THAI NGUYEN UNIVERSITY THAI NGUYEN UNIVERSITY OF AGRICULTURE AND FORESTRY -------------- NGUYEN THUY GIANG TOPIC TITLE: PHOTOCATALYTIC DEGRADATION OF METHYL ORANGE USING FERRITE DOPED TITANIUM DIOXIDE BACHELOR THESIS Study Mode: Full-time Major : Environmental Science and Management Faculty : International Training and Development Center Batch : 2011 - 2015 Thai Nguyen, 30/09/2015 n THAI NGUYEN UNIVERSITY THAI NGUYEN UNIVERSITY OF AGRICULTURE AND FORESTRY -------------- NGUYEN THUY GIANG TOPIC TITLE: PHOTOCATALYTIC DEGRADATION OF METHYL ORANGE USING FERRITE DOPED TITANIUM DIOXIDE BACHELOR THESIS Study Mode: Full-time Major : Environmental Science and Management Class : K43 – AEP Faculty : International Training and Development Center Batch : 2011 – 2015 Advisor Advisor Prof. Ruey-An Doong Assoc. Nguyen The Hung Department of Biomedical Department of Environment Engineering and Environmental Thai Nguyen University of Sciences Agriculture and Forestry, Vietnam National Tsing Hua University, Hsinchu, 30013, Taiwan n DOCUMENTATION PAGE WITH ABSTRACT Thai Nguyen University of Agriculture and Forestry Degree program Bachelor of Environmental Science and Management Student name Nguyen Thuy Giang Student ID DTN1153070022 Thesis Title Photocatalytic degradation of Methyl Orange using ferrite doped titanium dioxide Supervisor (s) Prof. Ruey-An Doong and Assoc.
Nguyen The Hung Abstract: Titanium dioxide (TiO2) has high potential to split water into hydrogen and oxygen, and the development of semiconductor photocatalysis using for a wide range of environmental applications. Therefore, one of the most significant scientific advance has been the development of visible light active TiO 2 photocatalytic materials. In this study, a method of synthesis copper ferrite doped titanium dioxide (P25@CuFe2O4) was conducted to enhance the ability of TiO2 using visible light. CuFe2O4 and P25@CuFe2O4 were synthesized by hydrothermal process.
The composite structure and the presence of the copper ferrite and titanium dioxide phase have been confirmed by TEM, XRD and UV- vis spectroscopy. P25@CuFe2O4 show good magnetic property, which can get under an external applied magnetic field. Photocatalytic ability was examined by degrading methyl orange dye. The synthesized P25@CuFe2O4 display the potential of TiO2 photocatalyst under visible irradiation and find the recoverable potential applications in cleaning water pollution with the high magnetic property.
ii n Keywords Copper ferrite, degradation, photocatalyst, titanium dioxide, visible light Number of pages 43 Date of submission 30/09/2015 iii n ACKNOWLEDGEMENT With deep sense of gratitude, I would like to express my sincere thanks to all those who gave me the possibility to complete thesis work. First and foremost, I would like to express my sincere gratitude to my supervisor Prof. Ruey-An Doong of National Tsing Hua University, Taiwan, who guided and motivated me to complete my research. I would also like to express my thanks to Assoc.
Nguyen The Hung, the second supervisor, for his support, encouragement throughout my thesis. Besides my supervisors, I would like to thank PhD. Nguyen Thanh Binh for his valuable, assistant, advices during all my experiments, analysis and writing thesis time. I would like to thank PhD.
Rama Shanker Sahu and Duncan for preparing and characterizing my samples. I would also like to thank and all FATECOL members who work in Biomedical Engineering and Environmental Sciences, National Tsing-Hua University, Taiwan, who provided their support, guild and suggestions. My sincere thanks also go to Ngoc Anh and Dai for helping me to the end of this study. Finally, I would like to express my special thanks and gratitude to my beloved parents, my friends for their love and encourage throughout all the time.
