Why additives are used in organic solar cells? Do they really participate in enhancing the performance? Don't they go off during drying or annealing? How their existence can be ensured after these process?
There are two types of additives nonvolatile and volatile with the volatile additives cause normally instability in the solar cells. So, the additives must be of the solid sate type. The additive are used to improve the distribution of the donors and acceptors in the Donor-Acceptor blend. Such distribution plays a very important role in the conversion efficiency of the solar cell. It is said that the additives control the morphology of the mix. Other types of additives such as plasmons in the transport layers leads to enhancing their conductivity and reducing their resistance for the current transport.
You can search the web for effect of additives on the performance of the organic solar cells.
There are two types of additives nonvolatile and volatile with the volatile additives cause normally instability in the solar cells. So, the additives must be of the solid sate type. The additive are used to improve the distribution of the donors and acceptors in the Donor-Acceptor blend. Such distribution plays a very important role in the conversion efficiency of the solar cell. It is said that the additives control the morphology of the mix. Other types of additives such as plasmons in the transport layers leads to enhancing their conductivity and reducing their resistance for the current transport.
You can search the web for effect of additives on the performance of the organic solar cells.
Prof. Zekry comment covers most of your questions in a very professional way.
Regarding the existence confirmation of the additive in the active layer after fabrication, you can examine it via depth-profile X-ray photoelectron spectroscopy (DP-XPS). Also, the secondary ion mass spectrometry (SIMS) depth-profile is another more accurate technique used to confirm the elements existence through the active layer depth. You can either test the OPV full device or the active layer only.
You can check the web, it is full of reviews related to OPVs morphology control and characterization.
Organic photovoltaic (OPV) solar cells aim to provide an Earth-abundant and low-energy-production photovoltaic (PV) solution. This technology also has the theoretical potential to provide electricity at a lower cost than first- and second-generation solar technologies. Because various absorbers can be used to create colored or transparent OPV devices, this technology is particularly appealing to the building-integrated PV market. Organic photovoltaics have achieved efficiencies near 11%, but efficiency limitations as well as long-term reliability remain significant barriers.