I am working on perovskite solar cells. In many papers i have found that the electron affinity and band gap is changed in simulation study. But normally electron affinity and band gap is constant for any particular material. Can anyone please explain this to me????
Thanks in advance.
As the bandgap is dependent on the temperature of operation according to the Varshni equation, therefore at the time of analysis if the temperature is different then of course you can change it.
Another reason for the change might be the composition variation of different elements in the compound you are using.
Thank you Gaurav Siddharth sir, bt few papers based on simulations have shown the effect of change in electron affinity on the efficiency by plotting the graph between the two. Can we plot such graphs while making the simulation study/investigation.
If electron affinity changes then it will also change the efficiency because the change in affinity leads to the change in the conduction band and valence band offset of the p-n junction.
Yes, you can make those graphs in the simulation study. I don't know whether you will be able to make them directly in the software only or you have to make them indirectly by varying the value of electron affinity step by step and keeping the note of efficiency for every affinity. I think Brajendra S. Sengar will guide you better in this regard. As he has mastery of the simulation.
Brajendra S. Sengar please help if possible.
Romana Yousuf, you can change the bandgap of material in the simulation tool but it is meaningful only if it is possible to fabricate that material (bandgap). For example, in case of Si (Not possible to fabricate Si with bandgap variation), it is not advisable to change the bandgap in the simulation tool. However, for CZTSSe you can have the bandgap variation by changing S, Se composition then you can have the plot of bandgap variation with efficiency in SCAPS for CZTSSe.
The same goes for electron affinity as well.
Dear Romana Yousuf
An article entitled "Influence of affinity, band gap and ambient temperature on the efficiency of CIGS solar cells" have full informative materials about your query definitely it will give complete insight about it
- Badges
- Science topic