Influence of metal ion concentration in the glycol mediated synthesis of Gd2O3:Eu3+ nanophosphor

The solvothermal synthesis of highly luminescent and homogeneous Gd2O3:Eu3+ nanophosphor using diethylene glycol as medium, followed by controlled combustion with citric acid as fuel is reported. The influence of concentrations of carboxylic acid and metal cations on the structure, morphology and luminescence properties are investigated in detail. The microscopic investigations indicate the nanocrystalline nature and the strong influence of cation concentration on the size, shape and agglomeration of the particles. It is found that increase in concentration of metal cations lead to the reduction in agglomeration of nanophosphors. The large value of intensity parameter Ω2, suggested that Eu3+ ions reside in a more asymmetric environment, resulted in intense emission due to 5D0–7F2 electric dipole transition. Emission decay analysis of the samples exhibited one exponential nature. The samples prepared under optimum conditions showed a quantum efficiency of 78.63% and a moderately high life time of 1.217 ms.