Artificial nano-sized ZnAgO/ZnO/ZnAlO composite material for photocatalytic applications

Low-temperature-assisted co-precipitation was used to generate artificial nano-sized ZnAgO/ZnO/ZnAlO composite material with Al and Ag impurity concentrations of 0 %–5 % and 0 %–2 %, respectively. The composite material characteristics were investigated using XRD, FE-SEM, HR-TEM, EDS, optical absorption, and FTIR. The photocatalytic activity was determined by decomposing RhB under mercury lamp. Material characteristics were also assessed using SCAPS-1D software. The shift of the diffraction peaks demonstrated that Al and Ag participated in ZnO crystal lattice. Diffraction peaks arise at 2θ of 32.2°, 39.1°, and 46.3° when Al and Ag impurities exceed 3 % and 1 % mol, respectively. At 32.2° and 46.3°, the Ag2O peak in the [002] and [220] planes are responsible. The peak at 39.1° related to Al interstitial in ZnO crystal lattice (32.2°) or Al2O3 impurity formation. The composite material size is less than 50 nm, and the dispersion is homogenous, according to FE-SEM images. Impurity centers in composite material show optical absorption at 2.7 eV, broadening the absorption to the visible region. The Raman spectrum indicates the existence of wurtzite ZnO, while the supplementary peaks suggest that Ag and Al doping alters the vibrational characteristics of the ZnO lattice. The PL spectrum show that Ag and Al doping creates a variety of defect states, enhancing the optical properties of the material, especially in the visible region, while maintaining the main UV emission of the ZnO structure. The artificial nano-sized Zn0.99Ag0.01O/ZnO/Zn0.99Al0.01O composite material decomposes RhB and Phenol entirely after 15 min of Hg lamp illumination. The reduction in TOC suggests that this catalyst promotes the oxidation and breakdown of organic contemine effectively. SCAPS-1D shows that the most optimal material parameters are ZnAlO layer donor density and thickness of 5 × 1017 cm−3 and 60 nm, respectively, and ZnAgO layer of 1 × 1016 cm−3 and 150 nm.