HYDROTHERMAL SYNTHESIS OF NANOSTRUCTURED TIO2 PARTICLES IN AN ALKALI CONDITION DECORATED TRANSITION METAL OXIDE CLUSTER (MN, CO, NI)

• Main Author: Voni Steky, Fry
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/57350
• Institution: Institut Teknologi Bandung

TiO2 is well-known as a photocatalyst due to its superior performance in photodegradation, stability, corrosion resistance, low production cost, and environmentally friendly. However, the TiO2-based photocatalyst system has weaknesses, i.e., low absorption coefficient in visible light, low surface area, and fast recombination rate between holes and electrons. These drawbacks can be overcome by using TiO2 particles with bicontinuous concentric lamellar (bcl) morphology and decorating the particles with transition metal oxide clusters. Transition metals such as Mn, Co and Ni have been featured in enhancing TiO2’s ability to utilize visible light. The hydrothermal synthesis of TiO2 nanostructured particles with bcl morphology was carried out under alkaline conditions at 120 ° C for 6 hours. These particles were modified with transition metal oxide clusters (Mn, Co, Ni) by dispersing the particles into transition metal salt solutions, then heated at 120 ° C for 6 hours. Then the particles were calcined at 500 ° C for 1 hour. The synthesized particles were characterized using SEM, XRF, Raman spectroscopy, XRD and UV-Vis. Based on the results of SEM characterization, it appears that the synthesized particles have bcl morphology with an average particle size of about 2.5 µm. The presence of metal oxide clusters (Mn, Co, Ni) was observed from the results of XRF characterization, with the most dominant metal content of Mn, Co, and Ni being 10.15%, 6.06%, and 7.87%, respectively. Raman and XRD spectroscopic characterization results showed that the TiO2 particles synthesized had a crystalline structure with anatase polymorphs. Further analysis showed that the presence of metal oxide clusters did not significantly affect the crystallinity and structure of the particles. However, the presence of metal oxide clusters increased the absorption in visible light, as indicated by the UV-Vis characterization results. Based on the analysis of the characterization results, synthesized nanostructured TiO2 particles with bcl morphology are decorated with metal oxides (Mn, Co, Ni), providing better absorption in the visible range than the conventional TiO2 nanoparticles.