【作者】 刘智勇；

【导师】 何大伟；

【作者基本信息】 北京交通大学 ， 光学， 2011， 博士

【摘要】 目前有机聚合物太阳能电池的光电转换效率较低,国际科研人员的科研重点集中在如何通过聚合物与无机材料复合来提高器件的光伏性能。石墨烯具有最高的载流子迁移率和最大的比表面积,能够很好的和聚合物材料形成接触。MEH-PPV和P3HT是聚合物光伏材料中非常成熟的两种,本文重点研究氧化石墨烯与这两种聚合物材料复合器件的光伏机理和性质,主要研究内容如下：1.以Hummers法为基础制备了氧化石墨烯,用异氰酸本质对氧化石墨烯进行还原处理,得到还原后的氧化石墨烯。通过XRD、FTIR、SEM、TEM和Raman光谱等表征手段对产物进行了表征,通过四探针测量仪对产物进行了测试。制备出了达到实验要求的氧化石墨烯,经过还原处理的氧化石墨烯的电导率有了很大的提高,呈现出由氧化石墨向石墨的变化。2.我们采用在聚合物中掺杂经过还原的氧化石墨烯,制备了结构为ITO/聚合物-氧化石墨烯/Al的光伏器件,研究了不同氧化石墨烯浓度与开路电压、短路电流和填充因子的关系。通过光致发光和器件的I-V曲线,得出结论氧化石墨烯起到了电子受体的作用,防止了自由电子空穴的耦合,氧化石墨烯的量子隧穿效应可以提高器件的载流子迁移率,增大短路电流和填充因子。3.我们提出了结构为ITO/聚合物-氧化石墨烯-多壁碳纳米管/Al的器件,研究了不同氧化石墨烯浓度和不同多壁碳纳米管浓度对器件短路电流和填充因子的影响。我们认为氧化石墨烯作为电子受体可以改善电子传导,多壁碳纳米管可以起到传导空穴的作用。在相同氧化石墨烯浓度的情况下,P3HT为主体材料的器件光电转换效率比以MEH-PPV为主体材料的器件光电转换效率更高,P3HT的最高效率也要比MEH-PPV的最高效率高。4.我们提出了结构为ITO/P3HT:PCBM氧化石墨烯/Al的器件,进一步研究了不同氧化石墨烯浓度与器件短路电流和填充因子的关系。表明氧化石墨烯可以起到链接小分子PCBM的作用,形成电子的三维空间传输网络,提高载流子迁移率的作用。更多还原

【Abstract】 ABSTRACT: Recently, the power conversion efficiency (PCE) of organic photovoltaic is very low; the research has concentrate on the composite of organic material and inorganic material. The graphene oxide has the highest carrier mobility and big specific surface area, has very good of interfacial face at the graphene oxide and polymer. The MEH-PPV and P3HT is mature for the rearch. The rearch content is the photovoltaic character of composite polymer and graphene oxide. This the main contents of my paper:1. We produced the graphene oxide by Hummers way and deoxidize the graphene oxide by isopropyl isocyanate. To token the graphene oxide by XRD、FTIR、SEM、TEM and Raman spectrum, to test the character of graphene oxide by Four-point probe. We has produced the graphene oxide, the conductivity of graphene oxide has very big improved.2. We produced the ITO/polymer-graphene oxide/Al devices by introduces graphene oxide into the polymers. We have rearched the open circuit voltage, short-circuit current and fill factor of different graphene oxide content. By the photoluminescence andⅠ-Ⅴ, we have found that the graphene oxide has acted as the electron acceptor, avoid the coupling of electron and hole. And then, the quantum tunneling of graphene oxide has enhance the carrier mobility of composite films, augment the short-circuit current and PCE.3. We has produced the ITO/polymers-graphene oxide-MWCNTs/Al devices, and reached the effect of open circuit voltage, short-circuit current and fill factor for different graphene oxide content and MWCNTs content. We discover that the graphene oxide acted as the electron acceptor has improved the electron transported, the MWCNTs has improved the hole transported. For the same graphene oxide content, the PCE of P3HT is good compared with the PCE of MEH-PPV. For the biggest PCE, the PCE of P3HT has higher compared with PCE of MEH-PPV.4. We has produced the ITO/P3HT:PCBM-graphene oxide/Al devices. We has rearch the relation of short-circuit current and fill factor for the different graphene oxide content. The experiment has show that the graphene oxide has the effect of link PCBM, form the transported network of electron, enhance the carrier mobility of composite films.更多还原