{"id":2892,"date":"2011-06-24T15:26:22","date_gmt":"2011-06-24T15:26:22","guid":{"rendered":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/?p=2892"},"modified":"2011-07-19T18:38:19","modified_gmt":"2011-07-19T18:38:19","slug":"ternary-mixtures-for-improved-performance-in-p3htpcbm-bulk-heterojunction-solar-cells","status":"publish","type":"post","link":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/ternary-mixtures-for-improved-performance-in-p3htpcbm-bulk-heterojunction-solar-cells\/","title":{"rendered":"Ternary Mixtures for Improved Performance in P3HT\/PCBM Bulk Heterojunction Solar Cells"},"content":{"rendered":"<div class=\"pf-content\"><p>Photovoltaic cells containing nanoscale phase separated mixtures of a poly(thiophene) donor and a fullerene acceptor in the active layer have proven to be a attractive class of low-cost solar energy harvesting devices. The benchmark polymer solar cell (PSC) is one fabricated with poly(3-hexylthiophene) (P3HT) and PC<sub>n<\/sub>BM (n = 61, 71, Figure 1), which displays power conversion efficiencies of approximately 5%<sup> [<a href=\"#footnote_0_2892\" id=\"identifier_0_2892\" class=\"footnote-link footnote-identifier-link\" title=\"G. Dennler, M. C. Scharber, and C. J. Brabec, &ldquo;Polymer-Fullerene Bulk-Heterojunction Solar Cells&rdquo; Adv. Mater., vol. 21, pp. 1323-1338, Nov. 2009.\">1<\/a>] <\/sup>. Extensive optimization of the polymeric donor component has lead to the evolution of PSCs with power conversion efficiencies of approximately 8%<sup> [<a href=\"#footnote_1_2892\" id=\"identifier_1_2892\" class=\"footnote-link footnote-identifier-link\" title=\"H.-Y. Chen, J. Hou, S. Zhang, Y. Liang, G. Yang, Y. Yang, L. Yu, Y. Wu, and G. Li, &ldquo;Polymer solar cells with enhanced open-circuit voltage and efficiency&rdquo; Nature Photon., vol. 3, pp. 649-653, June 2009.\">2<\/a>] <\/sup>; however, soluble fullerene derivatives remain the primary choice for the donor component in bulk heterojunctions. We have demonstrated that select small-molecule acceptors can serve as fullerene substitutes in P3HT\/PC<sub>61<\/sub>BM bulk heterojunctions and can increase the power conversion efficiencies of the resulting solar cells (Figure 2). Ternary mixtures containing 6,6-dicyanofulvenes<sup> [<a href=\"#footnote_2_2892\" id=\"identifier_2_2892\" class=\"footnote-link footnote-identifier-link\" title=\"T. L. Andrew, J. R. Cox, and T. M. Swager, &ldquo;Synthesis, Reactivity, and Electronic Properties of 6,6-Dicyanofulvenes&rdquo; Org. Lett. vol 12, pp. 5302-5305, Sept. 2010.\">3<\/a>] <\/sup>, such as DCF (Figure 1), yield average power conversion efficiencies of 4%. Moreover, ternary mixtures containing stable organic radicals, such as TEMPO and DPPH, also augment the performance of P3HT\u2013PC<sub>61<\/sub>BM solar cells and result in power conversion efficiencies of up to 3.4%.<\/p>\n\n\t\t<style type=\"text\/css\">\n\t\t\t#gallery-1 {\n\t\t\t\tmargin: auto;\n\t\t\t}\n\t\t\t#gallery-1 .gallery-item {\n\t\t\t\tfloat: left;\n\t\t\t\tmargin-top: 10px;\n\t\t\t\ttext-align: center;\n\t\t\t\twidth: 50%;\n\t\t\t}\n\t\t\t#gallery-1 img {\n\t\t\t\tborder: 2px solid #cfcfcf;\n\t\t\t}\n\t\t\t#gallery-1 .gallery-caption {\n\t\t\t\tmargin-left: 0;\n\t\t\t}\n\t\t\t\/* see gallery_shortcode() in wp-includes\/media.php *\/\n\t\t<\/style>\n\t\t<div id='gallery-1' class='gallery galleryid-2892 gallery-columns-2 gallery-size-medium'><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/06\/andrew_ternarymixtures_01-e1308929078110.jpg' rel=\"lightbox[2892]\"><img width=\"300\" height=\"226\" src=\"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/06\/andrew_ternarymixtures_01-300x226.jpg\" class=\"attachment-medium size-medium\" alt=\"Figure 1\" loading=\"lazy\" aria-describedby=\"gallery-1-2893\" srcset=\"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/06\/andrew_ternarymixtures_01-300x226.jpg 300w, https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/06\/andrew_ternarymixtures_01-e1308929078110.jpg 800w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-2893'>\n\t\t\t\tFigure 1: Structures of PC<sub>61<\/sub>BM, a soluble fullerene acceptor, and three substitutes for fullerene-based acceptors in polymer solar cells.