Luận văn thạc sĩ fabrication of photocatalytic thin films containing tio2 nanoparticles and poly(l

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THAI NGUYEN UNIVERSITY

UNIVERSITY OF AGRICULTURE AND FORESTRY

DUONG CUONG THINH

FABRICATION OF PHOTOCATALYTIC THIN FILMS CONTAINING

TIO2 NANOPARTICLES AND POLY(L-DOPA) BY LAYER-BY-LAYER

SELF-ASSEMBLY

BACHELOR THESIS

Study

Mode

: Full- time

Major : Bachelor in Environmental Science and

Management

Faculty : International Training and Development Center

Batch : 2011-1016

Thai Nguyen, 15/09/2016

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DOCUMENTATION PAGE WITH ABSTRACT

Thai Nguyen University of Agriculture and Forestry

Degree Program Bachelor in Environmental Science and

Management

Student Name Duong Cuong Thinh

Student ID DTN1153180221

Supervisor Assoc. Prof. Wu Chien-Hou

PhD. Nguyen HuuTho

Abstract: The photocatalytic thin films containing TiO2 nanoparticles and poly(L￾Dopa) were fabricated by layer-by-layer self-assembly. The thin films were

characterized by dynamic light scattering (DLS), Fourier transform infrared

spectroscopy (FTIR), scanning electron microscopy (SEM), and atomic force

microscopy (AFM). The photocatalytic activity was evaluated through the degradation

of sulforhodamine B (SRB) in aqueous solution. Nano-structured thin films under

different conditions and their photocatalytic activities were investigated and studied.

Poly(acrylic acid) (PAA) was used to verify the role of poly(L-Dopa).The results show

that layer-by-layer self-assembly was a simple and useful method to fabricate Nano￾structured thin films with low cost and high reusability. High transparency films using

Degussa P25 was attributed to suitable particle size and colloidal stability. Poly(L￾Dopa) with negatively charge at wide range of pH values made it a good substitute

among commercially available polyelectrolytes. P25 and poly(L-Dopa) were recorded

as an optimal charge with high zeta-potential and small particle size, contributing for

high colloidal stability and low sedimentation at pH 3. The obtained multilayer films

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retained the band gap of bare P25 at 3.2 eV and the properties of functional groups of

poly(L-Dopa). The optimal number of P25/Poly(L-Dopa) bilayers was 20.5.The

photocatalytic thin films containing P25 and poly(L-Dopa) are promising materials for

environmental remediation.

Keywords:Titanium dioxide, layer-by-layer self-assembly, P25, poly(L-Dopa)

Number of page 51

Date of Submission 15/09/2016

Supervisor’s signature

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ACKNOWLEDGEMENT

To have completed this thesis, in addition to the ongoing efforts of myself, I

would like to thank for teachers in faculty of International Training and Development

as well as teachers in Thai Nguyen University of Agriculture and Forestry, who have

dedicated teaching to me the valuable knowledge during study time in the university

and given me a chance to do my thesis oversea. I had a precious opportunity to take

part in the internship in Department of Biomedical Engineering and Environmental

Sciences in National Tsing Hua University (NTHU), Taiwan.

First of all, I want to thank my supervisors Assoc. Prof. Wu Chien-Hou from

Biomedical Engineering & Environmental Science Department, National Tsing Hua

University and PhD. Nguyen Huu Tho from Thai Nguyen University of Agriculture

and Forestry. Their priceless advices are not only valuable to my research in order to

gain successful results, but also contribute to my future career orientation.

Secondly, I am grateful to Mr. Weichang Yuan, MS student and my friends in

the laboratory, who facilitated and provided the information and data necessary for my

implementation process and helped me finish this thesis.

Last but not least, thanks to my parents and good friends who always encourage

me and offer support and love.

Sincerely,

Duong CuongThinh

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TABLE OF CONTENT

ACKNOWLEDGEMENT............................................................................................. iii

TABLE OF CONTENT .................................................................................................iv

LIST OF FIGURES.........................................................................................................1

LIST OF TABLES ..........................................................................................................3

LIST OF ABBREVIATIONS .........................................................................................4

PART I. INTRODUCTION ............................................................................................5

1.1. Research rationale ..............................................................................................5

1.2. Research’s objectives.........................................................................................7

1.3. Research questions and hypotheses...................................................................7

1.4. Limitations.........................................................................................................7

PART II. LITERATURE REVIEW................................................................................8

2.1. Overview of Titanium dioxide..............................................................................8

2.1.1. Titanium oxidation structures and properties.................................................8

2.1.2. The photocatalytic activity of TiO2 ................................................................9

2.2. Layer-by-layer self-assembly..............................................................................10

2.3. Overview of Poly(L-Dopa) .................................................................................12

PART III. METHODS...................................................................................................13

3.1 Material ................................................................................................................13

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