Thai Nguyen, 30th September, 2015 Student Nguyen Thuy Giang iv n TABLE OF CONTENTS LIST OF FIGURES .1 LIST OF TABLES .3 LIST OF ABBREVIATIONS .1 Nanotechnology and Nanomaterial .2 Nanocatalysis and Photocatalysis .3 Copper ferrite doped P25 Titanium dioxide .4 Copper ferrite doped P25 Titanium dioxide (P25@CuFe2O4) .1 Transmission Electron Microscopy .3 UV – Visible spectroscopy.1 Synthesis of copper ferrite nanoparticles .2 Synthesis of copper ferrite doped P25 titanium dioxide .3 Method of characteristic and morphological measurement .1 Transmission Electron Microscopy .2 Uv-visible spectroscopy .4 Photocatalytic activity testing. RESULTS AND DISCUSSION .1 Characterization and morphology of CuFe2O4 and P25@CuFe2O4 .3 Assessing the ability of methyl orange degradation. CONCLUSION AND RECOMMENDATION .42 vi n LIST OF FIGURES Figure 2.1 Expected benefits of nanocatalysis .2 Comparison of different electronic band structures of metal, semiconductor and insulator .3 Schematic of TiO2 photocatalytic mechanism .4 Separation of magnetic nanoparticles using an external magnet (Geukens, 2013) .1 Preparation of Copper ferrite nanoparticles.2 The sample of copper ferrite powder .3 Preparation of Copper ferrite doped P25 Titanium dioxide .4 The sample of P25@CuFe2O4 powder.5 Schematic of major components for image creation of a typical transmission electron microscopy (TEM) .6 A schematic of a double-beam spectrophotometer .8 The resultants of methyl orange after degradation time by using P25@CuFe2O4 with under UV irradiation light (a), visible light (b).9 Standard line for calculation the degradation of methyl orange .1 TEM image of P25@CuFe2O4 powders .2 XRD pattern of CuFe2O4, P25 TiO2 and P25@CuFe2O4 .3 Separation of CuFe2O4 (a,b) and P25@CuFe2O4 (c,d) by using external magnet in hexane.4 UV-vis reflection spectra for the samples of P25, CuFe 2O4 and P25@CuFe2O4 .5 The effect of P25@CuFe2O4 on the degradation of methyl orange under UV light irradiation (λ = 305 nm) .6 The effect of P25@CuFe2O4 on the degradation of methyl orange under visible light irradiation (λ = 465 nm) .38 2 n LIST OF TABLES Table 2.1 Physical and structural properties of anatase and rutile TiO 2. 14 3 n LIST OF ABBREVIATIONS CB : Conduction band CuFe2O4 : Copper ferrite DI : Deionized MO : Methyl Orange NPs : Nanoparticles P25 : Titanium dioxide contains the 80% of Anatase and 20% of Rutile morphology P25@CuFe2O4 : Copper ferrite doped P25 Titanium dioxide UV-vis : Ultraviolet-visible TEM : Transmission Electron Microscopy VB : Valence band XRD : X-Ray Diffraction 4 n PART I.1 Research rationale Nowadays, chemical industry plays a vital role in our modern technological society by supplying us with energy, medicines, foodstuffs, and new materials worldwide.
Unfortunately, even though chemistry is the science with the highest impact on our everyday lives, chemicals and the chemical industry have a poor public image. In the end of 20th century, the traditional chemical industry was considered as a hazardous and polluting one due to generating stoichiometric amounts of waste, causing much pollution of both air and water. The mostly serious chemical accident was the Bhopal disaster in 1984 with 3000 people were died and more than 40,000 were injured by the methane gas (Rothenberg, 2008). Changing traditional chemical industry is one-step along the road to sustainability.
In fact, sustainable process is one that optimizes the use of resources, while still leaving sufficient resources for future generations. As far as chemistry is concerned, photocatalysis is the key to sustainability. In addition, the most popular in photocatalysis scale is titanium dioxide NPs (TiO2). TiO2 is very powerful in decomposition of organic compounds and production of H2 as a fuel using solar energy.
Wu et al. (2011) reported that TiO2 possesses many advantages such as low cost, high surface area, nontoxicity, high chemical stability, and effective removal for organic pollutants. Besides, 5 n TiO2 also support to ease the energy crisis through effective utilization of solar energy based on photovoltaic and water-splitting devices (Wu et al. However, there are two disadvantages with TiO2 such as high charge recombination and low efficiency for using solar light.
