Nanostructured materials for light harvesting applications

纳米结构半导体材料包括纳米线和纳米空洞阵列，是包括光伏在内的一系列光收集应用的引人注目的候选系统。与标准的块体或薄膜系统相比，它们的几何形状提供了几个优势，包括减少材料使用量以实现更低的成本和更可持续的生产，以及对由于使用横向提取方案而产生的块状晶体缺陷的固有容忍度，从而实现高载流子收集效率。这个项目将解决光学设计的需求，利用这些系统中的折射率周期性调制来实现电场限制和产生纳米级体积的强烈太阳吸收，以及表面态钝化的问题，这对这些系统来说是至关重要的，因为它们的表面积很大。本项目将重点研究III-V材料，特别是表现出自钝化行为的InP和相关合金。最近展示的这种材料体系的共形涂层能量选择接触为表面态钝化问题提供了一个有前途的解决方案。本项目包含模拟、制造和表征元素，但可以根据学生的兴趣进行调整。

Nanostructured semiconductor materials including nanowire and nanovoid arrays are compelling candidate systems for a range of light harvesting applications including photovoltaics. Their geometry offers several advantages over standard bulk or thin film systems including reduced materials usage for lower costs and more sustainable production, as well as an inherent tolerance to bulk crystal defects, resulting from the use of lateral extraction schemes which enable high carrier collection efficiency. This project will address the requirement for optical design which exploits the periodic modulation in refractive index in these systems to achieve E-field confinement and resulting strong solar absorption in nanoscale volumes, as well as the issue of surface state passivation which is critical for these systems due to their extensive surface area. This project will focus on III-V materials, in particular InP and related alloys, which exhibit a self-passivation behaviour. Recent demonstrations of conformally coated energy selective contacts for this material system offer a promising solution to the issue of surface state passivation. This project contains simulation, fabrication, and characterization elements, although it can be adjusted to match student interest.