EAGER: Investigating Optical Characteristics, Doping Levels and Current Matching in Perovskite/Si, Perovskite/GaAs/Si and Perovskite/III-V Ternary Semiconductors

摘要：非技术性： 晶体硅太阳能电池技术多年来一直主导着光伏技术市场，目前的市场份额为90%，这是由于其在半导体电子领域的广泛技术应用。有限光谱范围的光吸收和热化损失阻碍了硅太阳能电池效率的进一步提高。这项研究的奋进是面向提高效率超过单结硅太阳能电池的物理学所施加的热力学限制，通过合并不同的带隙半导体串联。这项研究将执行光学和电子优化方案，以提高太阳能电池，发光二极管和其他电子器件的吸收，光电流和效率。该研究将解决钙钛矿与硅和其他半导体集成的基本限制，并将影响多元化的技术和社会社区。这项研究的更广泛的影响在于：1）将研究结果纳入田纳西理工大学的光伏工程，物理电子学和光电工程等课程的课程改进中，2）招募女性，代表性不足的团体和退伍军人参与研究，3）组织推广活动，以提高高中，中学和社区对能源技术的认识。这将有助于增加工程和计算教育的长期入学率，为整个社会带来许多长期利益。 技术支持： 该研究计划的主要奖学金在于解决钙钛矿/Si串联技术面临的挑战，例如：1）钙钛矿吸收剂中的高亚带隙吸收; 2）钙钛矿/Si串联的低光转换效率; 3）相对较高的反射和寄生损耗;以及4）损害开路电压和填充因子。基于传输矩阵的光学吸收、反射和内部量子效率与每层波长的优化将提供关于每层中最大可实现吸收效率和光电流的见解。通过将传统的金字塔纹理与波长选择性中间反射器相结合来对波长相关吸收进行建模，将进一步提高串联效率。对串联中的每个子电池层进行基于掺杂浓度和厚度的电流密度与电压的模拟，并优化这些参数以匹配电流，将实现串联设计的最佳可能的光转换效率。这项研究将对固态照明、激光和薄膜电子器件的应用做出重大贡献。

Abstract: Nontechnical: Crystalline silicon solar cell technology has dominated the photovoltaic technology market for years with a current market share of 90%, owing to its wide technological applications in semiconductor electronics. Light absorption for limited range of the spectrum and thermalization losses hinder further increase in silicon solar cell efficiency. This research endeavor is geared toward increasing efficiency beyond the thermodynamic limits imposed by the physics of single-junction silicon solar cells by incorporation of different bandgap semiconductors in tandem. This research will perform optical and electronic optimization schemes to improve absorption, photocurrent and efficiency in solar cells, light emitting diodes and other electronic devices. The research will address fundamental limitations of integration of perovskites with silicon and other semiconductors and will impact a diverse technical and societal community. The broader impacts of this research lies in 1) incorporating research findings into curriculum enhancement of courses such as Photovoltaic Engineering, Physical Electronics and Optoelectronic Engineering at Tennessee Tech University, 2) recruiting female, underrepresented groups and veterans in research and 3) organizing outreach activities to foster increased awareness of energy technologies at the high-school, middle-school and community levels. This will help increase longer-term enrollment in engineering and computing education, yielding many long-standing benefits to society at large. Technical: The primary scholarship of the research plan lies in addressing the challenges facing perovskite/Si tandem technologies such as: 1) high sub-bandgap absorption in the perovskite absorber; 2) low photoconversion efficiency of perovskite/Si tandem; 3) relatively higher reflection and parasitic losses; and 4) compromising open-circuit voltage and fill factor. Transfer-matrix based optimization of optical absorption, reflection and internal quantum efficiency vs. wavelength of each layer will provide insights about maximum achievable absorption efficiency and photocurrent in each layer. Modeling of wavelength-dependent absorption by combining conventional pyramidal texture with wavelength-selective intermediate reflector will further increase the tandem efficiency. Doping concentration and thickness based current density vs. voltage simulations for each subcell layer in the tandem and optimizing those parameters to match the current will achieve the best possible photoconversion efficiency for tandem designs. This research will have significant contributions to solid-state lighting, lasing and thin-film electronic device applications.