Development of the Novel Hybrid Nanowire-based Solar Cell on a Flexible Substrate
EMSL Project ID
30500
Abstract
Since the worlds oil and other fuel resources are finite and depleting, great interests have been focused towards finding alternative energy sources. Among the contenders competing to replace fossil fuels, solar cells offer many advantages including being low-maintenance and environmentally-benign. Solar cells already have a great number of applications in addition to the potential for many more, particularly in the energy, communications, military and space industries. The major drawbacks of solar cells to date have been cost and performance (power conversion efficiency). Solar radiation is a plentiful and clean source of power, but because of the high cost of electrical conversion using conventional solar cells, it has been exploited to its full potential when measured on a per watt basis. Hybrid organic-inorganic solar cells showed a possibility of fabricating solar cells with low-cost but they are still facing with a problem with low power conversion efficiency. One of the reasons for the low quantum efficiencies is attributed to the poor transport of charges. The poor transport of charges can be resulted from phase separation in the composite films. Alivisatos et al. proposed that as the aspect-ratio of the nanorods increases from 1 to 10, the charge transport must improve substantially to yield an external quantum efficiency (EQE) enhancement by a factor of approximately 31. Therefore in order for plastic nanorod devices to achieve typical power conversion efficiencies to conventional inorganic solar cells, it is necessary to reduce charge recombination, which decrease the EQE at solar light intensities. Further enhancement of carrier mobilities can be accomplished by improving the nanocrystal-polymer interface to remove nanorod surface traps, aligning the nanorods perpendicular to the substrate, and further increasing their length. However, the colloidal chemistry used for preparing alongated nanocrystals has a limitation of fabricating high aspect-ratio nanocrystals. Hybrid organic-inorganic solar cells based on nanowires have several advantages over the other types of solar cells: (1) Absorption of lights having a wide range of wavelengths,
(2) Increased carrier mobilities in organic matrix ,
(3) Low cost process compatible with Roll-to-Roll process
We will combine our novel nanowire fabrication process and conventional microfabrication process for fabricating next generation solar cell devices.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2008-08-22
End Date
2009-09-30
Status
Closed
Released Data Link
Team
Principal Investigator