在此研究著重於鍺(germanium)與鉑(Platinum)的二元奈米合金合成以及應用於染料敏化太陽能電池(dye-sensitized solar cells, DSSCs)以及電解水產氫(hydrogen evolution reaction, HER)。我們利用不同的前驅物莫爾比率及界面活性劑的差異去合成不同相態的合金。利用常見的液相熱注射法(hot injection method)，將奈米粒子的成核及成長階段分開，進一步得到大小、形狀較為均一的奈米粒子。接著用X光繞射圖譜及HR-TEM分析其相態與各結晶面情形，再利用SEM及TEM觀察奈米粒子的形狀、大小以及其排列狀況，進一步探討其可能的應用與性質。接著，我們將合成好的鍺鉑奈米合金材料應用在化學催化反應上，包含染料敏化太陽能電池(dye-sensitized solar cells, DSSCs)以及電解水產氫(hydrogen evolution reaction, HER)。利用簡單且非真空低成本塗佈方式，將均一的奈米粒子沉積在各式基板上，經由各式各樣的基礎電化學分析，可以知道鍺鉑奈米合金對於I-/I3-電解液系統有非常好的反應性，進一步將此材料應用在染敏太陽能電池系統中的對電極，並獲得8%以上與白金相差不遠的光電轉換效率。而在電解水系統上，利用三極式電化學測量系統，發現鍺鉑奈米合金粒子對於氫離子的吸脫附行為，也具有相當好的反應性。在固定10mA/cm2氫氣產出電流下能達到<0.1V的過電位，接著放大工作面積至5cm2，亦能達到相對的效果及其穩定性。

This study aims to synthesize Ge-Pt binary nanoalloys and their applications as catalysts for dye-sensitized solar cells and hydrogen generation. Via the tuning of mole ratio of precursors and surfactants, different phases of Ge-Pt alloy nanoparticles were synthesized. To obtain The Ge-Pt alloy nanoparticles with monodispersity in terms of size and shape were obtained due to efficient separation process of nucleation and growth in the liquid hot injection method. X-ray diffraction patterns and HR-TEM were used to analyze the phase and the crystalline structure of products, and SEM and TEM were used to observe the shape, size and the arrangement of nanoparticles, further to explore its possible applications and properties. Next, GePt nanoparticles were used as catalysts for chemical catalytic reactions of DSSCs (dye-sensitized solar cells) and HER (hydrogen evolution reaction). Through simple spray-deposited deposition methods, substrates coated with uniform nanoparticle film were obtained. We realize the catalytic properties of GePt nanoparticles toward I-/I3- redox reaction system through electrochemical analysis methods. Furthermore, applications of DSSC as a counter-electrode were demonstrated and the power conversion efficiency of over 8 % similar to Pt was obtained. On water splitting system, GePt nanoparticles possess excellent reactivity toward H+ adsorption/desorption behavior by the analysis of basic electrochemical test and analysis. GePt nanoparticles exhibit over potential of less than 0.1V in the condition of constant current of 10 mA/cm2, and maintain the efficiency and stability in the working area up to 5 cm2.

致謝……………………………………………………………………………………I
中文摘要…………………………………………………...…....................................II
Abstract……………………………………………………………………………..III
Table of Contents………………………………………………...............................IV
List of Tables…………………………………………………………………...…….V
List of Figures………………………………………………………………..……...VI
Chapter 1 Thesis Introduction……………………….…………………….………..1
1.1 Introduction on Nanomaterials………………………………………………….1
1.2 Hot solvent methods…………………………………………………….………2
1.3 Reference…………………………………………………………………..……4
Chapter 2 Synthesis of Ge-Pt Alloy Nanomaterials for Energy Device Applications…………………………………………..………………………………5
2.1 Introduction………………………………………………………………..……5
2.2 Experimental Section…………………………………………………….……16
2.2.1 Chemicals………………………………………………………...….……16
2.2.2 Synthesis of platinum-germanium alloy nanocrystal……………..………16
2.2.3 Counter-electrode preparation…………………………………….………18
2.2.4 Dye-sensitized solar cell assembly…………………………………..……19
2.2.5 HER working electrode fabrication………………………………….……19
2.2.6 RHE reference electrode preparation……………………………..………20
2.2.7 Characterization and Measurement…………………………….…………20
2.3 Result and Discussion…………………………………………………………23
2.4 Conclusion…………………………………………………………………..…49
2.5 Reference………………………………………………………………………50

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