Staniuk Malwina, Zindel Daniel, van Beek Wouter, Hirsch Ofer, Kränzlin Niklaus, Niederberger Markus, Koziej Dorota (2015), Matching the organic and inorganic counterparts during nucleation and growth of copper-based nanoparticles – in situ spectroscopic studies, in CrystEngComm
, 17, 6962-6971.
Deshmukh Rupali, Zeng Guobo, Tervoort Elena, Staniuk Malwina, Wood David, Niederberger Markus (2015), Ultrasmall Cu3N Nanoparticles: Surfactant-Free Solution-Phase Synthesis, Nitridation Mechanism, and Application for Lithium Storage, in Chemistry of Materials
, 27, 8282-8288.
Hirsch Ofer, Zeng Guobo, Luo Li, Staniuk Malwina, Abdala Paula M., van Beek Wouter, Rechberger Felix, Sueess Martin J., Niederberger Markus, Koziej Dorota (2014), Aliovalent Ni in MoO2 Lattice- Probing the Structure and Valence of Ni and Its Implication on the Electrochemical Performance, in CHEMISTRY OF MATERIALS
, 26(15), 4505-4513.
Staniuk Malwina, Hirsch Ofer, Kraenzlin Niklaus, Boehlen Rahel, van Beek Wouter, Abdala Paula M., Koziej Dorota (2014), Puzzling Mechanism behind a Simple Synthesis of Cobalt and Cobalt Oxide Nanoparticles: In Situ Synchrotron X-ray Absorption and Diffraction Studies, in CHEMISTRY OF MATERIALS
, 26(6), 2086-2094.
Kraenzlin N., Staniuk M., Heiligtag F. J., Luo L., Emerich H., van Beek W., Niederberger M., Koziej D. (2014), Rationale for the crystallization of titania polymorphs in solution, in NANOSCALE
, 6(24), 14716-14723.
Staniuk M., Niederberger M., Koziej D. (2014), Tracking of the Organic Species During the Synthesis of Cobalt-based Nanoparticles in Non-aqueous Solution, in NANOENGINEERING: FABRICATION, PROPERTIES, OPTICS, AND DEVICES XI
, 9170, 91700E-1-91700E-5.
The study of nanoparticle formation and growth under real synthesis conditions remains a fascinating and challenging objective. To replace time-consuming trial-and-error experiments in the laboratory by predictable and rationally planned synthesis strategies, it is absolutely essential to acquire a detailed mechanistic knowledge about nanoparticle formation from the dissolution of the precursor to the final material. In the case of nonaqueous syntheses, where the nanoparticles are prepared in organic solvents, an exhaustive reaction monitoring has to include the organic and the inorganic chemical reactions as well as the organic-inorganic interface. Such a complete process observation is only possible by simultaneously applying several characterization tools that provide complementary information about organic and inorganic species in the reaction solution.This application is a follow-up of a previous project called “Development of Concepts for the Size- and Shape Controlled Synthesis of Metal Oxide Nanoparticles in Surfactant-Free Reaction Systems”, SNF 200021_119741. The idea of that first project was to characterize not only the final inorganic nanoparticles, but also the organic by-products. Composition and concentration of the organic compounds in the final reaction solution did not only provide valuable information regarding possible chemical mechanisms involved in nanoparticle formation, but also gave some indication of their role in influencing particle size and shape. However, these studies were restricted to the ex-situ characterization of the final organic and inorganic compounds, which unfortunately still leaves room for speculations about the “real” chemical processes occurring in between the dissolution of the precursor and the precipitation of the nanoparticles. The only way to follow all stages of nanoparticle formation, i.e., chemical transformation of the precursor, nucleation and growth of nanoparticles, as well as the interaction of organic species with the surface of the nanoparticles, is to perform extensive in-situ studies that allow the simultaneous observation of the organic and inorganic processes and the investigation of the liquid-solid interface.To be able to retrieve the required information about both the organic and inorganic compounds, several in-situ probes will be applied. UV-vis spectroscopy will be used for the determination of band gap energies and thus for the calculation of the crystal size of semiconducting nanoparticles. Infrared (IR) spectroscopy mainly offers information about the organic compounds in solution. In combination with an attenuated total reflection (ATR) crystal, additionally the study of the solid-solution interface is possible. In particular, the surface chemistry of the nanoparticles can be analyzed, giving insight into the adsorption behaviour of organic species onto the nanoparticle surface with reaction time. Considering the deep influence of organic species on nanoparticle size and shape, such a tool is of irreplaceable value. Raman spectroscopy, on the other hand, provides information about organic and inorganic species, complementing the other two probes. If needed, the in-situ methods can be amended by selected ex-situ characterization techniques such as transmission electron microscopy (TEM) for particle morphology measurements, energy dispersive X-ray diffraction (EDX) for local determination of the chemical composition, selected area electron diffraction for the local structure analysis, and powder X-ray diffraction for bulk crystal structure analysis.Time- and temperature-dependent in-situ spectroscopic investigations will result in a full kinetic description of nanoparticle formation. Such data will be beneficial for the development of synthesis routes to doped and multi metal oxides, where the different chemical reactivities of the precursors represent a serious issue, leading to mixtures of binary metal oxides rather than to single-phase multi metal oxide compounds.