Perovskite LaNiO3/Ag3PO4 heterojunction photocatalyst for the degradation of dyes

• Published in: Frontiers in chemistry Vol. 10; p. 969698
• Main Authors: Ameen, Shahzad, Murtaza, Maida, Arshad, Muhammad, Alhodaib, Aiyeshah, Waseem, Amir
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 08.12.2022
• Subjects: Chemistry; dyes; lanthanum nickelate; photocatalysis; silver phosphate; water pollution
• ISSN: 2296-2646; 2296-2646
• DOI: 10.3389/fchem.2022.969698

Pristine lanthanum nickelate (LaNiO 3 ), silver phosphate (Ag 3 PO 4 ) and perovskite lanthanum nickelate silver phosphate composites (LaNiO 3 /Ag 3 PO 4 ) were prepared using the facile hydrothermal method. Three composites were synthesized by varying the percentage of LaNiO 3 in Ag 3 PO 4 . The physical properties of as-prepared samples were studied by powder X-ray diffraction (pXRD), Fourier-transform infrared (FT-IR), Scanning electron microscopy (SEM) and Energy-dispersive X-ray (EDX). Among all synthesized photocatalysts, 5%LaNiO 3 /Ag 3 PO 4 composite has been proved to be an excellent visible light photocatalyst for the degradation of dyes i.e., rhodamine B (RhB) and methyl orange (MO). The photocatalytic activity and stability of Ag 3 PO 4 were also enhanced by introducing LaNiO 3 in Ag 3 PO 4 heterojunction formation. Complete photodegradation of 50 mg/L of RhB and MO solutions using 25 mg of 5%LaNiO 3 /Ag 3 PO 4 photocatalyst was observed in just 20 min. Photodegradation of RhB and MO using 5%LaNiO 3 /Ag 3 PO 4 catalyst follows first-order kinetics with rate constants of 0.213 and 0.1804 min −1 , respectively. Perovskite LaNiO 3 /Ag 3 PO 4 photocatalyst showed the highest stability up to five cycles. The photodegradation mechanism suggests that the holes ( h + ) and superoxide anion radicals O 2   • − plays a main role in the dye degradation of RhB and MO.