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Photocatalytic activity of TiO 2 (anatase) is appreciably enhanced by substitutional doping of Mo in anatase lattice, in conjunction with the incorporation of nanostructured MoO 3 within the parent anatase lattice. The photocatalyst material was characterized in detail using X-ray diffraction, Raman spectroscopy, diffuse reflectance (DR-UV− Vis spectroscopy), X-ray photoelectron spectroscopy, and electron microscopy. Photocatalysis experiments were conducted using a model rhodamine-B (Rh−B) dye reaction using both UV and visible irradiation sources. The observed trends in the case of visible irradiative source can be summarized as follows: Mo-1 < Mo-2 < Mo-5 ≫ Mo-10. Attempts were made to isolate the structural factors that control photochemical behavior of these Mo−TiO 2 photocatalysts and to correlate photocatalytic activity with different structural aspects like oxidation state, band gap, surface species, etc. Mechanistic insights were acquired from ex situ 1 H NMR studies showing different intermediates and different probable routes for the Rh−B dye degradation with UV and visible radiations. The stable intermediates were formed by a direct oxidative fragmentation route, without any evidence of the initial deethylation route. The intermediates found were benzoic acid, different amines, diols, and certain acids (mostly formic and acetic acid). The adsorption of the Rh−B dye on the catalytic surface via the N-charge centers of the Rh−B was also observed.

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We report the development of a new class of water-dispersible polyphosphate grafted Fe3O4 nanomagnets (PPNM) by a facile soft-chemical approach. The grafting of polyphosphate with Fe3O4 nanoparticles was evident from Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), dynamic light scattering (DLS) and zeta-potential measurements. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses reveal the formation of highly crystalline Fe3O4 nanoparticles with average size of about 10 nm. These nanoparticles show good colloidal stability, strong magnetic field responsivity and protein resistance characteristics. The induction heating studies confirmed localized heating of these superparamagnetic PPNM with good intrinsic loss power under AC magnetic field (AMF). The drug loading and release behavior of PPNM was explored using doxorubicin hydrochloride (DOX) as a model drug. The decrease of fluorescence intensity and surface charge of drug loaded PPNM strongly suggest the conjugation of DOX with PPNM. The cell viability and hemolysis assays suggest that PPMN do not have adverse toxic effects for further in-vivo use. Specifically, high loading affinity for DOX with their sustained release, substantial cellular internalization and self-heating capacity makes these novel magnetic nanoparticles suitable for drug delivery and hyperthermia therapy applications.