Exfoliated Hydrotalcite-Transition Metal Complex Composite for Eco-Friendly and Efficient Catalytic Degradation of 4-Nitrophenol

Nitrophenols are notorious aquatic organic contaminants found as degradation products of various parent compounds, including pesticides and industrial chemicals that persist in the environment and must be removed. Catalytic degradation is one of the feasible routes to clean the contaminated water systems, however, environmental contamination with catalysts is also widespread. Herein, we report an environmentally friendly catalyst based on composited Fe-Schiff’s base with exfoliated layered double hydroxides (LDH) of aluminum and nickel (hydrotalcite). The composite showed agglomerated pleated LDH structures sheathed with Fe(III)SB. Nitrogen adsorption isotherm data exhibited improved surface area and narrow pores patterns for composite as compared to LDH indicating Fe(III) SB-induced change in the morphology of LDH. Also, significant improvement in catalytic efficiency was observed for Fe(III)SB-LDH over pristine LDH. 4-nitrophenol (10 mg/L) degradation of 99% in five minutes was achieved at pH 6 using a catalyst-to-volume ratio of 1:20 and 20 mM H2O2 as oxidant. It is concluded that phenomenal improvement in catalyst efficiency can be attributed to Fe-Schiff’s base modification.