Nanoparticles exhibit unique physical properties that are not found in their bulk counterpart. The synthesis
structure which contains Au or Ag core metallic particles and a shell of CdSe semiconductor has the combined properties
of quantum dots and the metallic particles. A new method has been developed to grow plasmonic semiconductor
nanocomposites of Au/CdSe and Ag/CdSe nanostructure. The method based on preparing seed of metal nanoparticles
which used as a seed using organometllic pyrolysis followed by adding the semiconductor precursors. Their chemical
composition crystal structure is determined via X-Ray Diffraction. The collective optical properties of the plasmonic
semiconductor nanohybrid has been measured using spectrophotometer techniques and compared to those individual
components. The main features which observed in the hybrid nanostructure is broodning of Plasmonic band and decrease
in its amplitude in addition to shifting excitonic energy band to higher wave length.The quenching of the emission of
Au/CdSe has been observed due to photoinduced electron injection into metallic seed. The electron transfer processes from
CdSe to the gold is more faster than that of the silver. For this reason, we can consider the CdSe/Au is strong plasmonic -
exitonic coupling but CdSe/Ag is week plasmonic-excitonic coupling.