Date of Award
Development of novel materials with sought after properties has been the forefront in the field of nanomaterials. Hybrid nanomaterial architectures, or nanocomposites, is an important subgroup within the material chemistry umbrella. One such example of nanocomposite systems is peapod-like structures that are composed of 0D nanoparticles (“peas”) and 2D nanosheets (“pods”). Nanopeapods may display unique properties that were not attainable within individual components. BaTiO3 nanoparticles can be produced using solvothermal methods (20 h) in the presence of Ba(NO3)2, titanium (IV) butoxide, and oleic acid as the surfactant. Synthesis parameters were modified to allow for both oleic acid and oleylamine to be present within solvothermal synthesis. The resulting nanopeapods had dimension between 0.1 – 1 μm with an average of 27 ± 14 particles within each scroll.
Nanomaterials that exhibit spin-crossover (SCO) type behavior have also been explored significantly due to its ability to be a molecular switch. Depending on the type of ligand used in its fabrication and the size of the SCO compound produced, the energy requirement for spin state transition can decrease. Here, a study is presented on the fabrication of 0D [Fe(Htrz)2(trz)](BF4)] nanocubes using adaptions of reverse micelle methods using Tergitol NP-9 as the surfactant. Resulting nanocubes obtained had dimensions of 50 nm. Clear evidence of decrease in energy requirements is seen in both thermal and magnetic hysteresis produced for the nanoparticles. Compared to bulk data, a decrease of 20 οC can be seen in transitions from low to high spin states.
The fabrication of transition metal oxynitrides via ammonolysis of transition metal oxides is a type of reaction that is studied for a variety of applications. Successful ammonolysis of niobium transition metal oxides is difficult due the reduction of the metal by the H2 produced. Ammonolysis of K4Nb6O17 at 800 οC produced a proposed two-phased oxynitride containing KNbO3 and a compound with the approximate composition of NbN0.33O2. The conversion resulted in a weight loss of 11% due to the loss of potassium oxides and exchange of oxygen atoms for nitrogen atoms within the structure. This was then proceeded by a weight gain of 6% during oxidation via thermal analysis. XRD analysis provided further structural details to confirm the two-phased system produced.
Blanco, Alexis A., "Nanomaterial Composites Based on Potassium Hexaniobate, Perovskites, and Iron Triazole Spin Crossover Complexes" (2020). University of New Orleans Theses and Dissertations. 2839.