- 學位論文
微(奈)米二氧化鈦電聚合反應於空污防治及太陽能電池導電層製備之應用研究
Studies on the application of Electro-polymerization of Micro (Nano) Sized TiO2 Powder on the Air Pollution Control and the Manufacturing of Electrical Layer for Solar Cells
摘要
奈米工程技術自二十世紀以來已經成為世界科技的趨勢，如何利用奈米科技在環境上分解去除有機污染物質則是新興的議題。過去幾年本研究室對奈米光觸媒研究初步證實奈米二氧化鈦能聚合水中溶解之苯乙烯。因此本研究方向主要分為兩大部分：(1)首先利用二氧化鈦聚合苯乙烯，藉以探討溫度與尺寸效應於聚合反應之影響及其產物之結構特性分析。(2)將所得之高分子複合物作為染料敏化太陽能電池導電層材料，藉以製造出光電能轉化效率更高且低成本之電池。 在第一部分首先以二氧化鈦於不同溫度下聚合苯乙烯之單體，經由膠體層析滲透儀及傅立葉紅外線光譜儀之分析結果可知，其產物之重量平均分子量會受到聚合環境溫度之影響而產生變化，且在光譜中亦可得知於高溫及低溫環境下進行聚合反應，其訊號3000 cm-1芳香族類之官能基及1400 cm-1之烯類官能基訊號有明顯增強之趨勢。由此可推測低溫及高溫聚合環境下有助於二氧化鈦聚合苯乙烯；且二氧化鈦的添加量亦會影響其聚合反應。 接著利用不同尺寸之二氧化鈦分別以紫外光活化及未活化後進行氣相苯乙烯單體之聚合處理。並於不同處理時間下以氣相層析儀進行其濃度分析，其結果可知經照光活化後之奈米尺寸之二氧化鈦聚合去除苯乙烯之效果為最佳，其去除率可達97.57％。其產物藉由固態核磁共振儀之分析得知試樣化學位移180至400 ppm之訊號來自於聚苯乙烯苯環之碳訊號；但化學位移90至160 ppm之訊號其來源是不屬於聚苯乙烯，反而與二氧化鈦聚合乙炔之產物結構較為類似。以傅立葉紅外線光譜儀分析產物之官能基結果可知於3000 cm-1為芳香族類官能基訊號；在2940 cm-1為亞甲基之訊號；在1400 cm-1為烯類之官能基訊號；而在1000至900 cm-1為乙烯基之訊號。經由文獻聚乙炔之傅立葉紅外線光譜圖比對後，可證實其複合物為先前所推測之結構體。且將樣品利用熱視差掃描分析儀進行方析，其結果亦可得知產物於90-100℃間具有ㄧTg；於160℃有ㄧTg。而在膠體層析滲透儀之分析結果得知產物之重量平均分子量均大於10000是屬於高分子複合物，且其結構同時具有聚苯乙烯及聚乙炔特性之共聚合體。 第二部份則將合成之高分子複合物製成染料敏化太陽能電池，並測其光電轉換效能。由結果可知，純二氧化鈦浸泡染料後所製成之電池其光電轉換率較低，僅有以高分子複合物所製成之電池效能的一半。且以高溫及低溫之環境下進行聚合反應所得之高分子複合物製成之電池其光電轉換效能亦比室溫環境下進行聚合反應所得之高分子複合物製成之電池其轉換率高1.80倍。
並列摘要
Nano - engineering technology has become the most growing trend in the world since the 20th century. How to apply nanotechnology on the environment in order to remove the decomposition of organic pollutants is the emerging subject. During the past years a preliminary study of Nano-photocatalists confirmed that Nano-TiO2, can polymerize dissolved styrene in water. Due to the direction of the study, it was divided in two major sections: (1) we first use styrene polymerization to explore the effect of temperature and size effect on polymerization and its influence in the characteristics of the product thru analysis of characteristics. (2) As a second part of the experiment, electric layers of dye-sensitized solar cells were be derived as a material to create photovoltaic energy, with a more efficient conversion and low costs of the cells. In the first section of this experiment we used TiO2 polymerization of styrene monomer at different temperatures. From the results of gel permeation chromatography and furrier infrared spectroscopy analysis, we were able to that the average molecular weight of this product was subjected to ambient polymerization temperature effect and then to variation result. Can also be learned that in high and low temperatures, polymerization environment can proceed to react at 3000 cm-1 which is the signal of aromatic functional group, and at 1400 cm-1 which is the signal of alkaline functional enhance; this might be surmised at low and high temperature, to conduct it to environment polymerization of styrene monomer, where the addition of TiO2 can affect its polymerization reaction. Different sizes of TiO2 where exposed in to UV light, after that procedure some of the samples where activated and another part of them was not activated, after this application we proceed to polymerization process of vapor styrene monomer. In different processing times, chromatography analysis was used to measure gas concentration, the result can be known by light activation of Nano-TiO2 polymerization, where the removal of styrene gives as a result the best effect with a removal rate of 97.57%. The obtained product was in a solid-state; nuclear magnetic resonance analysis can be aware from 180 to 400 ppm of chemical shift signals of the polystyrene by carbon signal; however the chemical shift signals from 19 to 160ppm are not from polystyrene. Instead TiO2 polymerization of acetylene structure from the product is more similar. Fourier infrared spectroscopy was used to analyze the infrared spectrum of the product, showing an aromatic functional group signal at 3000 cm-1, as the same showed a methylene functional group signal at 2940 cm-1, an alkaline functional group signal at 1400 cm-1 , and a terminal vinyl functional group signal from 1000 to 500 cm-1 .If this product is compared with literature about Fourier infrared spectrum of polyacetylene, previous conjunction on this polymer can be confirmed. Using differential scanning calorimetric analysis of polymers, as a result we can obtain a product formed at 90 to 100°C , having a Tg, and a product formed at 160°C , having a Tg. From the gel permeation chromatography we can obtain the average of molecular weight, which is greater than 1000 which is a polymer compound, we can obtain too, the structure characteristics of this product, it was found that it posses polystyrene and polyacetylene of copolymers. In the second section of this experiment, synthesization of polymer made of dye-sensitized solar cells was performed, as the same the measure of photovoltaic energy conversion. As a result energy conversion rate of photovoltaic cells immersed in pure TiO2 showed to be low when compared to one half of the solar cells.