Defect-Mediated Formation of Ag Cluster-Doped TiO₂ Nanoparticles for Efficient Photodegradation of Pentachlorophenol

Abstract

A novel strategy was designed to prepare Ag cluster-doped TiO(2) nanoparticles (Ag/TiO(2) NPs) without addition of any chemical reducing agent and/or organic additive. A defect-rich TiO(x) species was generated by laser ablation in liquid (LAL) of a Ti target. The silver ions could be reduced and deposited on the surface of TiO(2) NPs through the removal of oxygen vacancies and defects; the TiO(x) species evolved into anatase NPs in a hydrothermal treatment process. The derived Ag/TiO(2) NPs are approximately 25 nm in size, with narrow size distribution. The Ag clusters are highly dispersed inside TiO(2) and less than 3 nm in size. The doped amount can be tuned by changing the concentration of Ag(+) ions. The as-synthesized Ag/TiO(2) NPs display improved photocatalytic efficiency toward pentachlorophenol (PCP) degradation.

A Convenient Method to Prepare Ag Deposited N-TiO2Composite Nanoparticles via NH3Plasma Treatment

“…Therefore, the Ag clusters existed in metallic form. 29 Therefore, it is indicated that AgO were reduced to metallic Ag successfully by NH 3 or H 2 plsama treatment. Figure 5 shows a comparison of the photocurrent density vs applied potential curves for the P25 and P25 and prepared TiO 2 composites under visible light irradiation.…”

P-doped TiO2 with superior visible-light activity prepared by rapid microwave hydrothermal method

“…However, only the ultraviolet part of the solar spectra could be absorbed by pure TiO 2 to exhibit its photocatalytic activity. Several strategies have been developed to enhance its visible-light photoactivity including doping of transitional metal ions and nonmetal elements [4][5][6][7], among which nonmetal phosphorous (P)-doping has aroused much attention recently [4,8]. For example, Jin et al used hypophosphorous acid as P precursor to synthesize P-TiO 2 by hydrothermal method [3].…”

Silver nanoparticles decorated anatase TiO 2 nanotubes for removal of pentachlorophenol from water

“…Therefore, the Ag nanoparticles act to trap the photo-generated electrons, which can inhibit the fast recombination of photo-generated electrons and holes, and thus enhance the photocatalytic performance under simulated solar light irradiation [37]. Ingram and Linic [43] verified that electrons on the Ag/TiO 2 composite surface can be scavenged by the existing O 2 molecules to generate reactive oxygen radicals (O 2 À ), leading to strong photocatalytic activities, at the same time, the valence band holes can react with the absorbed OH À and/or H 2 O molecules to produce hydroxyl radicals ( Á OH) which possess high oxidizability [44]. The generated hydroxyl radicals may attack organic contaminants like PCP.…”