Processing conformal polymer photovoltaic thin-films on textured topographies for photonic management

PI：Chaudhary，SumiteProposal编号：1236839机构：爱荷华州立大学标题：在纹理地形上处理共形聚合物光伏薄膜以进行光子管理有机光伏(OPV)技术是一种潜在的广泛应用的可持续和经济的太阳能-电力转换方法，因为它有望使用溶液相工艺在可弯曲的衬底上进行卷曲到卷曲制造。在OPV器件中，在由两种有机材料(电子给体和受体)组成的两相溶液中，在衬底上涂覆一层薄的lm(有源层)。然而，这种器件中的光学损耗很高，效率很低。该项目引入了一种新的光捕捉处理范例，并提高了效率？在亚微米级纹理形貌上涂覆聚合物OPV共混物的保形层。(1)OPV的有源层将被旋涂在织构的表面上，并将建立工艺-结构-性能的关联。(2)将开发一个模型和在纹理地形上涂覆时的蒸发的理论框架，以告知实验任务最佳地形尺寸和适当的加工条件。然后，新出现的知识发现将被用于使用医生刀片技术(卷到卷制造的原型)来制造纹理OPV细胞。这个项目的总体目标是建立一个能够在这样的表面上实现共形聚合物的拓扑库和工艺条件库，从而实现有效的光捕获和更高的太阳能-电转换效率。拟议的研究将薄-微结构的范例引入三维(纹理方法)，从而有望克服与不同的光子和电荷传输尺度相关的经典的光学光伏权衡。拟议研究的智力价值和变革性在于试图回答以下基本问题？下面的地形和工艺条件的尺寸应该是多少，才能不仅在超薄的聚合物层中实现有效的光吸收，而且还可以在这些地形上共形地涂覆这样的涂层？制造和表征，包括光学和器件建模，将与建模相结合，以实现这一总体目标。除了OPV的缺陷外，拟议的研究还将对一个更普遍的问题产生影响，即在含有地形特征的功能衬底上涂覆薄膜层。这一问题对各种工程、工业和物理应用具有巨大的意义。拟议的工作是高度跨学科的，结合了光伏器件实验工作的元素，以及流体力学和相变的计算工作。该项目的多学科组成部分将被整合到一个更大的教育努力中，为学生提供坚实的科学计算和可再生能源基础。我们的教育和外展计划进一步包括(1)现有有机电子学课程的模块和一门新的多尺度制作课程，(2)开发一个指导计划，将研究生和本科生联系起来，特别强调代表不足的群体？目的是增加招聘和留住人员；(3)开展外联活动，向K-12社区展示计算机在科学和技术方面的关键作用。为此，PI将创建教育模块，包括对OPV过程的身临其境的模拟，将向Ames高中生演示；(4)为爱荷华州现有和未来的K-12教师准备课程模块和基于玩弄技术的动手组件计划；(5)继续与机械工程专业的女性合作？在吸引女性和少数族裔本科生方面。

PI: Chaudhary, SumitProposal Number: 1236839Institution: Iowa State UniversityTitle: Processing conformal polymer photovoltaic thin-films on textured topographies for photonic managementOrganic photovoltaic (OPV) technology is a potentially widespread approach for sustainable and economical solar-electric conversion owing to its promise of roll-to-roll fabrication on flexible substrates, using a solution-phase process. In an OPV device, a thin film (active-layer) is coated on a flat substrate from a biphasic solution consisting of two organic materials (electron donors and acceptor). However, optical losses in such a device are high and efficiencies are low. This project introduces a new processing paradigm for light-trapping and higher efficiencies ? coating conformal layers of polymeric OPV blends on sub-micron scale textured topographies. (1) Active-layers of OPVs will be spin-coated on textured topographies and processing-structure-property correlations will be established. (2) A theoretical framework to model fluid-flow and evaporation while coating on textured topographies will be developed to inform the experimental task of best topographical dimensions and appropriate processing conditions. Knowledge discovery emerging will then be used to fabricate textured OPV cells using doctor-blading technique (a prototype for roll-to-roll manufacturing). Overall objective of this project is to establish a library of topographies and processing conditions that are amenable to achieving conformal polymer films on such surfaces, so that effective light trapping and higher solar-electric conversion efficiencies are realized.The proposed research takes the thin-film paradigm into the third dimension (textured approach), thus promising to overcome the classic OPV trade-off pertaining to dissimilar photonic and charge-transport scales. Intellectual merit and transformative nature of proposed research lies in the attempt to answer the following fundamental question ? What should be the dimensions of underlying topographies and processing conditions, such that not only effective optical absorption is achieved in ultra-thin polymer layers, but it is also possible to coat such films, conformally on these topographies? Fabrication and characterization, including optical and device modeling will be coupled with fluid-flow modeling to achieve this overall objective. Other than the field of OPVs, the proposed research will also have implications on a more general problem of thin film coating over functional substrates containing topographical features. This problem is of enormous significance for various engineering, industrial and physical applications.The proposed work is highly interdisciplinary combining elements from experimental work on photovoltaic devices, and computational work on fluid-mechanics and phase-transformation. The multidisciplinary components of the project will be integrated into a larger educational effort to offer students a solid foundation in scientific computing and renewable energy. Our education and outreach plans further include (1) modules for existing course on organic electronics and a new course in multiscale mdoelling, (2) developing a mentoring program, linking graduate with undergraduate students, with special emphasis on underrepresented groups ? with an objective of increasing recruitment and retention, and (3) outreach activities that demonstrate to the K-12 community the crucial role of computing in science and technology. To this end, the PIs will create educational modules involving immersive simulations of OPV processes which will be demonstrated to Ames high school students, (4) preparing modules for the lesson and hands-on components based Toying With Technology program, in place at Iowa State for the current and future K-12 teachers, (5) continuing to work with ?Women in Mechanical Engineering? in engaging women and minority undergraduate students.