The experimental results showed that there was a significant influence of base agent nature on the morphology, structure, surface area of TiO2 product. Using NH3 agent could obtain uniform TiO2 particles with about 15 nm in size and surface area of m2 .g-1 , while using NaOH or KOH led to TiO2 with varying particle sizes (in the range of 15-500 nm), and decreasing surface area (less than 20 m2 .g-1 ). | Vietnam Journal of Chemistry, International Edition, 55(2): 227-230, 2017 DOI: Study on the influence of various base agents in K2TiF6 hydrolysis on morphology, structure and photocatalytic activity of TiO2 Nguyen Tan Lam1*, Nguyen Thi Dieu Cam1, Nguyen Phi Hung1, Nguyen Van Noi2 1 2 Quy Nhon University Hanoi University of Science, VNU - Hanoi Received 12 July 2016; Accepted for publication 11 April 2017 Abstract K2TiF6 was hydrolyzed by various base agents including solutions of NH3, NaOH, and KOH at the same concentration of 3 M. TiO2 material was obtained after filtering, washing, drying and calcination at 500 °C of Ti(OH)4 precipitate. The experimental results showed that there was a significant influence of base agent nature on the morphology, structure, surface area of TiO2 product. Using NH3 agent could obtain uniform TiO2 particles with about 15 nm in size and surface area of , while using NaOH or KOH led to TiO2 with varying particle sizes (in the range of 15-500 nm), and decreasing surface area (less than 20 ). The nature of base agent also significantly influenced photocatalytic activity of TiO2 product for methylene blue (MB) decomposition. The prepared TiO2 from NH3-using process showed the highest phtocatalytic activity in comparison with TiO2 from KOH/NaOH-using process or commercial TiO2 (P25). Keywords. K2TiF6, TiO2, Ti(OH)4, photocatalyst. 1. INTRODUCTION morphology, structure and photocatalytic activity of TiO2 Nanocrystalline titanium dioxide (NTO) is a multifunctional semiconductor photocatalyst. NTO can be used as a catalyst for energy (production hydrogen fuel from water splitting), or for environmental treatment (cleaning air and water), etc. Compared to other available photocatalysts, NTO has many advantages such as high chemical and photochemical durability, environmental friendliness, high activity for decomposition of pollutant organic compounds without any other oxidizers [1, .
