White-Light Generation in Sr[sub 2]SiO[sub 4]:Eu[sup 2+], Ce[sup 3+] under Near-UV Excitation

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White-light emission is generated by combining blue and blue green to yellow emissions of Ce 3 + and Eu 2 + , respectively, in a single host lattice of Sr 2 Si O 4 . The excitation is in the near-UV region ( 350 – 370 nm ) . The role of concentration of Eu 2 + on the photoluminescence emission intensity in Sr 2 ‐ x Eu x Si O 4 [ x = 0.0025 , 0.005, 0.0075, and 0.01] is studied, and it is found that the critical concentration is 0.0025 mol . Energy migration over Eu 2 + sites occurs, resulting in concentration quenching. Ce 3 + exhibits a high absorption in the near-UV region. Energy transfer from Ce 3 + to Eu 2 + occurs in Sr 2 Si O 4 : Eu 2 + , Ce 3 + . Optimization of concentration of Eu 2 + to produce white light in Sr 1.98 ‐ x Eu x Ce 0.01 Li 0.01 Si O 4 shows that the optimum concentrations of Ce 3 + and Eu 2 + are 0.01 and 0.0025 mols , respectively. Partial energy transfer from Ce 3 + to Eu 2 + is responsible for the white-light generation. The results reveal that Sr 2 Si O 4 : Eu 2 + , Ce 3 + is an efficient “single host lattice phosphor” for solid-state lighting technology using UV light-emitting diode (LED) to generate white light.