Carrier Formation Dynamics of Organic Photovoltaics as Investigated by Time-Resolved Spectroscopy

<table>Molecular structures of poly(3-hexylthiophene) (P3HT), poly(9,9′-dioctylfluorene-co-bithiophene) (F8T2), <svg height="14.85" id="M9" style="vertical-align:-2.22495pt" version="1.1" viewbox="0 0 34.887501 14.85" width="34.887501" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg>-phenyl C<sub>61</sub>-butyric acid methyl ester (PCBM), and <svg height="14.85" id="M10" style="vertical-align:-2.22495pt" version="1.1" viewbox="0 0 34.887501 14.85" width="34.887501" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,0,0,-.017,.062,12.013)"><path d="M290 -163h-170v866h170v-28q-79 -7 -94 -19.5t-15 -72.5v-627q0 -59 14.5 -71.5t94.5 -19.5v-28z" id="x5B"></path></g><g transform="matrix(.017,0,0,-.017,5.927,12.013)"><path d="M137 343l67 33q37 17 63 17q79 0 129.5 -53t50.5 -131q0 -92 -58 -156.5t-147 -64.5t-147 68t-58 182q0 63 17 119t43 95.5t61.5 72t69 52t67.5 31.5q62 22 128 33l6 -32q-56 -11 -108 -35q-149 -71 -184 -231zM227 337q-47 0 -95 -27q-6 -23 -6 -70q0 -93 36 -155.5
t96 -62.5q53 0 78 45.5t25 105.5q0 68 -35 116t-99 48z" id="x36"></path></g><g transform="matrix(.017,0,0,-.017,14.086,12.013)"><path d="M95 130q31 0 61 -30t30 -78q0 -53 -38 -87.5t-93 -51.5l-11 29q77 31 77 85q0 26 -17.5 43t-44.5 24q-4 0 -8.5 6.5t-4.5 17.5q0 18 15 30t34 12z" id="x2C"></path></g><g transform="matrix(.017,0,0,-.017,20.784,12.013)"><path d="M137 343l67 33q37 17 63 17q79 0 129.5 -53t50.5 -131q0 -92 -58 -156.5t-147 -64.5t-147 68t-58 182q0 63 17 119t43 95.5t61.5 72t69 52t67.5 31.5q62 22 128 33l6 -32q-56 -11 -108 -35q-149 -71 -184 -231zM227 337q-47 0 -95 -27q-6 -23 -6 -70q0 -93 36 -155.5
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</svg>-phenyl C<sub>71</sub>-butyric acid methyl ester (PC<sub>70</sub>BM).</table>

Advances in Optical Technologies

fig1

Figure 1

Figure 1: Carrier Formation Dynamics of Organic Photovoltaics as Investigated by Time-Resolved Spectroscopy 