Electrical Transport in Photodiodes

5 Nanostructure in Polymer/Molecule and Polymer/Polymer Blends 

POMeOPT+Ceo (1 1) blends spin-coated onto ITO/glass substrates 

A different combination of blend and bilayer structures can also be quite efficient. Having a mixture of polymers in the donor layer and using Ceo as the acceptor provides a way of increasing the spectrai range of absorption of photovoltaic cells while retaining good collection efficiency [23]. A blend donor layer can also be used to mimic the process of photosynthesis where many 

It was shown earlier that the efficiency of the diode depends significantly on the thicknesses of the layers due to the optical field distribution inside the device, caused by the interference of the incoming light with light reflected from the mirror cathode. The blend diode is always more efficient than the neat diode. The excitation created by absorption in the PPV phase is transferred to the polythiophene, where a more efficient charge separation process is possible, as is clear from Figs. 6.10 and 6.11. 

We have also studied photodiodes with the polymer blend (BEHP-PPV polythiophene) but without Ceo- We find very small photocurrents and no ev- 

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