Plastic Solar Cells


Plastic Solar Cells - Technology, Challenges and Future Outlook

Vishal Shrotriya

Director, Technology Development

Solarmer Energy, Inc.


Polymer (or plastic) solar cells are today considered a promising candidate to provide clean, renewable and affordable power.  However, the efficiency of polymer solar cells is low and their stability is questionable, compared to their inorganic counterparts.  The photovoltaic conversion process in bulk-heterojunction polymer solar cells consists of the following steps:  light absorption by the active polymer, exciton generation in the polymer, charge separation at donor-acceptor interface, charge transport in donor and acceptor molecules and charge collection at the contacts.

One of the major challenges in achieving higher efficiency in OPVs is the lack of suitable absorber polymers with the required properties for a high efficiency device.  The major limitation from materials point of view is the inadequate absorption in the solar spectrum due to large band-gap of current absorber polymers.  In addition, non-optimized energy bands of donor polymer and acceptor fullerene molecules result in significant energy loss during charge separation.  Another challenge is the low charge carrier mobility of conjugated polymers compared to inorganic semiconductors, by several orders of magnitude.  This affects the charge transport in the active layer and charge collection at the polymer-metal interfaces.  To achieve high efficiency, polymers with broad absorption and high extinction coefficients are needed.  In addition, higher voltages can be reached if the energy levels of donor polymer and acceptor molecules are optimized.  Finally, better morphology control is required to increase the efficiency in polymer solar cells.  From the stability point of view, the lifetime of polymer solar cells is limited because of adverse effect of oxygen and moisture on the conjugated polymers.  As a result advanced encapsulation and barrier materials and processes are required to enhance the lifetime of polymer solar cells from currently demonstrated few thousand hours to more than 10 years of continuous usage under sunlight.  All this has to be done in a cost efficient way to make polymer solar cells an economically viable alternative to current inorganic solar cells.

In this talk we will focus on two aspects – increasing the efficiency of polymer solar cells by materials and device engineering, and enhancing the lifetime by advanced encapsulation materials and processes development.  We will outline the developments over the last decade and the current work being done in the industry and academia to push this technology towards commercialization.  We will also briefly cover potential applications and market opportunity for polymer solar cells.



Tuesday, April 21


Michael's Restaurant at Shoreline Park
2960 N Shoreline Blvd
Mountain View, CA  94043
Directions  Map


6 PM social hour
7 PM dinner
8 PM lecture





Early Registration - Up to 7 days in advance of deadline



Registration - Up to deadline



After deadline/walk-in (Availability NOT guaranteed)



Lecture-only is free.



we accept cash or checks, but are unable to accept payment by credit card at this time. You may pay at the door.


Please register on the web page or contact:
Len Radzilowski
email: lradzilo - at-


Deadline for registration:

5PM, Monday April 20 for registration
5PM, Monday April 13 for early registration discount.

Dinner Selections:

Salmon Filet
Chicken Portobello
Grilled Vegetable Brochette

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