Abstract: There is provided a method for preparing an anatase type titanium dioxide photocatalyst having a particle size of nano level without a need of the sintering process at high temperature, and an anatase type titanium dioxide photocatalyst having a particle size nano level. The method for preparing an anatase type titanium dioxide photocatalyst having a particle size of nano level includes adding a titanium-based starting material to a selected solvent and adding an acid or base catalyst to the resulting aqueous solution. Next, subjecting the catalyst-containing aqueous solution to heat treatment at about 80±20° C. to activate peptization thereby preparing an anatase type titanium dioxide sol solution. Finally, the anatase type titanium dioxide sol solution is coated onto a support to complete the preparation of the photocatalyst.

Abstract: A gas sensor and a method for fabricating the same includes a semiconductor substrate, a supporting layer formed on the semiconductor substrate, the supporting layer being electrically insulative and having a pattern groove formed therein, a heater formed in the pattern groove, an electrically insulating layer formed on the heater and the supporting layer, an electrode formed on the insulating layer, and a sensing layer formed on the electrode and the insulating layer to detect a target gas of interest according to a measured change in electrical conductivity or resistance thereof.

Abstract: Air pollution gas sensor which efficiently detects smell from smoking, ordinary stinks such as TMA and CH3SH, smell of Kimchi, acetaldehyde, and etc. and also a method for fabricating the same is revealed and described including a substrate, a heater formed on said substrate, electrodes each formed on said substrate insulated from the heater, and a sensing layer formed of SnO.sub.2, including WO.sub.3 on said substrate including said electrodes, with the method for fabricating the gas sensor including the steps of forming the heater on the substrate, forming the electrodes on the substrate insulated from the heater, and forming a sensing layer of SnO.sub.2 including WO.sub.3 on the substrate including the electrodes.