is a lack of OER kinetics data on electrodes made of Pt nano-particles dispersed on carbon supports. Figure 2 shows the measured OER current density with respect to the overpotential defined by Eq. (6).35 The 02 concentration was measured at the exit of a 50-cm2 cell using a gas chromatograph (GC). The 02 evolution rate (= 02 concentration x cathode flow rate) was then converted to the OER current density, assuming 4e /02 molecule. Diluted H2 (10%) and a thicker membrane (50 p,m) were used in the measurement to minimize H2 crossover from anode to cathode, because H2 would react with 02 evolved at the cathode and incur inaccuracy in the measured OER current density. Figure 2 indicates that the OER... 

Danilov M.O., Melezhyk A.V. Carbon nano-structures as hydrogen-adsorbing materials for battery anodes. Russian J. of Applied Chemistry, 2004, 77(12), 1980-1984. 

Richman EK et al (2008) Ordered mesoporous silicon through magnesium reduction of polymer templated silica thin films. Nano Lett 8(9) 3075-3079 Shen L et al (2012) Magnesiothermically reduced diatomaceous earth as a porous silicon anode material for lithium ion batteries. J Power Sources 213 229-232 Shen X et al (2013) Si/mesoporous carbon composite as an anode material for lithium ion batteries. J Alloys Compounds 552 60-64... 

Kim H, Cho J (2008) Superior lithium electroactive mesoporous Si carbon core-shell nanowires for lithium battery anode material. Nano Lett 8 3688-3691. doi 10.1021/nl801853x... 

Another effective method is to achieve core-shell structured nanocomposites. The shells can be C and SiO. In the case of Carbon-coated nano-Si composite, the preparation is as follows as anode material for LIBs. At first, PAN-coated Si nanoparticles are formed by emulsion polymerization and the PAN-coated precursor is heat-treated under Ar to generate a Si-C core-shell nanocomposite (Fig. 5.4a). The conductive carbon shell envelops the Si nanoparticles and suppresses the aggregation of the Si nanoparticles during electrochemical cycling, subsequently ameliorating the capacity retention of this composite anode material (Fig. 5.4b). 

Ma Y, Ding B, Ji G et al (2013) Carbon-encapsulated F-doped Lt4Ti50i2 as a high rate anode material for LU batteries. ACS Nano 7(12) 10870-10878... 

Zhu G-N, Liu H-J, Zhang J-H et al (2011) Carbon-coated nano-sized Li4Ti50i2 nanoporous micro-sphere as anode material for high-rate lithium-ion batteries. Energy Environ Sci 4 4016 22... 

The application of Sn anodes is still hampered by their inherent poor cycling stability resulting from the large volume change. Several strategies have been proposed to overcome this problem. One of the effective strategy is to prepare intermetallic compounds (M M), which consist of an inactive phase M and an active phase M . Another useful approach is either to disperse the nanometer-sized tin-based materials into a carbon matrix or to prepare the carbon-encapsulated hollow tin nano-particles. The carbon component has good elasticity to effectively accommodate the strain of... 

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