Band gap engineering of Ca(OH) 2 system by Ag nanoparticles incorporation: experimental and first-principle study

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.