第四章 結果與討論
4.3 光催化實驗
4.3.5 光催化過程中改變結晶紫溶液的 pH 值
藉由改變結晶紫溶液 pH 值測詴溶液酸鹼性對降解效率的影響，結晶 紫溶液 pH 值分別有 4、6.5、10，觸媒則是 Bi7O9I3跟 Bi7O9I3/ GO (pH=7, 0.05 克 GO)，圖 4.87 可以看出在 pH 值=4 時，吸附作用影響較小，在 pH 值=7、
10 時，有較大吸附作用，可以看出 Bi7O9I3在酸性下吸附較小，在鹼性下 可以明顯看到濃度逐漸上升又下降，代表先吸附後脫附，證明在鹼性下吸 附作用大。Bi7O9I3/ GO 在酸鹼性下均比 Bi7O9I3有較佳吸附能力跟降解效 率，加入 GO 使其在酸性條件下有較佳吸附作用，是因為 GO 帶有負電，
因此在鹼性時，兩者吸附作用相近，
圖 4.87 Bi7O9I3跟 Bi7O9I3/ GO (pH=7, 0.05 克 GO) 光降解不同 pH 值 10ppm 結晶紫染料之降解效率圖
4.3.6 結晶紫染料光催化過程中間產物之分析
在圖 4.88 中為 BiOxIy/ GO 進行光催化反應機制示意圖，BiOxIy照射可 見光後，將電子從價帶激發至導帶，有些電子被導至 GO 上，與 O2反應 形成〃O2-，將電子導至 GO 上能降低電子電洞重組率，價帶則產生電洞氧 化 OH- 形成〃OH，進而與結晶紫染料進行降解反應，而結晶紫也會吸收 光能，進行光敏化反應，但反應不是主要影響將解因素。圖 4.89 中為 BiOxIy/
g-C3N4異質結合進行光催化反應機制示意圖，可以看到 BiOxIy跟 g-C3N4 照射可見光，將電子從價帶激發至導帶，而 BiOxIy會將電動轉移至 g-C3N4， g-C3N4會將電子轉移至 BiOxIy，使電子電洞分離兩邊，降低重組率，會有 更好的光催化效果。
圖 4.89
Bi7O9I3/g
-C3N4之反應機制示意圖4.3.7 結晶紫染料光催化過程中間產物之分析
圖 4.91 為光降解 CV 之 HPLC 分析圖，隨時間變化原本結晶紫 A 濃 度逐漸下降，產生其他較小分子，而我們將過程產物分為三類〆A-I、a-f、
α-γ，A-I 是逐漸被去烷基化的分子，從表 4.33 可以看出 A(372.4m/z)跟
B(358.5 m/z)相差了 14 m/z，為去除一個甲基(-CH3)並接上-H，以此類推至 I，而 a 跟 α 則是 A 被拆解成雙苯環結構跟單苯環結構之分子，A 跟 a 相差 103 m/z，為去除一個-C6H4N(CH3)2並接上一個-O，α 則是 C6H4N(CH3)2接 上-OH，a-f、α-γ 都為去甲基化過程【75-76】。圖 4.89 可以看到 A 系列主 要波段位於 580nm，a 系列主要波段位於 350nm，α 系列主要波段位於 300nm，
由此可知 CV 染料結構確實降解成較小分子，表 4.33 詳細記錄各分子之吸 收波段及質量。
圖 4.90 光降解 CV 染料之中間產物以 HPLC 分析，(a)580nm,(b)350nm.
(c)300nm.
