Dielectric and antibacterial studies of microwave assisted calcium hydroxide nanoparticles

Calcium hydroxide nanoparticles (Ca(OH)(2)NPs) were formulated through microwave assisted route and characterized by XRD, FTIR and FESEM. It exhibits hexagonal crystal structure with an average crystallite size of 30 nm. The TEM images show the agglomerated nanoparticles. From the UV-Vis spectra, the bandgap is estimated as 5.5 eV. A broad emission band with maximum intensity at around 430 nm is observed in photoluminescence (PL) spectrum of Ca(OH)(2) NPs at room temperature. The dielectric constant and loss were studied as a function of frequency at room temperature (AE(r) = 25.0 and AE('') = 3.94 at 10 kHz).The relative powder second harmonic generation efficiency (SHG) of Ca(OH)(2) NPs is comparable with the standard KDP. Antibacterial activity of Ca(OH)(2) NPs at concentrations 15 and 30 A mu g/mL were screened against gram negative (Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa, Shigella flexneri, Proteus vulgaris, Klebsiella pneumoniae and Proteus mirabilis) and gram positive (Bacillus subtilis, Micrococcus luteus, and Streptococcus aureus) bacteria by measuring the inhibition zone.