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A multi-element perovskite nanoscale film composed of Li(+) cation incorporated into Ca(2+)-doped PbTiO(3) (LCPT) was derived via colloidal chemistry, sol-gel (SG) method followed by heat-treatment. The morphology, chemical composition and structure of the LCPT nanofilms were investigated by advanced instrumentation (microscopy and spectroscopy) techniques. The characterization indicates formation of a tetragonal crystalline ceramic after sintering. The humidity sensing performances of LCPT nanofilms with various formulations were evaluated as a function of lattice distortion. The LCPT sensor doped with Li (0.5-0.1mol%) possessed the distortion of 1.041-1.046 and displayed rapid sensitivity (current changes from 1.5x10(-3) to 5.2A), high linearity (R(2)=0.997) in the whole relative humidity range (phi: 8-93% RH) under low frequency of 100Hz, and excellent long-term stability.

Silver nanoparticles (Ag-NPs) were synthesized using a facile green chemistry synthetic route. The reaction occurred at ambient temperature with four reducing agents introduced to obtain nanoscale Ag-NPs. The variables of the green synthetic route, such as acidity, concentration of starting materials, and molar ratio of reactants were optimized. Dispersing agents were employed to prevent Ag-NPs from aggregating. Advanced instrumentation techniques, such as X-ray powder diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible spectroscopy (UV-vis), and phase analysis light scattering technique (ZetaPALS) were applied to characterize the morphology, particle size distribution, elemental composition, and electrokinetic behavior of the Ag-NPs. UV-vis spectra detected the characteristic plasmon at approximately 395-410 nm; and XRD results were indicative of face-centered cubic phase structure of Ag. These particles were found to be monodispersed and highly crystalline, displaying near-spherical appearance, with average particle size of 10.2 nm using citrate or 13.7 nm using ascorbic acid as reductants from particle size analysis by ZetaPALS, respectively. The rapid electrokinetic behavior of the Ag was evaluated using zetapotential (from -40 to -42 mV), which was highly dependant on nanoparticle acidity and particle size. The current research opens a new avenue for the green fabrication of nanomaterials (including variables optimization and aggregation prevention), and functionalization in the field of nanocatalysis, disinfection, and electronics.