Eiji Hosono

How to improve the specific power density of the rechargeable lithium ion battery has recently become one of the most attractive topics of both scientific and industrial interests. The spinel LiMn2O4 is the most promising candidate as a cathode material because of its low cost and nontoxicity compared with commercial LiCoO2. Moreover, nanostructured electrodes have been widely investigated to satisfy such industrial needs. However, the high-temperature sintering process, which is necessary for h

We first fabricated the superhydrophobic film with a water contact angle of 178 degrees based on a perpendicular nanopin fractal structure by a bottom-up process. Until now, only materials with an original water contact angle larger than 90 degrees , which is classified as hydrophobicity, could be used to fabricate the superhydrophobic film (>170 degrees ) according to the possible fractal structure by a top-down process. Now, in this work, a water contact angle of about 178 degrees can be achie

Evolution of a new morphology of rutile TiO2 films consisting of nearly single-crystalline parallelepipeds was achieved through hydrothermal treatments of aqueous TiCl3 solutions in the presence of NaCl.

Upright-standing nanocrystalline ZnO films, with the c-axis parallel to the substrate, are fabricated by the pyrolysis of films made of upright-standing sheets of layered hydroxide zinc carbonate (LHZC) (see Figure). Dye-sensitized solar cells (DSCs) prepared using the ZnO films possess the highest level of conversion efficiency for 1.5 AM illumination in ZnO DSCs due to the specific morphology of the ZnO electrode.

Films of brucite-type cobalt hydroxide with nanorod morphology and hydrotalcite-type cobalt hydroxide with nanosheet morphology films were fabricated by heterogeneous nucleation in a chemical bath using water and a mixed solution of water–methanol as solvents, respectively. Since oxygen is around 25 times more soluble in methanol than in water, a methanol solution was used to convert a part of divalent cobalt ions into trivalent cobalt ions through oxidation, due to the amount of dissolved oxyge

A triaxial LiFePO4 nanowire with a multi wall carbon nanotube (VGCF:Vapor-grown carbon fiber) core column and an outer shell of amorphous carbon was successfully synthesized through the electrospinning method. The carbon nanotube core oriented in the direction of the wire played an important role in the conduction of electrons during the charge-discharge process, whereas the outer amorphous carbon shell suppressed the oxidation of Fe2+. An electrode with uniformly dispersed carbon and active mat

A method was developed for preparing perpendicular TiO2 nanosheet films from titanate nanosheet films produced on a titanium metal sheet by hydrothermal treatment with aqueous urea. The method is based on the consideration of some important points relating to the thermodynamics of nucleation and crystal growth. The resulting anatase TiO2 nanosheet films showed a specific superhydrophilicity without the need for any prior UV irradiation.

The solution synthesis of large single crystals of octahedron-like anatase TiO2 is reported, although this novel result is unexpected in the light of reported theoretical calculations. Moreover, systematic control of the crystal growth of rutile nanopins on the microanatase octahedron single crystal results in a nano-micro chestnut-like TiO2 structure. The control of the formation of rutile nanopins on the large single crystals of anatase in the same solution is an interesting and useful techniq

Structural and morphological control is an effective approach for improvement of electrochemical properties in rechargeable batteries. One-dimensionally assembled structure composed of NASICON-type Na3 V2 (PO4 )3 nanoparticles were fabricated through an electrospinning method to meet the requirements for the development of efficient electrode materials in Na-ion batteries. High-temperature treatment of electrospun precursor fibers under an argon flow provides a nonwoven fabric of nanowires compr