In an article, The valence band maximum position and conduction band minimum position is calcaulted from UPS and UV-vis absorption. They have mentioned that their obtained value of VBM anad CBM is suitable for hole and electron speration. How can we conclude this? Is there any range given for VBM and CBM ? or any method to know the correct range for VBM and CBM ?
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Article Perovskite solar cells: An emerging photovoltaic technology