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Photoluminescence generated by substituting rare-earth ions on multiple crystallographically independent cation sites within a crystalline host material is one of the most common approaches for creating a full-spectrum phosphor-converted white light-emitting diode (pc-wLED). In this work, a series of complex orthophosphates with the composition (Sr8−xBax)0.99Eu0.08MgY(PO4)7 (x = 0, 1, 2, 3) were synthesized via high-temperature solid-state synthesis. These materials possess five potential substitution sites achieving broadband (5905 cm−1) yellow photoluminescence through multi-site substitution showing a violet-excited photoluminescent quantum yield of nearly 50%. Developing such an efficient broad emission spectrum is crucial for enhancing the color rendering ability of pc-wLEDs. Varying the Sr2+ to Ba2+ shifts the emission color from green-yellow to yellow under violet excitation (λex = 400 nm) while influencing the full-width-at-half-maximum (fwhm). Temperature-dependent photoluminescence measurements indicate that phosphor has good thermal stability with T50, the temperature at which the emission intensity is half of the low-temperature intensity, at 420 K and stable chromaticity coordinates, further supporting that the (Sr8−xBax)0.99Eu0.08MgY(PO4)7 series are promising candidates for LED white lighting. Constructing a prototype pc-wLEDs device using (Sr7Ba)0.99Eu0.08MgY(PO4)7, the highest quantum yield phosphor, produced a functional daylight bulb with a color rendering index (CRI) of 90.

IntroductionThe gold standard for diagnosis of active lupus nephritis (ALN), a kidney biopsy, is invasive with attendant morbidity and cannot be serially repeated. Urinary ALCAM (uALCAM) has shown high diagnostic accuracy for renal pathology activity in ALN patients.MethodsLateral flow assays (LFA) for assaying uALCAM were engineered using persistent luminescent nanoparticles, read by a smartphone. The stability and reproducibility of the assembled LFA strips and freeze-dried conjugated nanoparticles were verified, as was analyte specificity.ResultsThe LFA tests for both un-normalized uALCAM (AUC=0.93) and urine normalizer (HVEM)-normalized uALCAM (AUC=0.91) exhibited excellent accuracies in distinguishing ALN from healthy controls. The accuracies for distinguishing ALN from all other lupus patients were 0.86 and 0.74, respectively.ConclusionPeriodic monitoring of uALCAM using this easy-to-use LFA test by the patient at home could potentially accelerate early detection of renal involvement or disease flares in lupus patients, and hence reduce morbidity and mortality.

Identifying phosphors with good thermal stability and quantum efficiency is a prerequisite to improve the performance of white LED light sources. Here, a combined machine learning and density functional theory method is introduced to identify next generation inorganic phosphors.