Tokyo Institute of Technology

Masahiro Yoshimura

Tomoaki Watanabe

Seung-wan Song

Takeshi Fujiwara

Kyoo-Seung Han

Ryo Teranishi

A reactive solution with an amount of 250 mL is made of distilled water and LiOH&middot;H O (4M) melted in the distilled water. Then, the reactive solution is put in a flow-type reactor, and is flown in between an anode electrode and a cathode electrode set in the flow-type reactor at a given temperature and a given flow rate. Then, a given voltage is applied between the anode electrode and the cathode electrode with dropping an oxidizer of hydrogen peroxide (H O ) into the reactive solution to form a lithium-cobalt oxide thin film on the anode electrode.

Method for forming a thin film

A water solution of lead nitrate is infiltrated into a substrate made of a porous material, and liquid drops of a water solution of sodium sulfide, which is charged into a ink cartridge of a minute nozzle, are sprayed onto the substrate from the minute nozzle. The lead component from the lead nitrate water solution and the sulfur component from the sodium sulfide water solution are synthesized directly on the substrate, and thus, a thin film made of lead sulfide is formed on the substrate.

A blended solution is made by melting LiOH.H O into distilled water, and then, Co metallic powders are added into the blended solution to make a reactive solution. The reactive solution is charged into an autoclave, and held at a predetermined temperature. Then, a pair of platinum electrodes are set into the reactive solution, and a given voltage is applied between the pair of platinum electrode. As a result, a compound thin film, made of crystal LiCoO including Li element of the blended solution and Co element of the Co metallic powders, is synthesized on the platinum electrode constituting the anode electrode.

A first reactive solution is made of a water solution composed of LiOH.7H O melted in distilled water, and a second reactive solution is made of a water solution composed of CoSO .7H O melted in distilled water. Then, the first and the second reactive solutions are put in a flow-type reactor with a pair of electrodes and a porous base material provided in between the pair of electrodes therein. The first reactive solution is flown in between one electrode and the porous base material at its given flow rate, and the second reactive solution is flown in between the other electrode and the porous base material at its given flow rate. Then, a given voltage is applied between the pair of electrodes to synthesize a compound thin film including the components of the first and the second reactive solutions directly on the porous base material.

In the formation of a double oxide film of Li element and a metal element other than Li element, a metal body of the metal element selected from the group consisting of Ni, Co, V, Fe, Cr and Al is immersed in an alkaline solution containing Li ion to conduct a hydrothermal reaction between the metal body and Li ion, whereby a double oxide film is formed on the surface of the metal body.

Growing community of inventors

Kanagawa Pref., Japan

Masahiro Yoshimura