Check out the new publication from Emilia if you want to know more about the upconversion nanoparticle synthesis.

Palo, E., Tuomisto, M., Hyppänen, I., Swart, H.C., Hölsä, J., Soukka, T., and Lastusaari, M., “Highly uniform up-converting nanoparticles: Why you should control your synthesis even more”, J. Lumin. 185 (2017) 125–131.
Read online: http://dx.doi.org/10.1016/j.jlumin.2016.12.051

Have a look at our latest collaboration publications, from the end of 2016 and the beginning of 2017. One is about Mg doped AlGaN semiconductor crystals and its properties and the other about disintegration of upconverting nanoparticles.

Mäkelä, J., Tuominen, M., Nieminen, T., Yasir, M., Kuzmin, M., Dahl, J., Punkkinen, M., Laukkanen, P., Kokko, K., Osiecki, J., Schulte, K., Lastusaari, M., Huhtinen, H., and Paturi, P., Comparison of Chemical, Electronic, and Optical Properties of Mg-Doped AlGaN, J. Phys. Chem. C 120 (2016) 28591–28597.
Read online: http://dx.doi.org/10.1021/acs.jpcc.6b09248

Lahtinen, S., Lyytikäinen, A., Päkkilä, H., Hömppi, E., Perälä, N., Lastusaari, M., and Soukka, T., Disintegration of Hexagonal NaYF₄:Yb³⁺,Er³⁺ Upconverting Nanoparticles in Aqueous Media: The Role of Fluoride in Solubility Equilibrium, J. Phys. Chem. C 121 (2017) 656-665.
Read online: http://dx.doi.org/10.1021/acs.jpcc.6b09301