Self-supported Ag nanoparticles on AgTi2(PO4)3 for hazardous dyes reduction in industrial wastewater

Abstract

Silver based-nanoparticles (Ag NPs) have been recently shown to be promising catalysts for the degradation of toxic organic dyes in wastewater despite the challenges of recycling. In this paper, self-supported Ag NPs were obtained at the surface of AgTi2(PO4)3 NASICON-type phosphates through in situ chemical reduction by sodium borohydride (NaBH4). The adopted approach enables the self-growth of zero-valent Ag NPs on the NASICON matrix, and concomitantly leads to the formation of Ag1−xNaxTi2(PO4)3. The crystalline structure, morphology and phase composition of the Ag nanocomposite has been characterized by several techniques. The catalytic performance of the as-fabricated Ag NPs/Ag1−xNaxTi2(PO4)3 has then been verified in the reduction of methylene blue (MB) and methyl orange (MO) dyes, chosen as target pollutants. Our findings reveal a good catalytic activity with an efficiency and time of reaction of respectively ∼ 96.30% and 320 s in the case of the MB reduction and ∼ 94.60% and 270 s in the case of the MO reduction. Additionally, the initial AgTi2(PO4)3 phase can be regenerated via simple calcination route and recycled up to five times with no appreciable loss of catalytic activity.