• Arshad, Muhammad
• Murtaza, Maida
• Waseem, Amir
• Alhodaib, Aiyeshah

Abstract

<jats:p>Pristine lanthanum nickelate (LaNiO<jats:sub>3</jats:sub>), silver phosphate (Ag<jats:sub>3</jats:sub>PO<jats:sub>4</jats:sub>) and perovskite lanthanum nickelate silver phosphate composites (LaNiO<jats:sub>3</jats:sub>/Ag<jats:sub>3</jats:sub>PO<jats:sub>4</jats:sub>) were prepared using the facile hydrothermal method. Three composites were synthesized by varying the percentage of LaNiO<jats:sub>3</jats:sub> in Ag<jats:sub>3</jats:sub>PO<jats:sub>4</jats:sub>. 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<jats:sub>3</jats:sub>/Ag<jats:sub>3</jats:sub>PO<jats:sub>4</jats:sub> 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<jats:sub>3</jats:sub>PO<jats:sub>4</jats:sub> were also enhanced by introducing LaNiO<jats:sub>3</jats:sub> in Ag<jats:sub>3</jats:sub>PO<jats:sub>4</jats:sub> heterojunction formation. Complete photodegradation of 50 mg/L of RhB and MO solutions using 25 mg of 5%LaNiO<jats:sub>3</jats:sub>/Ag<jats:sub>3</jats:sub>PO<jats:sub>4</jats:sub> photocatalyst was observed in just 20 min. Photodegradation of RhB and MO using 5%LaNiO<jats:sub>3</jats:sub>/Ag<jats:sub>3</jats:sub>PO<jats:sub>4</jats:sub> catalyst follows first-order kinetics with rate constants of 0.213 and 0.1804 min<jats:sup>−1</jats:sup>, respectively. Perovskite LaNiO<jats:sub>3</jats:sub>/Ag<jats:sub>3</jats:sub>PO<jats:sub>4</jats:sub> photocatalyst showed the highest stability up to five cycles. The photodegradation mechanism suggests that the holes (<jats:bold><jats:italic>h</jats:italic></jats:bold><jats:sup>+</jats:sup>) and superoxide anion radicals <jats:inline-formula><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="m1"><mml:mrow><mml:mfenced open="" close=")" separators="|"><mml:mrow><mml:msubsup><mml:mrow><mml:mfenced open="(" close="" separators="|"><mml:mrow><mml:mi mathvariant="bold-italic">O</mml:mi></mml:mrow></mml:mfenced></mml:mrow><mml:mn mathvariant="bold">2</mml:mn><mml:mrow><mml:mtext> </mml:mtext><mml:mo>•</mml:mo><mml:mo>−</mml:mo></mml:mrow></mml:msubsup></mml:mrow></mml:mfenced></mml:mrow></mml:math></jats:inline-formula> plays a main role in the dye degradation of RhB and MO.</jats:p>

Topics

• perovskite
• silver
• scanning electron microscopy
• composite
• powder X-ray diffraction
• Lanthanum
• Energy-dispersive X-ray spectroscopy