Additive Manufacturing of Conformal Solar Cells via Xenon-Light-Assisted Sintering

符合三维物体形状的太阳能电池作为自持装置（例如，建筑物中的智能窗，以及用于监测汽车和飞机中的结构完整性的传感器）。用于制造共形太阳能电池的常规路线是将其功能层制造到柔性中间聚合物片材上，并将片材附接到所需的三维物体上。在附着过程中，片材变形以使其符合物体的三维形状。片材的这种变形经常导致电池功能层的破裂和电池功能的损失。该奖项支持对一种新的增材制造工艺的科学研究，该工艺用于在三维物体上制造保形太阳能电池，而不使用任何中间聚合物片材。该研究成果将使太阳能电池作为可再生能源在能源、通信、航空航天和汽车行业的自我维持设备中得到更广泛的应用。该项目旨在开发新的增材制造工艺，通过整合喷墨沉积和氙光辅助纳米颗粒烧结来制造保形太阳能电池。研究目的是了解物理化学机制之间的相互作用（即，光学诱导的纳米颗粒加热、温度升高诱导的纳米颗粒之间的质量传递、以及质量传递诱导的化学反应），这些是纳米颗粒特性（尺寸和化学计量）与烧结材料性质（密度和化学组成）之间关系的基础。将通过耦合纳米颗粒的光学加热（通过电磁有限元分析），纳米级传质和反应动力学（使用分析模型）以及温度和应力的中尺度演变（通过烧结的中尺度有限元分析）来开发基于物理的模型。某些模型参数（例如，纳米颗粒尺寸分布和熔点）将通过使用量热法、分光光度法和光谱法测量纳米颗粒特性来校准。为了验证该模型，将使用新工艺烧结具有不同特性的纳米颗粒，并将烧结材料特性（使用电子显微镜，X射线衍射和红外成像测量）与模型预测进行比较。该经验证的模型将用于预测纳米颗粒特性对烧结材料性能的影响，以及对工艺过程中物理化学机制的关键指标的影响（例如，沉积的纳米颗粒的温度上升速率、沉积的纳米颗粒中的收缩和应力、以及沉积的纳米颗粒中未反应的材料与具有改变的相的材料的比率）。

Solar cells that conform to the shape of a three-dimensional object are desirable as a renewable energy source for self-sustaining devices (e.g., smart windows in buildings, and sensors for monitoring structural integrity in automobiles and airplanes). The conventional route for manufacturing conformal solar cells is to fabricate their functional layers onto a flexible intermediary polymer sheet, and attach the sheet onto the desired three-dimensional object. During attachment, the sheet is deformed so that it conforms to the object's three-dimensional shape. This deformation of the sheet frequently causes cracking of the cell's functional layers and a loss in the cell's functionality. This award supports scientific investigations on a new additive manufacturing process for fabricating conformal solar cells onto a three-dimensional object, without using any intermediary polymer sheet. Results from this research will enable wider use of solar cells as a renewable energy source for self-sustaining devices in energy, communications, aerospace, and automotive industries.This project aims to develop the new additive manufacturing process for conformal solar cells by integrating inkjet deposition and xenon-light-assisted nanoparticle sintering. The research objective is to understand the interaction between physio-chemical mechanisms (i.e., optically induced nanoparticle heating, temperature rise induced mass transport between nanoparticles, and mass transport induced chemical reactions) that underlie the relationship between nanoparticle characteristics (size and stoichiometry) and sintered material properties (density and chemical composition). A physics-based model will be developed by coupling optical heating of nanoparticles (via electromagnetic Finite Element Analysis), nanoscale mass transfer and reaction kinetics (using analytical models), and mesoscale evolution of temperature and stress (via mesoscale Finite Element Analysis of sintering). Certain model parameters (e.g., nanoparticle size distribution and melting points) will be calibrated by measuring nanoparticle characteristics using calorimetry, spectrophotometry, and spectroscopy. To validate the model, nanoparticles with varying characteristics will be sintered using the new process, and sintered material properties (measured using electron microscopy, X-ray diffraction, and infrared imaging) will be compared to model predictions. This validated model will be used to predict the effects of nanoparticle characteristics on sintered material properties, and on key indicators of physio-chemical mechanisms during the process (e.g., rate of temperature rise of deposited nanoparticles, shrinkage and stresses in deposited nanoparticles, and ratio of unreacted material to material with changed phase in deposited nanoparticles).