Four types of size-controlled SnO2 nanoparticles were synthesized by a colloidal method to investigate the structural and electrochemical properties of various particle sizes. The samples were characterized by means of transmission electron microscopy (TEM), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), near-edge X-ray abs...
Three-dimensionally ordered macroporous (3DOM) materials are composed of well-interconnected pore and wall structures with wall thicknesses of a few tens of nanometers. These characteristics can be applied to enhance the rate performance of lithium-ion secondary batteries. 3DOM monoliths of hard carbon have been synthesized via a resorcinol-formald...
Upon lithiation, the active (Ga) and inactive component (Cu) in a binary intermetallic CuGa2 electrode are converted to nanograins ( Ga - Li). The Li.,Ga phase diagram is altered by the presence of Cu nanograins, eloquently demonstrating that the surface energy becomes more important than internal energy in controlling thermodynamics of nanosized m...
Spinel LiMn2O4 is a low-cost, environmentally friendly, and highly abundant material for Li-ion battery cathodes. Here, we report the hydrothermal synthesis of single-crystalline beta-MnO2 nanorods and their chemical conversion into free-standing single-crystalline LiMn2O4 nanorods using a simple solid-state reaction. The LiMn2O4 nanorods have an a...
Sorption isotherms of methane in Zn-2(bdc)(2)(dabco) are measured up to a pressure of 35 bar in the temperature range between 198-296 K. The methane sorption measurements at 296 K showed an uptake of 1.37 cm(3) cm(-3) at 35 bar. The enthalpy of methane adsorption for Zn-2(bdc)(2) (dabco) estimated by the virial equation is 13.6 kJ mol(-1) at zero c...
A nanoscale coating of a Si layer on the pore walls of SnO2 nanotubes (Si-coated SnO2) leads to very good electrochemical performance in coulombic efficiency, rate capability and capacity retention compared with untreated SnO2 nanotubes. / close / 51 / 45
Ordered LiNi0.5Mn1.5O4 was synthesized through a solid-state reaction. Even though the material has a particle size of 3-5 mu m, it shows very high rate capability and excellent capacity retention. The capacity is as high as approximate to 78 mAh/g at a 167C discharge rate. This high discharge rate performance is consistent with first-principles ca...
We report amorphous-Si nanowire shell anodes, supported by NiSix nanowire cores, by catalyst-free two-step SiH4 chemical vapor deposition, where the metallic core acts as a mechanical supporter and a kinetically unlimited charge supplier. We have achieved highly reversible capacitance of over 3000 mAh g(-1) even at a 2C rate, with stable cyclic ret...
Tetraethylenepentamine (TEPA) was incorporated into as-synthesized mesoporous silica MSU-1 with cheap sodium silicate as silica source to create TEPA/MSU-1, an adsorbent having high adsorption capacity for carbon dioxide. The adsorbents were characterized by X-ray diffraction (XRD), N-2 adsorption/desorption, thermogravimetry (TG), and Flourier tra...
We have explored new Li-polymer batteries composed of surface functionalized Si nanoparticles (SiNPs) as anode active materials and nanostructured block copolymers as solid electrolytes. Surface protection of SiNPs with poly(ethylene oxide) chains successfully prevents aggregation of SiNPs during cycling and also helps fast Li+ transport to the act...
