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Exploiting the plasmonic behavior of Ag nanoparticles grown on α-Ag 2 WO 4 is a widely employed strategy to produce efficient photocatalysts, ozone sensors, and bactericides. However, a description of the atomic and electronic structure of the semiconductor sites irradiated by electrons is still not available. Such a description is of great importance to understand the mechanisms underlying these physical processes and to improve the design of silver nanoparticles to enhance their activities. Motivated by this, we studied the growth of silver nanoparticles to investigate this novel class of phenomena using both transmission electron microscopy and field emission scanning electron microscopy. A theoretical framework based on density functional theory calculations (DFT), together with experimental analysis and measurements, were developed to examine the changes in the local geometrical and electronic structure of the materials. The physical principles for the formation of Ag nanoparticles on α-Ag 2 WO 4 by electron beam irradiation are described. Quantum mechanical calculations based on DFT show that the (001) of α-Ag 2 WO 4 displays Ag atoms with different coordination numbers. Some of them are capable to diffuse out of the surface with a very low energy barrier (less than 0.1 eV), thus, initiating the growth of metallic Ag nanostructures and leaving Ag vacancies into the bulk material. These processes increase the structural disorder of α-Ag 2 WO 4 as well as its electrical resistance as observed in the experimental measurements.S Online supplementary data available from stacks.iop.org/NANO/0/000000/mmedia

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O 9 thin films on Pt/Ti/SiO 2 /Si were successfully synthesized by the modified polymeric precursor method. The films were deposited by spin coating and crystallized by rapid thermal annealing in a halogen lamp furnace, followed by postannealing at temperatures ranging from 700°C to 800°C in an oxygen atmosphere. Microstructural and phase evaluations were followed by x-ray diffraction and atomic force microscopy. The films displayed spherical grain structures with a superficial roughness of approximately 3-6 nm. The dielectric constant values were 121 and 248 for films treated at 700°C and 800°C, respectively. The P -E curve showed a voltage shift toward the positive side, which was attributed to crystallization under the halogen illumination. The remanent polarization (2 P r ) and coercive field (E c ) were 7.1 C/cm 2 and 113 kV/cm, and 18.8 C/cm 2 and 93 kV/cm for the films treated at 700°C and 800°C, respectively.

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