This dissertation describes several key developments in semiconductor devices and technologies designed for solar power conversion and other applications. The first development is of two new growth techniques for producing large-area two-dimensional molybdenum disulfide (MoS2). Such two-dimensional materials have the potential to miniaturize photovoltaic volume and mass by orders of magnitude without sacrificing performance. While large-scale 2D-material-based photovoltaics have not yet been realized, large-area growths such as those described in this dissertation provide meaningful progress toward that goal. The described techniques enable 2D MoS2 thickness control on the order of angstroms and increase 2D MoS2 growth speed by two orders of magnitude relative to the current state of the art. Furthermore, the grown materials are developed into preliminary optoelectronic devices, with performance characterization, as a step toward more advanced photovoltaic devices. The second development presented in this dissertation is the design, fabrication, test, and analysis of a kW-scale hybrid spectrum-splitting photovoltaic module. The module is designed to be transmissive to incident infrared radiation, allowing for infrared light to be separately collected by a thermal receiver, while simultaneously collecting high-energy visible and ultraviolet light via photovoltaics. A system is built and tested on an outdoor testbed and shows 75% total power conversion efficiency (thermal and electric) of the incident solar spectrum, surpassing the capability of conventional photovoltaics. This high efficiency and combination of electrical and thermal power accelerates solar energy penetration into new applications requiring multiple power streams. Across these varied length scales, this dissertation gives glimpses into new innovations throughout the photovoltaic and semiconductor fields and aims to share this knowledge and outlook with the next generation of researchers.
