Dear Abdul Sattar,

The organic additive doping into a Perovskite layer within a perovskite solar cell proves an effective way of enhancing its performance. To work out the best doping concentrations, you had better to have various doping levels around the doping concentrations from references. In this way, you can optimise for your cells' performance.

If you use a new additive, you need to try a wide range of doping levels for your active layer to achieve the best performance. A lot of experiments need to be considered.

Xuhua Wang Thank you for your comprehensive opinion. However, I am curious if there is any rule of thumb to optimize concentration ratio, for example, the molar mass of the additive etc. to take into account before starting the experiment to minimize the number of experiments.

Hi Abdul Sattar

Firstly thank you Xuhua Wang for this opinion.

To perform the doping you need to choose a method that will help you get the desired product. Several methods are available in various literature. You have to choose a tunable method. The solution combustion method is very much helpful as it allows molecular level mixing of raw materials. There is no such thumb rule from the best of my knowledge but you may make a series of materials by varying the dopant concentration e.g., from 0 to 0.5, or 0, 0.1, 0.2, etc.

Regards

Dear Arnab Mukherjee,

Thank you for your opinion. This will surely help me to design my future experiments.

You should start from minimum amount and keep checking its physical properties, e.g., structural, morphological, and optical properties. Each time compare the results with the pristine one. Once you reach a limit, beyond which the properties are no more improving, will be your optimum value of the additive.

To start the optimization, initially you may consider few recent literatures to get an idea about a range of additive concentration. You may add particular amount of additives from a stock solution to a precursor solution of perovskite. For polymeric additives, the concentration may be required very less amount (0.1-1 mg/ml) and for small molecules it may be in the range of 1-10 mg/ml. So u can fabricate few opto-electronic devices (Photovoltaic/LEDs etc) and analyze the morphology of the perosvskite materials with wider range of additive concentration to select the optimum one with highest performance.

I am trying to add PEA as a spacer cation to form 2D perovskite structure in Formamidinium based perovskite solar cells. we can say the additive engineering on A site of absorber layer... Can anyone explain how to fix the n value practically? in literatures they have varied the n values as 1,2,3....10,20,......