▎ 摘　　要

NOVELTY - Alkali or alkaline earth metal-lanthanide-fluoride-graphene oxide nanocomposite (I) is new. The nanocomposite is photoluminescent. USE - The nanocomposites are useful in both photonic and biophotonic applications, where the photonic applications include efficient white light emitting materials, quantum-cutting phosphors for energy efficient and environmentally benign lighting and plasma display applications, upconversion materials and solar cells, and the biophotonic applications include photodynamic therapy, fluorescence resonance energy transfer based and other biological detections, in vivo and in vitro imaging. ADVANTAGE - (I) can be prepared by using a simple and economical one pot process. DETAILED DESCRIPTION - Alkali or alkaline earth metal-lanthanide-fluoride-graphene oxide nanocomposite of formula (M1nL1mF1p:R1,R2q-G1) (I) is new. The nanocomposite is photoluminescent. M1 = alkali metal or alkaline earth metal; n, m, q = 0-1; L1 = lanthanide; F1 = fluoride; p = 2-5; R1 = first/only rare-earth dopant ion; and R2 = second rare-earth dopant ion, where m and n cannot be zero simultaneously. INDEPENDENT CLAIMS are also included for: (1) photoluminescent nanocomposite (c2) comprising barium fluoride-cerium(III)/terbium(III)-graphene oxide, lanthanum trifluoride-cerium(III)/terbium(III)-graphene oxide, cerium trifluoride-terbium(III)-graphene oxide and gadolinium trifluoride-terbium(III)-graphene oxide, where the dopant ion cerium(III) and terbium(III) concentration is 1% of the inorganic matter excluding graphene oxide; and (2) preparing (I).