High Efficiency InN-Based Quantum Dot Solar Cells

The goal of the Proposed Phase I Program is to employ Nanostructured nitride based materials in an advanced device design to enhance the tolerance of solar cells to extreme environments while maintaining high solar electric power conversion efficiency. By using InN-based quantum dots embedded within a higher band gap GaN barrier material, a larger fraction of the solar spectrum can be harnessed while minimizing the effects of high temperatures with this promising photovoltaic device. The wide range of energies accessible to InN-based materials provides unique flexibility in designing quantum dot solar cell structures. Phase I work will demonstrate the feasibility of synthesizing device quality InN-based quantum dots. InN quantum dot assemblies will be grown on GaN templates via metalorganic chemical vapor deposition (MOCVD). More importantly, strong room temperature photoluminescence has been observed, with peak emission energies ranging from the infrared to the ultraviolet. These promising optical properties suggest it will be possible to build structures incorporating InN quantum dots within a GaN p-n junction to use the basic concepts of quantum dot solar cells during the Phase I effort. Ultimately our approach provides a pathway for realizing solar cells with over 2,000 W/kg of specific power and power conversion efficiency approaching 60%.