Preparation, characterization, and optical properties of nanosized Al(III) 3-azo-phenolate salicylic acid thin film for potential application in nonlinear optical crystal

Abstract

Abstract The present research is concentrated on improving the characteristic properties of salicylic acid (SA) within the nonlinear optical crystal. So, the layer-by-layer (LBL) technique was utilized to design and make thin films of nanosized aluminum (III) complex of 3-azo-phenolate salicylic acid (NS Al(III)-3AP-SA) having a high specified surface area with various thicknesses. The synthesized material was deposited on glass and quartz substrates to investigate the structural and optical properties. Characterization of fabricated films was performed using TGA, X-ray, SEM, and FTIR. The prepared NS Al(III)-3AP-SA exhibited a spherical shape with a size between 41–61 nm. The optical transmission spectra were studied in the spectral range of 300 to 1100 nm at room temperature. The refractive index, absorption coefficient, and optical energy gap were determined. It was found that the optical energy gap = 3.78 eV without noticeable variation because of thickness increases. Together with their dependencies on the film thicknesses, the nonlinear and linear optical parameters have been calculated. The results suggest that the assembled NS Al(III)-(3AP-SA) can be categorized as a promising material for the fabrication of nonlinear optical crystal applications.