Single Atom Silver-Phosphors in Titanosilicate Matrix for Enhanced LED Applications

Small metal oligomers have gained significant attention due to their exceptional optoelectronic properties and versatile applications, ranging from sensors to imaging and catalysis. However, the need for matrices (silica, zeolites, or metal-organic frameworks) to prevent aggregation into larger metallic particles reduces their potential applicability in light-emitting devices (LEDs) due to their poor electrical properties. To address this issue, a novel semiconductor stabilizer, titanosilicate, is proposed as an innovative solution for Ag-based luminescent materials. These results show that titanosilicate, characterized by high thermochemical stability and well-defined semiconducting properties, is an ideal scaffold for Ag-luminescent species. Optical spectroscopic techniques reveal that Ag-titanosilicates feature an orange fluorescence with a photoluminescence quantum yield reaching 20%. In contrast, a combination of X-ray diffraction, TEM, and XEOL-X-ray absorption spectroscopic techniques show that, unlike zeolites, the luminescent species consist of single Ag atoms. The electroluminescent properties of the proposed Ag-titanosilicate are further investigated within a conventional LED architecture by using the new material as an emissive layer. The developed proof-of-concept LED exhibits a significant improvement of the ZEOLEDs, where a smaller low turn-on voltage of 2 V (enabling energy-efficient operation) and high color rendering index of 80 introduces exciting prospects for developing advanced Ag-LED phosphors. Small metal oligomers with exceptional optoelectronic properties have applications in sensing, imaging, and catalysis. However, stabilizing matrices like glasses or zeolites limits their application in light-emitting devices (LEDs) due to poor electrical properties. Here, a titanosilicate is proposed as a stabilizer for Ag-based luminescent materials, providing a stable scaffold for Ag species with high quantum yield and featuring single Ag atoms, making it a promising solution for LEDs.image