A series of nanometer TiO_2 photocatalysts doped respectively by elements with atomic number from 23 to 30 were prepared. Their photocatalytic activities in photodegradation of sodium dodecyl benzene sulfonate were measured. The relationships between the activities and microcrystallite structure of the catalysts, the ratio of electronic affinity to ionic radius of doped atom and ionic magnetic moment of doped atom were studied. It is found that the catalytic activity correlats well with the ratio and magnetic moment. The X-ray diffraction intensity, microcrystallite size, and micro- strain of (101) crystal face of the catalysts had a certain influence on the catalytic activity.

Key words: TITANIUM DIOXIDE, DOPE, PHOTOCATALYSIS, ALKYLBENZENESULFONIC ACID, CATALYTIC ACTIVITY