本論文利用動態光散射(DLS)、UV-vis吸收光譜、PL光激發光光譜、偏光顯微鏡(POM)、掃描式電子顯微鏡(SEM)、以及穿透式電子顯微鏡(TEM)進行一系列老化時間、溫度效應及混摻不同奈米碳材對於在共軛高分子(P3HT)與二甲苯溶液中的凝膠化行為、聚集結構及其光物理性質影響的研究，本研究結果獲得以下的結論：
首先探討P3HT在二甲苯溶劑中的聚集行為對其光物理特性影響研究。研究中發現P3HT/二甲苯溶液隨老化時間對溶液中的P3HT分子聚集結構及凝膠化影響。研究發現P3HT/二甲苯溶液隨老化時間增加而逐漸呈現凝膠化結構。因此在P3HT/二甲苯溶液的光物理性質(UV-vis吸收光譜及PL光激發光光譜)，發現隨老化時間的增加，P3HT/二甲苯溶液中的P3HT分子鏈聚集及結晶化所形成0-1及0-2能量轉移峰(640及690nm)強度明顯隨老化時間增加而增加。這些現象均表示在P3HT/二甲苯溶液體系隨老化時間的增加將呈現相分離現象，而在富高分子相中P3HT共軛高分子鏈之間逐漸聚集形成片狀的聚集結構或結晶化，因此降低P3HT共軛高分子間的能量轉移。相對的，在升溫過程中P3HT/二甲苯溶液中的聚集結構或結晶化結構逐漸瓦解形成均一性溶液，這現象意味P3HT聚集結構在升溫過程中逐漸消失，因此P3HT/二甲苯凝膠的PL光激發光或UV-vis吸收光譜中的特性吸收峰將逐漸下降。
另一方面，探討不同混摻比聚噻吩及奈米碳球(P3HT/PCBM)在二甲苯溶液之聚集結構及光電性質的影響分析。在研究中發現P3HT/PCBM混摻於二甲苯溶液隨老化時間增加發現P3HT將會被PCBM吸附而影響P3HT分子鏈在溶液中的聚集行為及凝膠化行為。由UV及PL實驗結果得知當PCBM的含量增加，P3HT/PCBM混摻二甲苯溶液之0-1及0-2單重態能量轉移峰的行為明顯受PCBM含量的增加而下降，這現象表示P3HT/PCBM混摻於二甲苯溶液體系中的P3HT分子鏈的聚集行為會因PCBM的加入而改變。研究中發現老化時間效應對不同重量比P3HT/PCBM混摻於二甲苯溶液的觀測中發現如下步驟：(1)由均一的P3HT/PCBM混摻於二甲苯溶液利用相分離機制轉變成不均一的結構。(2)在富P3HT/PCBM混摻相中P3HT分子鏈將聚集形成奈米晶鬚，相對的PCBM分子將聚集形成PCBM聚集體。(3)隨老化時間的增加P3HT奈米晶鬚將聚集形成望狀結構或聚集形成P3HT片狀結構，相對的PCBM將堆疊形成PCBM奈米晶體。(4)PCBM奈米晶體將會吸附P3HT片狀結構於PCBM奈米晶體表面而將P3HT片狀結構轉變成不規則並堆疊形成類似花朵般的聚集體。因此將會破壞純P3HT分子鏈於二甲苯溶劑中的聚集及凝膠化行為，並改變P3HT/PCBM混摻二甲苯溶液的UV-vis及PL光譜性質。相對的P3HT/PCBM混摻於二甲苯溶液的凝膠化及聚集結構式一熱可逆性性質，因此隨溫度的增加，P3HT/PCBM混摻於二甲苯老化凝膠中的聚集結構將會受溫度而瓦解，在P3HT/PCBM混摻二甲苯凝膠的相轉變溫度隨PCBM含量的增加而往低溫方向偏儀也證明PCBM分子將會抑制溶液體系中P3HT分子鏈之間的聚集。
最後分析Graphene 含量的增加對P3HT/Graphene混摻二甲苯溶液在不同條件下對凝膠行為、聚集結構及其光物理性質變化影響分析。研究中發現老化時間效應對不同重量比P3HT/Graphene混摻於二甲苯溶液的相分離行為呈現如下步驟：(1)由均一的P3HT/Graphene混摻於二甲苯溶液利用相分離機制轉變成不均一的結構。(2)在富P3HT/Graphene混摻相中P3HT分子鏈將聚集形成奈米晶鬚，相對的Graphene分子將聚集形成Graphene聚集體。(3)隨老化時間的增加P3HT奈米晶鬚將會被Graphene聚集體吸附而形成蠶繭狀的聚集結構。由於P3HT/Graphene混摻於二甲苯溶液體系中隨Graphene含量的增加，在老化過程中將會破壞純P3HT分子鏈於二甲苯溶劑中的聚集及凝膠化行為，因此導致P3HT/Graphene混摻二甲苯溶液了凝膠化時間的增加並改變P3HT/Graphene混摻二甲苯溶液的UV-vis及PL光譜性質。因此在P3HT/Graphene混摻形成蠶繭狀的聚集結構的SEM照片中發現P3HT分子鏈聚集形成90-200nm直徑的奈米晶鬚結構並密緻的吸附在Graphene結構上而形成類似蠶繭的結構。在TEM觀測中可確認P3HT/Graphene蠶繭結構內部為P3HT奈米晶鬚是由P3HT分子鏈的a軸延奈米晶鬚成長方向堆疊而成，並且這些P3HT奈米晶鬚相互交錯呈網狀結構形成外觀為蠶繭的P3HT/Graphene聚集體。

In this work, we provided insights into effect of the carbon nanomaterials; such as phenyl-C61-butyric acid methyl ester (PCBM) and graphene, aging time and temperature on the gelation mechanism, aggregates structure and its effect on the photophysical properties (UV-vis absorption and Photoluminescence spectra) of Poly(3-hexylthiophene) (P3HT) conjugate polymer in xylene solutions with Dynamic light scattering (DLS), Polarized optical microscopy (POM), UV-visble absorption (UV-vis), and Photoluminescence (PL) spectra, Wide-angle X-ray diffraction (WAXD), scanning electronic microscopy (SEM) and transmission electronic microscopy (TEM) techniques. Firstly, we focus on the gelation mechanism of P3HT and induce its photophysical properties in xylene solution as a function of concentration of P3HT. DLS indicated that the aggregation structure characterized by the normalized intensity-intensity correlation function (A()-1) and decay time (t) of P3HT in the xylene solution depended strongly on concentration and aging time, where the conjugated chains exhibited a more aggregated as concentration and aging time were raised. Dynamic light scattering and optical microscopy revealed that the gelation was driven by a phase-separation occurred through a spinodal decomposition mechanism, therefore, the gelation mechanism was influence on its photophysical properties of P3HT/xylene solution with aging time. As increase in the aging time, P3HT polymer segments association or crystallization to form aggregates in P3HT/xylene solution. Thus, the intensities of 0-1 and 0-2 singlet energy transformation (640 and 690 nm) in PL spectrum increase remarkable with increasing aging time. The phenomenon may be let us concluded that P3HT/xylene solution occurs the phase-separation mechanism