圖 4.91 光降解 CV 染料之中間產物隨時間變化之 HPLC 分析，(a)580nm,(b)
350nm, (c) 300nm.表 4. 33 HPLC-PDA-MS 分析 CV 染料光降解之中間產物總表 HPLC
peaks De-methylation intermediates ESI/MS molecular ions (m/z)
Adsorption maximum (nm)
A N, N, N', N′, N", N"-hexamethyl-pararosaniline
372.4 588.2B N, N-dimethyl-N', N'-dimethyl-N"-methyl-pararosaniline
358.5 580.9C N, N-dimethyl-N′-methyl-N"-methyl-pararosaniline
344.4 574.2D N, N-dimethyl-N′, N′-dimethyl-pararosaniline
344.4 581.0E N-methyl-N′-methyl-N"-methyl-pararosaniline
330.4 566.5F N, N-dimethyl-N′-methyl-pararosaniline
330.2 570.4G N-methyl-N′-methyl-pararosaniline
316.4 562.9H N, N-dimethyl-pararosaniline
316.3 566.3I N-methyl-pararosaniline
302.3 555.3a
4-(N,N-dimethylamino)-4'-(N',N'-dimethylamino)benzophenone 269.3 377.2b
4-(N, N-dimethylamino)-4'-(N'-methylamino)benzophenone 255.2 366.5c
4-(N-methylamino)-4'-(N'-methylamino)benzophenone 241.1 362.8d
4-(N, N-dimethylamino)-4'-aminobenzophenone 241.2 359.7e
4-(N-methylamino)-4'-aminobenzophenone 227.1 357.1f
4,4'-bis-aminobenzophenone 213.3 339.0α
4-(N, N-dimethylamino)phenol 138.2 309.1β
4-(N-methylamino)phenol 121.1 289.9γ
4-aminophenol 111.0 278.34.4 實驗分析總整理
表 4.35
BiOxIy/GO 之降解速率常數總表表 4.36
BiOxIy/g-C3N4之 XRD 總表(◆代表 BiOI、●Bi7O9I3、▲代表Bismuth oxyiodide/g-C
3N
4Bismuth
第五章 結論與建議
件下，可以發現是第四型 H3，因此確定複合後確實能提升表面積。
7. BiOxIy/GO 跟 BiOxIy/ g-C3N4光觸媒在進行多次回收後，仍有良好光催 化效果，因此代表光催化效果不易衰變，可重複再利用。
8. 藉由 HPLC-PDA-ESI-MS，本研究可以成功鑑定對 CV 染料降解所產 生的中間產物及其降解機制，可以由此推演同類型染料之降解機制。
5.2 未來方向與建議
1. 可以利用二元鹵氧化鉍或其它氧化鉍相關光觸媒來複合 GO 或 g-C3N4， 相信會有良好的光催化活性。
2. 在複合方法中有沉澱法、化學還原法、光還原法等方法，之後可以嘗 詴其他方法，並探討其降解效果。
3. 可以利用可見光觸媒降解其他環境有機汙染物(如〆農藥、抗生素等)。
4. 現今有許多複合材料，如〆奈米碳管、二氧化碳奈米管、g-BN…等，
可嘗詴複合後之降解效果。
參考文獻
【1】
S. Norman. A Color Chemistry: Synthesis, Properties and Applications of Organic Dyes and Pigments (2nd Edition) : By H. Zollinger, published by VCH, Cambridge. Journal of Photochemistry and Photobiology A-chemistry, 1992, 67, 385-386.【2】
D. Chatterjee, S. Dasgupta. Visible light induced photocatalytic degradation of organic pollutants. Journal of Photochemistry and Photobiology C: Photochemistry Reviews, 2005, 6, 186–205.【3】
X. Xiao, C. Liu, R. Hu, X. Zuo, J. Nan, L. Lia, L. Wang. Oxygen-rich bismuth oxyhalides: generalized one-pot synthesis, band structures and visible-light photocatalytic properties. Journal of Materials Chemistry, 2012, 22, 22840-22843.【4】
X. Wang, K. Maeda, A. Thomas, K. Takanabe, G. Xin, J. Carlsson, K.Domen, M.Antonietti. A metal-free polymeric photocatalyst for hydrogen production fromwater under visible light, Nature Materials, 2008, 8, 76-80.
【5】
Z. Zhao, Y. Sun, F. Dong .Graphitic carbon nitride based nano composites: A review. Nanoscale, 2015, 7, 15-37.【6】
Hou Wang, X. Yuan, Y. Wu, H. Huang, X. Peng, G. Zeng, H. Zhong, J.Liang, M.M. Ren. Graphene-based materials: Fabrication, characterization and application for the decontamination of wastewater and wastegas and hydrogen storage/generation. Advances in Colloid and Interface Science, 2013, 195-196, 19-40.
【7】
W. Zhu, Z. Yang, L. Wang. Application of ferrous-hydrogen peroxide for the treatment of H-acid manufacturing process wastewater. Water Research, 1996, 30, 2949-2954.【8】
Y.F. Sasaki, S. Kawaguchi, A. Kamaya, M. Ohshita, K. Kabasawa, K.Iwama, K. Taniguchi, S. Tsuda. The comet assay with 8 mouse organs:
results with 39 currently used food additives. Mutation Research, 2002, 519, 103-119.
