Sintered cadmium telluride nanocrystal photovoltaics: Improving chemistry to facilitate roll-to-roll fabrication /

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Bibliographic Details
Author / Creator:Kurley, James Matthew, III, author.
Ann Arbor : ProQuest Dissertations & Theses, 2016
Description:1 electronic resource (160 pages)
Format: E-Resource Dissertations
Local Note:School code: 0330
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Other authors / contributors:University of Chicago. degree granting institution.
Notes:Advisors: Dmitri V. Talapin Committee members: Phillipe Guyot-Sionnest; Luping Yu.
Dissertation Abstracts International, Volume: 78-06(E), Section: B.
Summary:Recent interest in clean, renewable energy has increased importance on cost-effective and materials efficient deposition methods. Solution-processed solar cells utilizing cadmium telluride nanocrystal inks offer a viable method for reducing cost, increasing materials effectiveness, and decreasing the need for fossil fuels in the near future. Initial work focused on developing a useful platform for testing new chemistries for solubilizing and depositing nanocrystal inks. Layer-by-layer deposition using a combination of spincoating, cadmium chloride treatment, and annealing created a photovoltaic-grade CdTe absorber layer. In conjunction with layer-by-layer deposition, a device architecture of ITO/CdTe/ZnO/Al was utilized to create power conversion efficiencies of over 12% with the help of current/light soaking. Detailed exploration of device geometry, capacitance measurements, and intensity- and temperature-dependent testing determined the ITO/CdTe interface required additional scrutiny. This initial investigation sparked three new.
avenues of research: create an Ohmic contact to CdTe, remove the cadmium chloride bath treatment, and create a roll-to-roll friendly process. Improved contact between ITO and CdTe was achieved by using a variety of materials already proven to create Ohmic contact to CdTe. While most of these materials were previously employed using standard approaches, solution-processed analogs were explored. The cadmium chloride bath treatment proved inconsistent, wasteful, and difficult to utilize quickly. It was removed by using trichlorocadmate-capped nanocrystals to combine the semiconductor with the required grain growth agent. To establish roll-to-roll friendly process, the deposition method was improved, heating source changed, and cadmium chloride bath step was removed. Spraycoating or doctor-blading the trichlorocadmate-capped nanocrystals followed by annealing with an IR lamp established a process that can deposit CdTe in a high throughput manner.