RHODAMINE B DEGRADATION BY PHOTOELECTROCATALYTIC SYSTEM USING La2O3 DOPED TiO2/Ti AND TiO2/Ti NANOTUBE AS A WORKING ELECTRODE

• Main Author: ARHAM (20513048), ZUL
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/24863
• Institution: Institut Teknologi Bandung

Dyes pollutions has become a seriuos problem to the environment for many years. Complexity and stability molecular structure of dyes on light exposure to waste treatment is difficult to develop. Moreover the existence of dyes is continually produced globaly. Some techniques of dyes waste treatment have been developed, but the available method developed is not effective to over come the presence of dyes in wastewater. In the recent years photocatalytic oxidation method has been proved effective to reduce dyes in waste water and become main priority in development of this method. Titanium dioxide (TiO2) is a semiconductor material that has many application to degrade photocatalytically. This is because TiO2 has environmental friendly characteristic, non toxic, low operational cost, good physical and chemical caracteristic, and high photocatalytic activity. Some <br /> <br /> <br /> <br /> <br /> <br /> disadvantages of TiO2 powder usage as photocatalytic material, encourage scientist to keep doing modification of that material. The method developed recently is a doping method either metals or non metals. These two methods have been proved effective to fix characteristic of TiO2 photocatalytic and improving its degradation activity. This research develops a doping method and photoelectrocatalytic to degradate rhodamine B as a model of dyes based on electrochemical system. Fabrication of TiO2/Ti working electrode was done by electrochemical method. TiO2/Ti working electrode fabricated has been studied its electrochemical characteristic in the mixed solution of K3[Fe(CN)6] and K4[Fe(CN)6], and in rhodamine B solution by using cyclic voltammetry technique. From that characterization known that, TiO2/Ti was quasi irreversible and for electrochemical was controled by difussion rate, while in the rhodamine B v solution was known that its oxidation potensial is 1,54 V. XRD, FTIR, UV-Vis DRS, SEM-EDX analysis were used for characterization of crystal structure, function group, band gap energy, and photocatalytic morphology of TiO2/Ti and La2O3 doped TiO2/Ti electrodes. Result of the analysis showed that TiO2 crystal structure is anatase, and the presence of lanthanum oxide unchanges the TiO2 crystal structure but shift TiO2 working area was changed to visible light area. Degradation activity of TiO2/Ti and La2O3 doped TiO2/Ti were applied in the photoelectrocatalytic reactor by illuminating UV light for 100 minutes by using two electrode systems and 0.1 M NaCl pH 4 as supporting electrolyte. Degradation activities were compared with photodegradation, electrochemical, <br /> <br /> <br /> <br /> <br /> and photocatalytic methods. From those comparison either TiO2/Ti working electrode or La2O3 doped TiO2/Ti were explained that photoelectrocatalytic method has the best degradation activity with efficiency degradation 45.42% for TiO2/Ti and 98.04% for La2O3 doped TiO2/Ti. Based on the results were proved that lanthanum oxide doping on the surface of TiO2/Ti could improve photocatalys TiO2 efficiency degradation. The Study of TiO2/Ti and La2O3 doped TiO2/Ti photoeletrocatalytic degradation kinetic were determined by using pseudo-kinetic. The result of kinetic’study was known that rhodamine B photoelectrocatalytic degradation to both working electrode followed firts order pseudo-kinetic.