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Silver-containing materials have been the source of attraction due to their excellent optical and photocatalytic properties. Silver vanadium phosphate, Ag 2 VO 2 PO 4 , (hereafter abbreviated as AVP) in nanorods form was synthesized by hydrothermal method at 220 °C for 24 h and characterized by PXRD, FT-IR, 31 P MAS NMR, SEM-EDS, TEM-SAED, N 2 adsorption-desorption, UV-Vis DRS and XPS techniques. It was crystallized in the monoclinic crystal lattice with space group C2/m and the crystal structure consists of layers of edge-sharing VO 6 octahedra and PO 4 tetrahedra. The Ag 2 VO 2 PO 4 nanorods have shown the photocatalytic property against the degradation of Rhodamine B (RhB) dye. The degradation of RhB by AVP after 180 min of visible light irradiation was 45 %. The photocatalytic activity of this material was explained by its visible light absorption, which makes it a promising photocatalyst for use in solar photocatalysis and with a good photocatalytic rate. A mechanism for photodegradation of RhB dye was proposed based on scavenger experiments. It was noticed that * OH radicals are actively participating in the degradation of RhB followed by holes while the role of O 2 *À radicals is negligible. Antibacterial activity of this material was studied over gram-positive Staphylococcus aureus and gram-negative Pseudomonas aeruginosa bacteria.

Visible light‐driven photocatalysis has gained much attention due to its light‐harnessing characteristics and is extensively used in wastewater remediation. This paper presents a novel oxygen‐deficient manganese antimonate, MnSb2O6‐x, with a trirutile structure as an effective visible‐light‐driven photocatalyst for dye degradation. The synthesized samples were subjected to XRD, UV‐Vis DRS, SEM‐EDS, Raman, XPS, and PL analyses to study their physic chemical properties. The influence of sequential or single heating during the preparation method on the generation of oxygen vacancies is evaluated using UV‐Vis DRS, XPS, ESR, and Raman techniques. The oxygen‐deficient MnSb2O6 could achieve up to 85 % of MO degradation in 180 min under visible light irradiation, and its reusability up to six cycles was also investigated. In addition, the mechanism of dye degradation was supported with a scavenger test, and the degradation activities are correlated to the electron‐hole pair separation as convinced from the PL spectra. The simple and unique method of oxygen vacancy generation can inspire the development of antimonates with oxygen deficiencies, which have significant scope of application in environmental and energy conservation.

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Defect pyrochlore-type oxide, KGe 0.5 Te 1.5 O 6 (KGTO) and its Ag + , Cu 2 + and Sn 2 + doped compositions were prepared by solid state and ion-exchange methods respectively. The XRD results suggest that both parent KGTO and Ag + , Cu 2 + and Sn 2 + doped KGTO have crystallized in cubic lattice. The morphology of all compositions was obtained from SEM-EDS and TEM-SAED measurements. The textural properties were obtained from N 2 adsorption-desorption measurements. The FT-IR and Raman spectra of all compositions are comparable. Surface elemental composition and electron-hole recombination rate were deduced from XPS and PL measurements respectively. The photocatalytic performance of these materials was tested in the degradation of methylene blue (MB) and methyl orange (MO) dyes. The doping of Ag + , Cu 2 + and Sn 2 + into the KGTO lattice improved optical characteristics and photocatalytic activity significantly. Among the compositions investigated, Sn-KGTO shown highest photocatalytic performance with 82 % for MB and 67 % for MO in 180 min. Trapping experiments were conducted to identify the active species participated in the MB degradation over Sn-KGTO. The generation and participation of * OH and O 2 À * radicals were studied by terephthalic acid and potassium bromate experiments respectively. The reusability and chemical stability of Sn-KGTO against MB degradation were also examined. A possible reaction mechanism was proposed to understand the MB degradation in the presence of Sn-KGTO.