there was difference in the crystal peaks but the superior crystallinity was represented in the specimens 1 2 3 and 4 prepared according to embodiments 1 to 4 all specimens had the anatase phase regardless of the carbon number in the carbon chain of the surfactant fig7 is a graph showing a test result of nitrogen adsorption and desorption for specimens prepared according to embodiments 1 to 3 of the present invention referring to fig7 the test result of nitrogen adsorption and desorption for the specimens 1 2 and 3 prepared according to embodiments 1 to 3 represented the curve of the typical nanopores and the specific surface area was increased as the carbon number in the carbon chain of the surfactant was reduced fig8 is a graph showing a test result of the organic matter photolysis for specimens prepared according to embodiments 1 to 4 of the present invention and comparative example 1 the organic matter photolysis test was performed after storing the specimens prepared according to embodiments 1 to 4 and comparative example 1 in a closed test tube for 40 hours together with reactive black 5 1 mg l and rohdamine b 0 1 g l referring to fig8 it can be understood from the test result of the organic matter photolysis that the specimens prepared according to embodiments 1 to 4 represented the superior purifying performance as compared with a specimen 5 prepared according to comparative example 1 in detail the specimens prepared according to embodiments 1 to 4 represented the superior purifying performance as compared with.