Synthesis of GdVO<SUB>4</SUB> : Bi,Eu red phosphor by combustion process

Abstract

The doubly doped (Bi3+ and Eu3+) GdVO4 powder is synthesized by the combustion of aqueous solutions containing metal nitrate (GdNO3), ammonium nitrate (NH4NO3), ammonium metavanadate (NH4VO3) and 3-methyl-5-pyrazole-5-one (3MP5O). The powders are mixed thoroughly by mechanical crushing for 1 h. The aqueous solution containing the redox mixtures, when rapidly heated at 400 &#176;C, ignite and undergo a self-propagating, gas-producing, exothermic reaction to yield fine particles of metal vanadate. The powder was calcined at 650 &#176;C for 1 h and washed with 1N HCl and NH4OH (30%) for several times. The formation of crystalline vanadates was confirmed by XRD, FTIR, and SEM techniques. Excitation and emission spectra were also recorded. A strong emission line at 619 nm due to the 5D0 &#8594; 7F2 transition in the red region was observed. The combustion solution route may be proposed as an economical technique for synthesizing red luminescent GdVO4 : Bi,Eu phosphor