03132nas a2200181   4500008004100000022001400041245011800055210006900173260011000242300001600352490000600368520237100374100001902745700001702764700001802781700001902799856013202818       2016                        eng d  a2046-206900aBroad spectrum photon responsive, paramagnetic beta-NaGdF4: Yb3+, Er3+ - mesoporous anatase titania nanocomposite0 aBroad spectrum photon responsive paramagnetic betaNaGdF4 Yb3 Er3  aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcMAY  a53504-535180 v63 a<p>Herein, we report a novel single multifunctional platform based on broad-spectrum photoactive beta-NaGdF4:18% Yb3+, 2% Er3+ and mesoporous anatase TiO2 for enhanced energy and simultaneous biomedical applications. Currently, the photoactive materials for solar energy harvesting applications have limitations in their efficiency due to their narrow photon absorption spectrum. The upconversion phosphor beta-NaGdF4: 18% Yb3+, 2% Er3+ nanorods collect and harvest the NIR photons (similar to 980 nm) of sunlight and transform them into visible light via anti-Stokes emission (lambda(em) similar to 521 and similar to 540 nm), and the photoactive mesoporous anatase TiO2 (mTiO(2)) utilizes UV and weak visible photons, thus the composite forms a broad spectrum photon-capture system and improved power conversion efficiency for enhanced applications in photocatalysis, and dye sensitized solar cells (DSSCs). The photocatalytic activity of the nanocomposite showed an improvement in comparison to the mTiO(2) for the degradation of various dyes. In addition, the photocurrent density and solar cell efficiency of the nanocomposites showed an improvement by similar to 24% and similar to 17% respectively, over mTiO(2). The beta-NaGdF4: Yb3+, Er3+/mTiO(2) nanocomposite exhibits a strong paramagnetic signal (chi similar to 6.45 x 10(-5) emu g(-1) