The Influence of Medium on Fluorescence Quenching of Colloidal Solutions of the Nd<sup>3+</sup>: LaF<sub>3</sub> Nanoparticles Prepared with HTMW Treatment
Elena Timofeeva,
Elena Orlovskaya,
Alexandr Popov,
Artem Shaidulin,
Sergei Kuznetsov,
Alexandr Alexandrov,
Oleg Uvarov,
Yuri Vainer,
Gleb Silaev,
Mihkel Rähn,
Aile Tamm,
Stanislav Fedorenko,
Yurii Orlovskii
Affiliations
Elena Timofeeva
Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str. 38, 119991 Moscow, Russia
Elena Orlovskaya
Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str. 38, 119991 Moscow, Russia
Alexandr Popov
Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str. 38, 119991 Moscow, Russia
Artem Shaidulin
Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str. 38, 119991 Moscow, Russia
Sergei Kuznetsov
Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str. 38, 119991 Moscow, Russia
Alexandr Alexandrov
Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str. 38, 119991 Moscow, Russia
Oleg Uvarov
Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str. 38, 119991 Moscow, Russia
Yuri Vainer
Institute of Spectroscopy of the Russian Academy of Sciences, Fizicheskaya Str. 5, Troitsk, 108840 Moscow, Russia
Gleb Silaev
Higher School of Economics, National Research University, Myasnitskaya Str. 4, 101000 Moscow, Russia
Mihkel Rähn
Institute of Physics, University of Tartu, W. Ostwaldi Str. 1, 50411 Tartu, Estonia
Aile Tamm
Institute of Physics, University of Tartu, W. Ostwaldi Str. 1, 50411 Tartu, Estonia
Stanislav Fedorenko
Voevodsky Institute of Chemical Kinetics and Combustion SB RAS, Institutskaya Str. 3, 630090 Novosibirsk, Russia
Yurii Orlovskii
Prokhorov General Physics Institute of the Russian Academy of Sciences, Vavilov Str. 38, 119991 Moscow, Russia
An original method was proposed to reduce the quenching of the NIR fluorescence of colloidal solutions of 0.1 at. % Nd3+: LaF3 nanoparticles (NPs) synthesized by aqueous co-precipitation method followed by hydrothermal microwave treatment. For this, an aqueous colloidal solution of NPs was precipitated by centrifugation and dissolved in the same volume of DMSO. The kinetics of static fluorescence quenching of Nd3+ donors of doped NPs dispersed in two solvents was analyzed to determine and to compare the concentrations of OH- quenching acceptors uniformly distributed throughout the volume of the NPs. The dependences of the relative fluorescence quantum yield φ of colloidal solutions on the concentration of OH- groups in the NPs were calculated and were also used to determine concentration of acceptors in the volume of NPs in different solvents. It was found that the concentration of OH- groups in NPs dispersed in DMSO is almost two times lower than in NPs dispersed in water. This gives an almost two-fold increase in the relative fluorescence quantum yield φ for the former. The sizes of synthesized NPs were monitored by common TEM and by applying a rapid procedure based on optical visualization of the trajectories of the Brownian motion of NPs in solution using a laser ultramicroscope. The use of two different methods made it possible to obtain more detailed information about the studied NPs.
