It is interesting to note in recent years for a large number of researchers the topic of photonic crystals (PhCs) because of their new and useful properties. In addition, there are many advantages to photonic crystals materials as a high reflectance materials as well as the high transmittance materials based on the target application. The calculations were done for Aluminum oxide and titanium oxide (Al2O3/TiO2) composite photonic crystal in one dimension, which shows a high reflectivity (~ 99 %). The chosen photonic crystal composite can be useful to reflect the Cherenkov light many times which comes out from Cherenkov radiation by using radioisotope 90Sr-90Y. The output intensified light has power 1.45 µwatt and 1.45 nwatt for 90Sr-90Y with the activity 1Ci and 1mCi respectively, that can be used for micro/nano-power source applications.