论文部分内容阅读
White light-emitting diodes (W-LEDs) have attracted persistent attention in recent decades due to their magnificent advantages [1].During the development of W-LEDs, one of the major concern problems is the degradation of epoxy resins which will lead to the chromatic aberration and poor white light performance.In this context,Glasses as novel durable materials, possessing excellent optical properties, flexibility of size and shape as well as epoxy resin-free in assembly process, have been investigated extensively for W-LEDs.Among the various luminescent glasses, rare-earth (RE)-free materials with tunable luminescence have been explored as potential candidates for lighting sources considering the high cost and uncertainty about the stable supply of RE.Transition metal Mn2+ emission is typically a broad band, related to d-d transition and strongly field-dependent.Since the absorption efficiency of d-d transition is low due to the spin-and parity-forbidden electric dipole transition, sensitizers are often utilized to enhance the absorption of Mn2+ by means of energy transfer (ET).Recently, molecule-like Ag (ML-Ag) clusters have been presented as a fascinating new class of sensitizers.These clusters possess discrete ML energy band structures, and thus exhibit unique luminescent properties.Moreover, to the best of our knowledge, no report has been carried out on the pumping of Mn2+ by ML-Ag through ET to generate white luminescence.In this paper, Ag clusters/Mn2+ codoped zinc-borate glasses were first prepared by melt-quenching technique.The luminescent properties and ET process were investigated systematically.Tunable emissions from green through white to red can be achieved.Our results suggest that Ag clusters/Mn2+ codoped glasses may be used as converting phosphors for UV-excitation W-LEDs.