Highly effectual photocatalytic degradation of tartrazine by using Ag nanoparticles decorated on Zn-Cu-Cr layered double hydroxide@ 2D graphitic carbon nitride (C 3 N 5 )

Pollution of water resources is one of the main concerns of many countries. This issue originates from the entry of diverse pollutants, including dye compounds, into water sources. In this work, ternary Zn-Cu-Cr layered double hydroxides (LDH) supported on graphitic carbon nitride (g-C 3 N 5 ) decorated by silver nanoparticles (C 3 N 5 -LDH-Ag) was first prepared. Application of various characterization techniques such as SEM, XRD, and FT-IR revealed that the synthesized nanocomposite was composed of Zn-Cu-Cr LDH nanoparticles, g-C 3 N 5 nanosheets, and Ag nanoparticles. The prepared nanomaterials were employed for the photodegradation of tartrazine in aqueous solutions. It was found that the C 3 N 5 -LDH-Ag catalyst outperformed their pure g-C 3 N 5 , Zn-Cu-Cr LDH, and C 3 N 5 -LDH composite in photocatalytic degradation of tartrazine under visible light irradiation. Tartrazine (20 mg/L) can be entirely removed by 0.25 g/L C 3 N 5 -LDH-Ag photocatalyst under 1 h visible light irradiation (200 W) at pH 6 with a rapid degradation rate constant ( k ) that is 4.4, 3.9, and 2.6 times higher than that of pure C 3 N 5 , Zn-Cu-Cr LDH, and C 3 N 5 -LDH component, respectively. The formation of hydroxyl radicals on the surface of C 3 N 5 -LDH-Ag as the main active species was approved by the capturing experiment. The finding results approved the stability and reusability of C 3 N 5 -LDH-Ag in four photocatalytic degradation cycles. In general, our findings revealed that the synthesized nanocomposite could be employed as an efficient photocatalyst in environmental remediation.