N. ‘Aliaa Razali and S. A. Othman, “Synthesis and Characterization of Nitrogen Doped with Titanium Dioxide at Different Calcination Temperature by using Sol-Gel Method”, jst, vol. 9, no. 3, Dec. 2017, Accessed: Aug. 12, 2026. [Online]. Available: https://journal.uthm.edu.my/index.php/JST/article/view/2158