Band gap engineering of Ca(OH)2 system by Ag nanoparticles incorporation: experimental and first-principle study
摘要
Ag nanoparticles (NPs)-incorporated Ca(OH)2 nanostructures were synthesized by the chemical precipitation method. X-ray diffraction, Field Emission Scanning Electron Microscope (FESEM), Energy-Dispersive X-ray spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy, and UV–Vis spectroscopy techniques were used to characterize the synthesized powder samples. The Ag NPs incorporation in Ca(OH)2 modifies the size and morphology of the Ca(OH)2 nanostructures and shifts the absorption edge of Ca(OH)2 toward visible light. These findings point out the possibility to customize the band gap and optical absorbance of Ag-incorporated Ca(OH)2 by adjusting the Ag concentration. Density-functional theory-based first-principle calculations are used to determine the optical properties of the pure Ca(OH)2 and Ag NPs-incorporated Ca(OH)2, their shapes, and their electronic characteristics to complement and rationalize the experimental data. The first-principle calculation results are consistent with recent experimental results of reduction in optical band gap energy with an increase in Ag NPs concentration. The theoretical insights provide a plausible justification for experimental results.