I-Corps: High-value surface modifications with nanomaterial thin films

这个I-Corps项目旨在证明使用高反射和光散射纳米颗粒薄膜作为太阳能电池背反射器的商业可行性，目标是取代高真空处理技术。背反射器可以使太阳能电池的光电流提高30%，但传统的背反射器由溅射金属薄膜组成。大规模生产溅射系统需要很高的资本成本和频繁的停机时间，因为系统维护和目标更换。除了成本高之外，用于纪录效率太阳能电池的银背反射器不能用于商业产品，因为附着力差，氧化和迁移到电池中，导致性能和可靠性下降。取而代之的是使用铝背反射器，但由于在阳光的最关键部分的反射率较差，只能导致适度的性能改进。该项目采用电泳沉积方法，使用新型溶液来生长介电纳米颗粒薄膜，这将降低生产背反射器的成本，因为减少了用于建造加工设施的资本支出，减少了停机时间，更有效地利用涂层材料，减少了能耗，从而降低了运营成本。为低价值表面添加高价值功能的技术存在广阔的市场机会，例如用于自清洁应用的超疏水表面涂层，用于光管理的光子结构，用于电子设备的纹理/多孔结构。获得高价值表面的传统方法通常需要化学湿法蚀刻、高真空和光刻方法，因此很少能走出实验室并成为商业上可行的产品。提出的创新是使用纳米颗粒为基础的薄膜，由低成本，“绿色”？可扩展的、与行业相关的电泳沉积方法，可以将增值技术推向市场。纳米颗粒薄膜的一个应用是太阳能电池的后反射器。有竞争力的太阳能技术需要高转换效率和低成本的制造技术。如果成功部署，该技术有望使太阳能制造商能够以更低的成本替代高真空溅射金属背反射器，以获得高效率和稳定的太阳能电池。

This I-Corps project aims to demonstrate the commercial viability of using highly reflective and light scattering nanoparticle thin films as solar cell back reflectors with the goal to replace high-vacuum processing techniques. Back reflectors can enhance the solar cells photocurrent by 30%, but conventional back reflectors consist of sputtered metal films. Large scale production sputtering systems require high capital cost and frequent downtime due to system maintenance and target replacement. In addition to the high cost, silver back reflectors used in record efficiency solar cells cannot be used in commercial products due to poor adhesion, oxidation, and migration into the cell resulting in deteriorated performance and reliability. Instead, aluminum back reflectors are used, but only results in moderate performance improvements due to poor reflectance in the most critical portion of sunlight. This project uses the electrophoretic deposition method using novel solutions to grow dielectric nanoparticle films, which will reduce the cost of producing back reflectors due to reduced capital expense devoted to building out the processing facilities and reduced operating expense through less down time, more efficient coating material utilization, and reduced energy consumption. A broad market opportunity exists for technologies that add high-value functionality to otherwise low-value surfaces, e.g. superhydrophobic surface coatings for self-cleaning applications, photonic structures for light management, textured/porous structures for electronic devices. Conventional methods to obtain high-value surfaces typically require chemical wet-etching, high-vacuum, and lithography methods, and consequently, rarely make it out of the lab and into commercially-viable products. The proposed innovation is to use nanoparticle-based films deposited by the low-cost, ?green?, scalable, and industry-relevant electrophoretic deposition method, which could bring value-added technologies to market. An application identified for the nanoparticle films is a solar cell back reflector. Competitive solar technologies require both high conversion efficiencies and low-cost manufacturing techniques. If successfully deployed, the proposed technology is expected to enable solar manufacturers a lower cost alternative to high-vacuum sputtered metal back reflectors for high efficiency and stable solar cells.