Research On Devices Of Organic Solar Cells Based On Polymer

With high-speed development of economy all over the world, energy problem gives rise to regard of people more and more. The reduction of mineral fuel causes energy crisis and burning of mineral fuel causes greenhouse effect that makes existent environment of people face to great challenge. People have taken notice of solar energy that is over 99% of total energy on the earth, and solar energy has so many merits that many scientists have focused on them like as widest distribution and convenient acquisition, innocuity to persons and disbefouling environment, extremely excessive amount, et al. In this thesis, we aimed at material study of organic solar cells based on polymer, and carried through beneficial exploration in two aspects mainly:Firstly, coparative study on organic solar cells with different structures have been engaged. Two solar cells with the device structures of ITO / PEDOT:PSS / MEH-PPV/ C60 / Al and ITO / PEDOT:PSS / MEH-PPV:C60 / Al, in which poly 1,4-(2-methoxy-5-ethylhexyloxy) phenylenevinylene (MEH-PPV) is used as electron donors and fullerene (C60) is used as electron acceptors, were fabricated. Then the third device with the structure of ITO /PEDOT:PSS / PPV:C60 / C60 / Al was fabricated too. We compared the photovoltaic properties of these devices and found that short circuit density (JSC) of device 3 increases by about 300% and 150% than that of device 1 and device 2, respectively; open circuit voltage (VOC) increases by about 100% and 20%. The increased solar cell performance mostly can attribute to evaporating a layer of C60 to increase the amount of paths that electrons transfer from acceptor to cathode and enlarge the area of donor–acceptor interface. The other reason is that the C60 layer block the hole transfer from organics to cathode in some ways. Such change in structure of solar cells improves the performance of the solar cells effectively.