It's allways a good idea to write what you have measured and where. Remember, this might be crucial information in the search for an answer.
sir i have read that if ir rays falls on photodiode then there is change in voltage .
When light falls on it, it will allow a larger flow of electrons.
There will be voltage around 1v bt when light falls it begin to conduct & the voltage will be around 5v this is not happening with me in this circuit if i am wrong then plz correct me & tell me any other method to check whether it is wrking or not.
Your circuit is not for what I think you wanna do. If you're trying to measure with a DMM on the output (marked "To ADC0"), you'll get 0V on DC, light or not, as DC and slow changes won't register as you have it coupled through a capacitor (C2).
If you measure on the other side of C2, what happens then?