Photocatalytic performance of Ni-Al LDH @Ag2XO4 (X = Cr, Mo, and W) nanocomposites under visible light

Abstract

The contamination of water sources from dye discharge poses a significant environmental challenge. This study addresses this issue by synthesizing binary composites of Ni-Al LDH@Ag₂XO₄ (with X=Cr, Mo, and W). The main goal is to increase the separation of charge carriers to boost the efficiency of photocatalysis. The prepared samples were analyzed using FT-IR, FE-SEM, EDS, FE-TEM, XRD, UV–Vis DRS, and XPS techniques. Observations revealed a notable increase in MB degradation through photocatalysis under a 150 W mercury lamp in presence of Ni-Al LDH@Ag₂CrO₄ compared to individual samples, Ni-Al LDH and Ag₂CrO₄. At pH= 11, 0.5 g of Ni-Al LDH@Ag₂CrO₄ shows the highest activity (100 %) for the photodegradation of MB. The absorption edge of Ni-Al LDH@Ag₂CrO₄ (1.69 eV) has increased compared to that of Ni-Al LDH (2.53 eV), which increases the light absorption capacity. Moreover, the synergistic effect of Ni-Al LDH and Ag₂CrO₄ increases photocatalytic activity by reducing electron-hole recombination. The proposed Z-Scheme mechanism confirms effective charge separation and increased photocatalytic efficiency.