to form a P3HT-enriched domain and an isotropic-enriched domain with aging time as raise. The P3HT-enriched phase was mesomorphic, consisting of some nanowhisker or nanowire morphology and some sheetlike aggregates or membranes of P3HT, which dominated the UV-vis and PL behavior of the gel. On the other hand, the P3HT aggregates and crystallized structures could be disrupted by heating to ca. 45-55 oC as a function of concentration of P3HT, above which the corresponding UV-vis and PL spectra displayed a blue shift because of reduced amount of the aggregates of P3HT for the isotropic P3HT/xylene solution.
Then, we provided insights into effect of the weight ratios of PCBM in P3HT/PCBM nanocomposites, temperature, and aging time on the aggregation, and gelation mechanism of P3HT/PCBM/xylene solution and its effect on the photophysical properties of blended P3HT/PCBM in solution at room temperature. UV-vis spectrum, optical microscopy and SEM revealed that the gelation of P3HT/PCBM/xylene solution was driven by phase-separation occurred through P3HT conjugated polymer association and PCBM molecules aggregation in the P3HT/PCBM-enriched domain. Although the phase-separation could proceed to the late stage, the interconnected morphology of P3HT was restrained by the PCBM molecules aggregates to decrease the gel property of the system. The phase-separation behavior of P3HT/PCBM in xylene solution as separate in to four steps: (1) the homogenous P3HT/PCBM/xylene fresh solution occurrence the phase-separation mechanism to form a P3HT/PCBM-enriched domain and a isotropic-enriched domain, (2) in the P3HT/PCBM-enriched domains, P3HT polymer chains associate to form nanowhisker whereas, PCBM molecules aggregate to form sheet-like aggregates with aging time, (3) Upon prolonged isothermal aging time, the nanowhiskers aggregate in to a three-dimensional network structure, and PCBM molecules associate in to nanocrystals with π-π stacked interaction force, and (4) the sheet-like P3HT aggregates were adsorb by PCBM nanocrystals forming flower-like aggregates within P3HT/PCBM-enriched phase. The gelation mechanism dominates the UV-vis and PL behavior with aging time. However, the aggregates of P3HT/PCBM nanocomposite could be disrupted by temperature heating to ca. 40-55 oC as a function of content of PCBM. At higher PCBM content resulting lower phase transition temperature because of reduced the amount of P3HT polymer chains within the aggregates.
Finally, we provided insights into effect of the weight ratios of graphene in P3HT/graphene nanocomposites, temperature, and aging time on the aggregation, and gelation mechanism of P3HT/graphene/xylene solution and its effect on the photophysical properties of blended P3HT/graphene in solution at room temperature. The gelation behavior, UV-vis and PL spectra of P3HT/graphene/xylene solution dominate by the graphene content. The phase-separation behavior of P3HT/graphene in xylene solution as separate in to three steps: (1) the homogenous P3HT/graphene/xylene freshly solution occurrence the phase-separation mechanism in to a P3HT/graphene-enriched domain and a isotropic-enriched domain, (2) in the P3HT/graphene-enriched domains, P3HT polymer chains associate to form nanowhisker whereas, PCBM molecules aggregate to form sheet-like aggregates with aging time, (3) Upon prolonged isothermal aging time, the P3HT nanowhiskers were adsorb by graphene aggregates forming cocoon-like aggregates within P3HT/graphene-enriched phase. Within the cocoon-like aggregates, we confirm that the P3HT polymer chains self-assembled for nanowhiskers through π-π stacked interaction and aligned along the nanowhisker axis grow.

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