fDear Sindhu hs

For doping in ZnO by spray pyrolysis method wt% is more used and suitable method

You can dope in wt% as well as in at%, but you need to investigate phase of ZnO for any percentage of doping,  Higher doping in any percentage will generate dopant phase in ZnO. 

As per my experience, at% doping is more stable doping and to avoid dopant phase formation. Second thing, your film quality, grown by spray pyrolysis,  would be more stable as compared to wt% doping films.  

Dear Sindhu hs

For doping in ZnO, volumetric percentage of doping solution with different molar concentration is more beneficial in main precursor base material solution in case of spray pyrolysis. It is convenient that you can make same molarity of doping and base material precursor solution. There are three important parameters.1) Volumetric percentage of both doping and precursor solution,2) Spray rate,3) deposition time 4) substrate temperature. You can very any two by keeping  other two constant. If you choose these method you can develop good uniformly deposited film with good surface morphology which is beneficial to further investigation and application.

Good luck and Best wishes

S.B.Deshmukh

How to calculate the at% and wt% for the above mentioned dopant. Is there any fixed formula.

Thanks

Dear Sindhu,

You can use the x % of the Zn concentration in solution. To adjust the doping ratio, you should change the x value. In our previous studies, we have doped indium sulfide by silver in spray pyrolysis technique. In that studies, we have used the atomic percent of the In concentration in solution (0.5 to 10 %). If you like to learn more, you can explore the following articles.

All the best.

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