Lu₂CaMg₂(Si_1−xGe_x)₃O₁₂:Ce³⁺solid-solution phosphors: bandgap engineering for blue-light activated afterglow applicable to AC-LED

Abstract

Persistent luminescence (PersL) has long commanded the curiosity of researchers owing to the complicated and profound physics behind it. In this work, the PersL mechanism in a new kind of persistent garnet phosphors, Lu 2 CaMg 2 (Si 1Àx Ge x ) 3 O 12 :Ce 3+ , is studied from the new perspective of a ''solid-solution'' scheme. Different from the conventional study in pursuit of long PersL, we focus on manipulation of afterglow to the millisecond range and tentatively demonstrate its potential to compensate the flickering of the alternating current driven LED (AC-LED) in every AC cycle. Evidently, the tailored host bandgap favors efficient electron charging and facilitates electron detrapping, as well as redeploying trap distribution, which results in a blue light activated afterglow in the millisecond time range, and subsequently a reduced percent flicker of 64.1% for the AC-LED. This investigation is the first attempt to establish the design guidelines for new PersL materials with an adjustable millisecond ranged afterglow, and, hopefully, it paves a pathway to the development of burgeoning low-flickering AC-LED technology.

A Photostimulated BaSi2O5:Eu2+,Nd3+ Phosphor‐in‐Glass for Erasable‐Rewritable Optical Storage Medium

“…X‐ray diffraction (XRD) Rietveld refinement was conducted on a representative sample Ba 0.990 Eu 0.010 Si 2 O 5 , by employing the crystallographic data taken from the pure BaSi 2 O 5 (ICSD‐10 162) as the starting model ( Figure a). The reliability factors converge to χ 2 = 6.064, R wp = 4.32%, and R p = 3.12%, indicating that the refined atoms position, fraction factors, and temperature factors satisfy well with the reflection conditions . The main refined structural parameters are summarized in Table S1, Supporting Information.…”

Exploration of bluish violet‐emitting phosphor Ca3Al4ZnO10:Ti4+ with enhanced emission by Ca2+ vacancies

“…In addition, all decay curves can be well fitted by first‐order exponential decay model. This model can be illustrated by following equation:…”

A multicolor persistent luminescent phosphor Sr2Ga2GeO7:Pr3+ for dynamic anticounterfeiting

“…Owing to the unique property of “glow‐in‐the‐dark,” the PersL phosphors have attracted a widespread range of interests. Recently, PersL phosphors have been applied in various important fields, for example, the emergency lighting, optical storage, in vivo imaging, solar energy, and photocatalysis …”

“…Recently, PersL phosphors have been applied in various important fields, for example, the emergency lighting, optical storage, in vivo imaging, solar energy, and photocatalysis. [5][6][7][8] It is well known that a PersL phosphor consists of the host, emitters, and traps and the PersL color of a PersL phosphor usually depends on the emitters. Generally, the broadband emitters including d n TM and 5d-4f RE 3+ ions show the continuous emission bands in visible spectrum similar to the sunlight, and thus it is more suitable for lighting.…”