Nguyen, Cam, and Tung Mai. “Preparation of N-TiO2 Nanomaterial and Evaluation of Its Photocatalytic Activity under Visible Light”. VNUHCM Journal of Natural Sciences 1, no. T4 (December 31, 2017): 27-35. Accessed October 4, 2025. http://stdjns.scienceandtechnology.com.vn/index.php/stdjns/article/view/493.