Iron titanate nanopowders with a particle size range of 48-70 nm could be obtained after calcinations of the dried gel at 900 C for 2 h. Fe 2 TiO 5 indicates a ferrimagnetic-paramagnetic behaviour, as evidenced by using vibrating sample magnetometer at room temperature. In the temperature range of 25-300 C the empirical equation of the heat capacity C p (J/mol K) ¼ À692.328 þ 1.39 T þ 3.757 Â 10 7 /T 2 for Fe 2 TiO 5 was determined from differential scanning calorimetry. Direct optical band gap of Fe 2 TiO 5 was calculated using the Tauc model by UV-Vis diffuse reflectance spectroscopy. Band gap energy of Fe 2 TiO 5 was determined as 1.95 eV.

Defects in metal nanoparticles can play a critical role in directing interfacial processes, such as catalytic reactions, at the surface of these materials. Interest in understanding the fundamental role of crystalline defects in controlling nanoparticle properties has inspired exploration of synthetic methods for tuning the twin defect structure of metal nanoparticles. However, controlling this structural parameter is a challenge due to the subtle reaction kinetics that dictate defect formation. For plasmonic silver (Ag) nanomaterials, the potential for light-induced growth provides a unique opportunity for driving structural reconfiguration between nanoparticle morphologies with different twin defect structures. We report a plasmon-mediated reconfiguration pathway in which {111}-faceted Ag nanoparticles are sequentially converted: first from planar twinned triangular Ag prisms to multiply twinned icosahedra (along with a smaller subpopulation of other twinned shapes), subsequently to multiply twinned Ag nanospheres, and finally back to planar twinned triangular Ag prisms. These consecutive reconfiguration processes occur as a result of the precise manipulation of reaction kinetics using a combination of illumination wavelength and pH. This method provides a valuable tool for reconfiguring, recycling, and regenerating Ag nanoparticles.

Fine-tuning of metal ion reduction kinetics is crucial to the successful synthesis of designer bimetallic nanomaterials with well-defined morphologies and tailored localization of the constituent elements for use in catalysis, sensing, and other applications. However, achieving desired reduction kinetics can be challenging within the restrictions of available reducing agents, seed particle stability, metal ion solubility, and competing chemical processes such as galvanic exchange. Herein, we report the plasmon-assisted reduction of Pt ions onto Ag cores by using visible light illumination to accelerate the oxidation kinetics of a weak reducing agent, trisodium citrate. Using this approach, we are able to synthesize both core–shell and core–satellite structures composed of a plasmonic Ag core and a poorly plasmonic Pt shell or satellites. The controlled formation of these hybrid structures relies on the plasmon-mediated enhancement of the Pt ion reduction rate into a range where, under standard thermal conditions, reduction with citrate is too slow and reduction using even low concentrations of a slightly stronger reducing agent is too fast. This work expands the scope of citrate-assisted plasmon-mediated synthesis to metals other than Ag, opening possibilities for using plasmon-enhanced reduction by citrate as a more generalizable synthetic tool.

Pure phase NiTiO 3 was obtained via a modified sol-gel method. Addition of CeO 2 in a modified oxidizing atmosphere in stearic acid at 750°C led to the growth of several nanoscaled Ce-rich phases. The formation of NiTiO 3 and CeO 2 /NiTiO 3 was strongly confirmed based on metal-oxygen and metal-metal absorption bands. The nanometric formation of crystals and narrow distribution of nanoparticles were confirmed by XRD and FE-SEM. The magnetic properties indicated weak ferromagnetic behavior of NiTiO 3 and paramagnetic behavior of CeO 2 /NiTiO 3 nanocomposites. The paramagnetic properties were improved gradually into superparamagnetic upon increasing CeO 2 domain to 30 mol%. It was observed that the current density can achieve 1 × 10 −9 A/cm 2 for the sample containing 30 mol% CeO 2 at an electrical field equal to 40 V/cm.

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