1. Update 3 April 29, 2010 JESUS GUARDADO, LEAH NATION, HUY NGUYEN, TINA RO

2. Agenda Project Background What's New Results Problems & Analysis Changes Future Plans Flexible Cell http://www.worldofrenewables.com

3. Project Background Polymeric Photovoltaic Cells o Low fabrication costs o Fast processing speed o Light weight o Flexible Single Walled Carbon Nanotubes o Aid transfer of electrons o Improve Voc, Jsc o $8 per m2 swCNTs at 80,000x SWeNT SG 65, from CoMoCAT

4. Cell Design FTO - Fluoride Tin Oxide PEDOT - Poly(3,4-ethylenedioxythiophene) P3HT - poly(3-hexylthiophene)

5. Fabrication & Testing Created samples: o 3 solutions => 6 samples o 0, 3.75, 6 wt% CNT o Spin-coated onto substrates o Deposited electrode o 1 sample => 4 devices Testing o O.N.E. Lab's equipment o I-V curves o Voltmeter  Open circuit potential  No light vs desk lamp Samples Devices with testing probes

6. Sample 1 (0% CNT) LocationWithout Light (mV)With Light (mV) 1-- 2 3 4165312 Sample 4 (6% CNT) LocationWithout Light (mV)With Light (mV) 1125275 2-- 3133310 482198 Results: Photoresponse

7. Results: IV Curves Resistor-like o resistor = centered at 0V Not diode o no p-n junction o electrons + holes go both ways Some samples had no response IV Curve of Sample 1 - Location 4

8. Variables

9. Troubleshooting

10. Variables & Round 3

11. Modifications for Round 3 Changes Smaller fabrication-testing window Use 1% wt and 2% wt CNTs Increase P3HT:DCB to 10mg/mL Why? Same as previous studies o Geng & Zeng (2006) o Liu et al. (2008) www.mse.edu

12. Current Progress & Future Schedule

13. Thank you. Questions? You may reach us at nanosol@mit.edu http://web.mit.edu/course/3/3.042/team1_10

14. Results: I-V Curves Sample Result Desired Diode Curve