Anatase TiO(2) nanosheets with highly reactive (001) facets exposed have been successfully synthesized by a facile hydrothermal route, taking advantage of a specific stabilization effect of fluorine ion on (001) facets. The percentage of highly reactive (001) facets in such TiO(2) nanosheets is very high (up to 89%). In addition, the as-prepared TiO(2) nanosheets exhibit excellent activity in the photocatalytic degradation of organic contaminants.