\n\t\t\t\t<\/dd><\/dl><dl class='gallery-item'>\n\t\t\t<dt class='gallery-icon landscape'>\n\t\t\t\t<a href='https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/06\/andrew_ternarymixtures_02-e1308929108695.jpg' rel=\"lightbox[2892]\"><img width=\"300\" height=\"229\" src=\"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/06\/andrew_ternarymixtures_02-300x229.jpg\" class=\"attachment-medium size-medium\" alt=\"Figure 2\" loading=\"lazy\" aria-describedby=\"gallery-1-2894\" srcset=\"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/06\/andrew_ternarymixtures_02-300x229.jpg 300w, https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-content\/blogs.dir\/10\/files\/2011\/06\/andrew_ternarymixtures_02-e1308929108695.jpg 800w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a>\n\t\t\t<\/dt>\n\t\t\t\t<dd class='wp-caption-text gallery-caption' id='gallery-1-2894'>\n\t\t\t\tFigure 2: J-V characteristics of photovoltaic cells fabricated with ternary mixtures containing P3HT; 50 wt% PC<sub>61<\/sub>BM; and 50 wt% of either DCF, TEMPO, or DPPH.  \n\t\t\t\t<\/dd><\/dl><br style=\"clear: both\" \/>\n\t\t<\/div>\n\n<\/div><ol class=\"footnotes\"><li id=\"footnote_0_2892\" class=\"footnote\">G. Dennler, M. C. Scharber, and C. J. Brabec, \u201cPolymer-Fullerene Bulk-Heterojunction Solar Cells\u201d <em>Adv. Mater<\/em>., vol. 21, pp. 1323-1338, Nov. 2009. [<a href=\"#identifier_0_2892\" class=\"footnote-link footnote-back-link\">&#8617;<\/a>]<\/li><li id=\"footnote_1_2892\" class=\"footnote\">H.-Y. Chen, J. Hou, S. Zhang, Y. Liang, G. Yang, Y. Yang, L. Yu, Y. Wu, and G. Li, \u201cPolymer solar cells with enhanced open-circuit voltage and efficiency\u201d <em>Nature Photon<\/em>., vol. 3, pp. 649-653, June 2009. [<a href=\"#identifier_1_2892\" class=\"footnote-link footnote-back-link\">&#8617;<\/a>]<\/li><li id=\"footnote_2_2892\" class=\"footnote\">T. L. Andrew, J. R. Cox, and T. M. Swager, \u201cSynthesis, Reactivity, and Electronic Properties of 6,6-Dicyanofulvenes\u201d <em>Org. Lett. <\/em>vol 12, pp. 5302-5305, Sept. 2010. [<a href=\"#identifier_2_2892\" class=\"footnote-link footnote-back-link\">&#8617;<\/a>]<\/li><\/ol>","protected":false},"excerpt":{"rendered":"<p>Photovoltaic cells containing nanoscale phase separated mixtures of a poly(thiophene) donor and a fullerene acceptor in the active layer have&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[6,5528],"tags":[6134,6131],"_links":{"self":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/posts\/2892"}],"collection":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/comments?post=2892"}],"version-history":[{"count":3,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/posts\/2892\/revisions"}],"predecessor-version":[{"id":4019,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/posts\/2892\/revisions\/4019"}],"wp:attachment":[{"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/media?parent=2892"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/categories?post=2892"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mtlsites.mit.edu\/annual_reports\/2011\/wp-json\/wp\/v2\/tags?post=2892"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}