Moreover, the overuse and abuse of photocatalyst without recycling will lead the environment to pollute. To enhance the utilization of visible light and the separation situation of charge carriers, one of the most useful method is ferrite doping. Base on some rationales above; I conducted a research “Photocatalytic degradation of methyl orange using ferrite doped titanium dioxide”.2 Research’s objective The main objective of this study is to enhance the ability of using visible light of TiO2 as a photocatalyst through successful synthesis of P25@CuFe2O4 and using it to degrade methyl orange. To specific, copper ferrite (CuFe2O4) and copper ferrite doped titanium dioxide (P25@CuFe2O4) were synthesized by hydrothermal method.
Characteristic and morphology of materials were analyzed by TEM, XRD and Uv-vis spectroscopy. Therefore, performing the degradation experiments on methyl orange will identify these properties and evaluate the efficiency for utilizing solar light.3 Research question - Could the synthesis of ferrite doped titanium dioxide be success by hydrothermal method? 6 n - What is the characterization and morphology of ferrite doped titanium dioxide? Is it suitable to use as a catalyst for degradation of methyl orange? - How is the efficiency of photocatalytic degradation process? 1.4 Limitations Because the research time is limited, the study cannot include all the analysis to have an exact assessment of the chemical and physical characterization of ferrite and ferrite doped titanium dioxide.1 Nanotechnology and Nanomaterial 2.2 Nanomaterial To synthesis nanomaterial, there are two approaches: top-down and bottom-up. - Top-down approach refers to successive cutting of a bulk material to get nano-size particle. It includes some experimental methods such as attrition or milling, etching, vapour phase condensation, sputtering, electro-explosion and laser ablation.
Top-down approach has problem with imperfection of the surface structure. The conventional top-down techniques such as lithography can cause significant crystallographic damage. However, the top-down approaches play an important role in the synthesis and fabrication of nanostructures for their economy and mass scale production. - Bottom-up approach refers to form a material from a component at the level of atoms or ions to nanoparticles.
For example of bottom-up approach, it includes colloidal dispersion, nanolithography and nano manipulation, micro- emulsion, sol-gel, reverse micelle and chemical co-precipitation. Bottom-up 8 n approach promises a better chance to obtain nanostructures with less defects, more homogeneous chemical composition, and better short and long range ordering than top-down approach. - Co-precipitation is the process that I chose to use to synthesis copper ferrite and copper ferrite doped titanium dioxide in this research because of some reasons. Co-precipitation is the process in which precipitate of substances normally soluble under the room conditions.
Besides, Co-precipitation is used as a method of magnetic nanoparticles synthesis. In recent years, co-precipitation approach has been used extensively to produce ferrite nanoparticles of controlled sizes and magnetic properties (Ayyappan et al.2 Nanocatalysis and Photocatalysis 2.1 Nanocatalysis Nanocatalysis is a rapidly growing field, which involves the use of nanomaterials as catalysts for a variety of catalytic reactions. Nanoparticles of metals, semiconductors, oxides, and other compounds have been widely used for important chemical reactions (Serp, 2013). Serp and Phillippot (2013) affirmed that catalysts could apply in a variety of industry segments spanning refinery, petrochemical, pharmaceuticals, chemical, food processing sectors and others.
An assessment of the global catalysts’ market reveals the following: - The global market for NPs used in catalytic applications increased from US $193.74 million in 2006 to an estimated US $200. 9 n It is expected to reach US $325 million by 2012, corresponding to a growth of 9.5% in the preceding five years, from 2007 onwards. - Commercially well-established catalysts such as industrial enzymes, zeolites and transition metal catalysts, till recently, accounted for about 98% of global sales. - However, nanocatalysts, such as transition metal oxides, gold catalysts, carbon nanotubes and others are expected to more than triple their combined market share from 2009 onwards.
- It is the smaller end-user segments whose consumption is growing the fastest. Improved economy Minimum Energy chemical efficiency waste Nanocatalysis Safer Reduced global catalyst warming & reagent Optimum Waste- feedstock water utilization treatment Figure 2.1 Expected benefits of nanocatalysis (Serp and Phillippot, 2013) 10 n 2.2 Photocatalysis Mul (2012) found that light of high enough energy can be used without any catalyst to activate chemical bonds, which is the field of photochemistry, also referred to as photolysis. Photocatalysis is the use of a photon-excited catalyst to accelerate a thermal reaction, in which the catalyst should not undergo a permanent transition, but be restored to its initial configuration. When a photocatalyst absorbs UV/Vis light energy, a transition in the electronic state occurs, yielding the photo-excited state.