title: Strong stokes and upconversion luminescence from ultrasmall Ln(3+)-doped BiF3 (Ln=Eu3+, Yb3+/Er3+) nanoparticles confined in a polymer matrix.
abstract: Heavy metal fluorides like BiF3 as a host for lanthanide ions are of interest as bismuth is the only heavy metal that is nontoxic. In this work, we report the synthesis of highly water-dispersible ultrasmall BiF3 nanoparticles about 6 nm in size within a poly(vinyl pyrrolidone) matrix by a hydrothermal method. Microscopy analysis reveals that the nanoparticles are well separated and confined within the polymer network. These nanoparticles were found to be excellent hosts for lanthanide (Ln(3+)) ions. Through suitable Ln(3+) doping, BiF3 exhibits strong emissions in the visible region upon both UV and near infrared (NIR) excitations. The non-toxicity of both bismuth and PVP can be advantageous for the potential use of BiF3 nanoparticles in drug delivery and bioimaging.
authors.affiliation: Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER)-Kolkata, Mohanpur Campus, Nadia district, WB 741252 (India), Fax: (+91) 33-25873020.
authors.forename: Shyam
authors.initials: S
authors.lastname: Sarkar
authors.forename: Armita
authors.initials: A
authors.lastname: Dash
authors.forename: Venkataramanan
authors.initials: V
authors.lastname: Mahalingam
mesh_terms: D001729:Bismuth / Q000737:chemistry*; D004871:Erbium / Q000737:chemistry; D005063:Europium / Q000737:chemistry; D005459:Fluorides / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D011205:Povidone / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water / Q000737:chemistry; D015018:Ytterbium / Q000737:chemistry
chemical_list: D007477:Ions; D028581:Lanthanoid Series Elements; D014867:Water; D005063:Europium; D004871:Erbium; D011205:Povidone; D015018:Ytterbium; D005459:Fluorides; D001729:Bismuth
keywords: bismuth fluoride; hydrophilic; lanthanides; nanoparticles; upconversion