【9】
S. Srivastava, R. Sinha, D. Roy. Toxicological effects of malachite green. Aquatic Toxicology, 2004, 66, 319-329.【10】
W. Azmi, R.K. Sani, U.C. Banerjee. Biodegradation of triphenylmethane dyes. Enzyme and Microbial Technology, 1998, 22, 185-191.【11】
T. Gessner, U. Mayer. Triarylmethane and Diarylmethane Dyes.Encyclopedia of Industrial Chemistry. 2000.
【12】
H. Selcuk. Decolorization and detoxification of textile wastewater by ozonation and coagulation processes. Dyes and Pigments, 2005, 64, 217-222.【13】
A. Huren, Q. Yi, G. Xiasheng, Z.T. Walter. Biological treatment of dye wastewaters using an anaerobic-oxic system. Chemosphere, 1996, 33, 2533-2542.【14】
G.M. Walker, L.R. Weatherley. Adsorption of acid dyes on to granular activated carbon in fixed beds. Water Research, 1997, 31, 2093-2101.【15】
C. Namasivayam, D.J.S.E. Arasi. Removal of congo red from wastewater by adsorption onto red mud. Chemosphere, 1997, 34, 401-417.【16】
J.M. Wang, C.P. Huang, H.E. Allen, O.K. Cha, D.W. Kim. Adsorption characteristics of dye onto sludge particulates. Journal of Colloid and Interface Science, 1998, 208, 518-528.【17】
A. Mittal, V.J.M. Gajbe. Removal and recovery of hazardous triphenylmethane dye, Methyl Violet through adsorption over364-375.
【18】
L. Li, W. Zhu, P. Zhang, Z. Chen, W. Han. Photocatalytic oxidation and ozonation of catechol over carbon-black-modifiednano -TiO2 thin films upported on Al sheet. Water Research, 2003, 37, 3646-3651.【19】
C. Tang, V. Chen. The photocatalytic degradation of reactive black 5 using TiO2/UV in an annular photoreactor. Water Research, 2004, 38, 2775-2781.【20】
I. Gultekin, N.H. Ince. Synthetic endocrine disruptors in the environment and water remediation by advanced oxidation processes.Journal of Environmental Management, 2007, 85, 816-832.
【21】
S. Malato, J. Blanco, J. Caeres, A.R. Fernadez-Alba, A. Agura, A.Rodrı´uez. Photocatalytic treatment of water-soluble pesticides by photo-Fenton and TiO2 using solar energy. Catalyst Today, 2002, 76, 209-220.
【22】
K. Honda, A. Fujishima. Electrochemical photolysis of water at a semiconductor electrode. Nature, 1972, 238, 230845.【23】
J.H. Carey, J. Lawrence, H.M. Tosine. Photodechlorination of PCB’s in the presence of titanium dioxide in aqueous suspensions. Bulletin of Environmental Contamination and Toxicology, 1976, 16, 697-701.【24】
F. Han, V. Subba, R. Kambala, M. Srinivasan, D. Rajarathnam, R.Naidu. Tailored titanium dioxide photocatalysts for the degradation of organic dyes in wastewater treatment: A review. Applied Catalysis A:
General, 2009, 359, 25-40.
【25】
X. Chang, J. Huang, C. Cheng, Q. Sui , W. Sha , G. Ji , S. Deng , Gang Yu. BiOX (X = Cl, Br, I) photocatalysts prepared using NaBiO3 as the Bi source: Characterization and catalytic performance. Catalysis【26】
J. Zeng, J. Zhong, J. Li, Z. Xiang, X. Liu, J. Chen. Improvement of photocatalytic activity under solar light of BiVO4 microcrystals synthesized by surfactant-assisted hydrothermal method. Materials Science in Semiconductor Processing, 2014,27, 41-46.【27】
Transparency Market Research, 2013. Salicylic Acid Market for Pharmaceutical, Skin care, Hair care and Other Applications-Global Industry Analysis, Size, Share, Growth, Trends, and Forecast2013-2019.
【28】
Y. Lin , X. Sun, Q. Yuan, Y. Yan. Extending shikimate pathway for the production of muconic acid and its precursor salicylic acid inEscherichia coli. Metabolic Engineering, 2014, 23, 62–69.
【29】
M. Tian, B. Adams, J. Wen, R. M. Asmussen, A. Chen.Photoelectrochemical oxidation of salicylic acid and salicylaldehyde on titanium dioxide nanotube arrays. Electrochimica Acta, 2009, 54, 3799-3805.
【30】
M.D. González, E. Moreno, J. Quevedo-Sarmiento, A.Ramos-Cormenzana. Studies on antibacterial activity of waste waters from olive oil mills (alpechin): Inhibitory activity of phenolic and fatty acids. Chemosphere, 1990, 20, 423-432.
