{"66412":{"#nid":"66412","#data":{"type":"event","title":"MSE PhD Defense Presentation \u2013 Jack Flicker","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003ETitle\u003C\/strong\u003E:\u0026nbsp;Three-Dimensional Carbon Nanotube Based Photovoltaics\u003C\/p\u003E\n\n\n\n\u003Cp\u003E\u003Cstrong\u003ESUMMARY\u003C\/strong\u003E: Photovoltaic (PV) cells with a three dimensional (3D) morphology are an\nexciting new research thrust with promise to create cheaper, more efficient\nsolar cells. This work introduces a new type of 3D PV device based on\nvertically aligned carbon nanotube (CNT) arrays. These arrays are paired with\nthe thin film heterojunction, CdTe\/CdS, to form a complete 3D PV device\n(3DCNTPV).\u0026nbsp;\u003C\/p\u003E\n\n\u003Cp\u003EThe main benefit of the 3DCNTPV cell is the ability to utilize\nmultiple photon interactions with the solar cell surface. This three\ndimensionality allows photons to interact multiple times with the photoactive\nmaterial, which increases the absorption and the overall power output over what\nis possible with a two dimensiona (2D) morphology. To quantify the increased\npower output arising from these multiple photon interactions, a new absorption\nefficiency term,\u0026nbsp;h\u003Csub\u003E3D\u003C\/sub\u003E, is introduced. The\ntheoretical basis behind this new term and how it relates to the absorption\nefficiency of a planar cell,\u0026nbsp;h\u003Csub\u003E2D\u003C\/sub\u003E, is derived. \u0026nbsp;This theory is validated by monte carlo\nsimulations.\u003C\/p\u003E\n\n\u003Cp\u003EA series of 3DCNTPV prototype cells was developed.\u0026nbsp;Marriage\nof a complicated 3D structure with production methods traditionally used for\nplanar CdTe solar cell is challenging. This work examines the problems\nassociated with manufacturing these types of cells and systematically alters\nproduction methods and architecture of the semiconductor layers and electrodes\nto increase the short circuit current (I\u003Csub\u003Esc\u003C\/sub\u003E), eliminate parasitic\nshunts, and increase the open circuit voltage (V\u003Csub\u003Eoc\u003C\/sub\u003E).\u0026nbsp;\u0026nbsp;Original\nprototype cells suffered from very low power output.\u0026nbsp;\u0026nbsp;I\u003Csub\u003Esc\u0026nbsp;\u003C\/sub\u003Eand\u003Csub\u003E\u0026nbsp;\u003C\/sub\u003EV\u003Csub\u003Eoc\u0026nbsp;\u003C\/sub\u003Ein\nlater cells\u003Csub\u003E\u0026nbsp;\u003C\/sub\u003Ewas increased\u0026nbsp;by an order of magnitude and\n300%, respectively.\u0026nbsp;Output power of the 3DCNTPV cells\u0026nbsp;was\nmeasured\u0026nbsp;at varying incident angles of light and these cells show an\nincrease in the normalized power output compared to similar planar cells when\nthe solar flux is at off-normal angles. Experimental power output vs. zenith\nangle of the 3DCNTPV cells shows very good agreement with the theory proposed\nin this work.\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003E\u0026nbsp;Title:\u0026nbsp;Three-Dimensional Carbon Nanotube Based Photovoltaics\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"MSE PhD Defense Presentation \u2013 Jack Flicker"}],"uid":"27388","created_gmt":"2011-06-07 14:49:57","changed_gmt":"2016-10-08 01:55:08","author":"Bill Miller","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2011-06-15T11:00:00-04:00","event_time_end":"2011-06-15T13:00:00-04:00","event_time_end_last":"2011-06-15T13:00:00-04:00","gmt_time_start":"2011-06-15 15:00:00","gmt_time_end":"2011-06-15 17:00:00","gmt_time_end_last":"2011-06-15 17:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"1238","name":"School of Materials Science and Engineering"}],"categories":[],"keywords":[{"id":"10802","name":"MSE_Interal_Event"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1791","name":"Student sponsored"}],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[],"email":[],"slides":[],"orientation":[],"userdata":""}}}