Synthesis of YVO4:Eu3+ nanophosphors by the chemical coprecipitation method at room temperature

Room-Temperature and Ultrafast Synthesis of Highly Luminescent and Extremely Small Eu3+-Doped YVO4 Nanocrystals

“…To the best of our knowledge, there are no reports for sub-5 nm Eu 3+ -doped YVO 4 nanoparticles in the literature, and only Rivera-Enri ́quez et al have synthesized Eu 3+ -doped YVO 4 nanoparticles with an average size of 6 nm by a chemical coprecipitation approach. 18 Figure 2a,b shows the low-resolution transmission electron microscopy (LR-TEM) and high-resolution TEM (HR-TEM) images of Y 0.6 VO 4 :Eu 0.4 3+ nanocrystals. It was observed that the as-prepared nanoparticles are spherical, and their average particle size is 3.6 nm, which is smaller than the particle size determined by XRD (4.6 nm).…”

“…Rare-earth-doped metal oxide phosphors can emit light when they are exposed to various excitation sources, such as photons, electrons, X-rays, and electric fields. , These doped luminescent inorganic materials have been widely used in fluorescent lamps, cathode-ray tubes, X-ray detectors, field-emission displays, liquid-crystal displays, and plasma displays. , Rare-earth ions have a unique electron layer structure so that they have abundant electronic energy levels, which offer rich and colorful fluorescence properties. , Among rare-earth-doped metal oxide hosts, metal vanadate is considered as one of the most promising inorganic phosphors because of its strong light absorption in the ultraviolet region and high emission efficiency. − Yttrium vanadate (YVO 4 )-based phosphors exhibit high luminescence efficiency and excellent thermal and chemical stability, which are one of the most studied metal oxide-based phosphors. − In the past six decades, Eu 3+ -doped YVO 4 bulk phosphors have been extensively prepared by a high-temperature solid-state reaction, which requires a calcination temperature above 1000 °C for several hours. − In recent years, small-sized Eu 3+ -doped YVO 4 nanoparticles have received more and more attention due to their potential applications in high-resolution displays, drug delivery, and bioimaging …”

“…However, the photoluminescence quantum yields (PLQYs) of Eu 3+ -doped YVO 4 nanoparticles are significantly lower than 70% quantum yield for the corresponding bulk phosphor made by the high-temperature solid-state reaction, , resulting from low crystallinity and abundant surface defects of the small-sized nanocrystals . A number of methods for preparing Eu 3+ -doped YVO 4 nanocrystals have been reported, including microwave-assisted synthesis, Pechini method, hydrothermal reaction, − solvothermal reaction, coprecipitation method, spray pyrolysis, hydrolytic sol–gel route, and nonhydrolytic sol–gel process . It is important to note that the PLQYs of Eu 3+ -doped YVO 4 nanocrystals showed a big difference for different synthetic methods. − Yang et al prepared Eu 3+ -doped YVO 4 nanocrystals with different morphologies by a hydrothermal method using sodium citrate as the capping agent in a wide pH range, and the PLQY of litchi-like nanocrystals was as high as 55.5% .…”

“…A number of methods for preparing Eu 3+ -doped YVO 4 nanocrystals have been reported, including microwave-assisted synthesis, Pechini method, hydrothermal reaction, − solvothermal reaction, coprecipitation method, spray pyrolysis, hydrolytic sol–gel route, and nonhydrolytic sol–gel process . It is important to note that the PLQYs of Eu 3+ -doped YVO 4 nanocrystals showed a big difference for different synthetic methods. − Yang et al prepared Eu 3+ -doped YVO 4 nanocrystals with different morphologies by a hydrothermal method using sodium citrate as the capping agent in a wide pH range, and the PLQY of litchi-like nanocrystals was as high as 55.5% . Shen et al synthesized water-soluble Eu 3+ -doped YVO 4 nanoparticles with a PLQY of about 54% by a hydrothermal reaction .…”

“…Shen et al synthesized water-soluble Eu 3+ -doped YVO 4 nanoparticles with a PLQY of about 54% by a hydrothermal reaction . Although Eu 3+ -doped YVO 4 nanoparticles were synthesized at low temperatures, their quantum yields are much lower than that of the bulk phosphor. − Therefore, there is an urgent need to develop a room-temperature method for the rapid preparation of highly luminescent Eu 3+ -doped YVO 4 nanocrystals with a photoluminescence performance comparable to that of the bulk phosphor.…”