【31】
D. Ma, S. Huang, W. Chen, S. Hu, F. Shi, K. Fan. Self-Assembled Three-Dimensional Hierarchical Umbilicate Bi2WO6 Microspheres from Nanoplates: Controlled Synthesis, Photocatalytic Activities, and Wettability. Journal of Physical Chemistry C, 2009, 113, 4369-4374.【32】
P. Pawinrat, O. Mekasuwandumrong, J. Panpranot. Synthesis of Au–ZnO and Pt–ZnO nanocomposites by one-step flame spray pyrolysis and its application for photocatalytic degradation of dyes.Catalysis Communications, 2009, 10, 1380-1385.
【33】
X. Lin, T. Huang, F. Huang, W. Wang, J. Shi. Photocatalytic activity of a Bi-based oxychloride Bi4NbO8Cl. Journal of Materials Chemistry, 2007, 17, 2145-2150.【34】
W.L. Huang, Q. Zhu. Structural and electronic properties of BiOX (X=F, Cl, Br, I) considering Bi 5f states. Computational Materials Science, 2009, 46, 1076-1084.【35】
X. Xiao, W.D. Zhang. Facile synthesis of nanostructured BiOI microspheres with high visible light-induced photocatalytic activity.Journal of Materials Chemistry, 2010, 20, 5866-5870
【36】
J. Cao, X. Li, H. Lin, B. Xu, B. Luo, S. Chen. Low temperature synthesis of novel rodlike Bi5O7I with visible light photocatalytic performance. Materials Letters, 2012, 76, 181-183.【37】
X. Xiao, C. Xing, G. He, X. Zuo, J. Nan, L. Wang. Solvothermal synthesis of novel hierarchical Bi4O5I2 nanoflakes with highly visible light photocatalytic performance for the degradation of 4-tert-butylphenol. Applied Catalysis B: Environmental, 2014, 148-149, 154-163.【38】
C. Yu, J.C. Yu, C. Fan, H. Wen, Shengjie Hu. Synthesis and characterization of Pt/BiOI nanoplate catalyst with enhancedactivity under visible light irradiation. Materials Science and Engineering B, 2010, 166, 213-219.【39】
Z. Liu, J. Fangn, W. Xu, X. Xu, S. Wu, X. Zhu. Low temperature hydrothermal synthesis of Bi2S3 nanorods using BiOI nanosheets as self-sacrificing templates. Materials Letters, 2012, 88, 82-85.【40】
Xi. Zhang, L. Zhang, T. Xie, D. Wang. Low-Temperature Synthesis and High Visible-Light-Induced Photocatalytic Activity of BiOI/TiO2Heterostructures. Journal of Physical Chemistry C, 2009, 113, 7371-7378.
【41】
H. Wang, X. Yuan, Y. Wu, H. Huang, X. Peng, G. Zeng, H. Zhong, J.Liang, M.M. Ren. Graphene-based materials: Fabrication, characterization and application for the decontamination of
wastewater and wastegas and hydrogen storage/generation. Advances in Colloid and Interface Science, 2013, 195-196, 19-40.
【42】
Y. Jiang, H. Lina, W. Chung, Y. Dai, W. Lin, C. Chen. Controlled hydrothermal synthesis of BiOxCly/BiOmIn composites exhibiting visible-light photocatalytic degradation of crystal violet. Journal of Hazardous Materials, 2015, 28, 787-805.【43】
Department of Science Application and Dissemination, NationaK.S.Novoselov, V.I. Falko, L. Colombo, P.R. Gellert, M.G. Schwab, K.
Kim. A roadmap for graphene. Nature, 2012, 490, 192-200.
【44】
X. Zhoua, T.J. Shia, J. Wua, H. Zhoua. (001) Facet-exposed anatase-phase TiO2 nanotube hybrid reducedgraphene oxide composite:Synthesis, characterization andapplication in photocatalytic degradation. Applied Surface Science, 2013, 287, 359-368.
【45】
S.Y. Dong, Y.R. Cui , Y.F. Wang, Y.K. Li, L.M. Hu, J.Y. Sun, J.H.Sun. Designing three-dimensional acicular sheaf shaped BiVO4/reduced graphene oxide composites for efficient sunlight-driven photocatalytic degradation of dye wastewater. Chemical Engineering Journal, 2014, 249, 102-110.
【46】
W.S. Hummers, R.E. Offerman. Preparation of Graphitic Oxides.Journal of the American Chemical Society, 1958, 80, 1339.