Low-Voltage, Low-Waste Fabrication of Semiconducting Thin Films by Continuous Flow Electrophoretic Deposition

通过连续流电泳沉积低电压、低浪费地制造半导体薄膜

• 批准号: 1463412
• 负责人: Aaron Fafarman
• 金额: $ 30.6万
• 依托单位: Drexel University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1463412&HistoricalAwards=false
• 关键词: Low; Voltage; Waste; Fabrication; Semiconducting

One of the most significant impediments to the widespread use of solar energy is the manufacturing cost of the solar cell modules. Electrophoretic deposition, which uses an electric field to drive charged particles to a surface and which is scalable and low cost, presents a compelling solution to this manufacturing problem. This project will study electrophoretic deposition of inorganic semiconducting materials. The objective of this project is to electrophoretically deposit thin films from an ink comprised of nanometer-scale semiconductor crystals dispersed in a solvent. This research could lead to inexpensive, efficient, and sustainable processing methods for manufacturing solar cells from earth-abundant, non-toxic materials. The project will provide graduate and undergraduate students multidisciplinary training in cutting edge nanomanufacturing processes. The research results and accomplishments will be shared at public events, integrated into lectures and lab-based undergraduate courses and brought into the classrooms of a local public school. The objective of this project is to use colloidal, all-inorganic, nanocrystal dispersions in polar, non-aqueous electrolytes for low-voltage electrophoretic deposition. The hypothesis will be tested that the threshold voltage for electrophoretic deposition can be lowered by an order of magnitude to less than 1 volt under conditions in which electrolysis of the electrolyte is coupled with deposition of the electrophoresing particles. Such low voltages would lead to low deposition rates in conventional reactors. Therefore, a second hypothesis will be tested that continuously flowing the nanocrystal dispersion through an electrophoretic deposition microreactor can achieve both high deposition rate and thick films. Flow rate, reactor geometry, and applied bias can be tuned to achieve near-complete utilization of the nanocrystal feedstock and minimal waste generation. Work will focus on earth-abundant, non-toxic nanocrystals of copper zinc tin sulfide and lead sulfide, which have been used in the highest efficiency quantum dot solar cells. This research will deepen understanding of directed- and self-assembly processes under the influence of applied electric fields, focusing on the poorly understood, non-equilibrium behavior of chemically reactive ions at the intersection of bulk and nanoscale charged surfaces. Specifically it will probe the fundamental mechanism of electrophoretic deposition at low voltage.

广泛使用太阳能的最大障碍之一是太阳能电池模块的制造成本。电泳沉积使用电场将带电粒子驱动到表面，并且可扩展且成本低，为该制造问题提供了令人信服的解决方案。 本计画将研究无机半导体材料之电泳沉积。 本项目的目标是从由分散在溶剂中的纳米级半导体晶体组成的油墨中以电致存款方式沉积薄膜。这项研究可能会导致廉价，高效和可持续的处理方法，用于从地球上丰富的无毒材料制造太阳能电池。该项目将为研究生和本科生提供尖端纳米制造过程的多学科培训。研究成果和成就将在公共活动中分享，融入讲座和基于实验室的本科课程，并带入当地公立学校的教室。本项目的目的是使用胶体，全无机，分散在极性，非水电解质的低电压电泳沉积。将测试这样的假设，即在电解质的电解与电泳颗粒的沉积相结合的条件下，电泳沉积的阈值电压可以降低一个数量级至小于1伏。如此低的电压将导致传统反应器中的低沉积速率。因此，第二个假设将被测试，连续流动的电泳沉积微反应器的分散体可以实现高沉积速率和厚膜。可以调整流速、反应器几何形状和施加的偏压，以实现几乎完全利用废热处理原料和最小的废物产生。工作将集中在地球上丰富的，无毒的铜锌锡硫化物和硫化铅纳米晶体，这已被用于最高效率的量子点太阳能电池。这项研究将加深对施加电场影响下的定向和自组装过程的理解，重点是在大块和纳米级带电表面的交叉处化学反应离子的知之甚少的非平衡行为。具体而言，它将探讨在低电压下电泳沉积的基本机制。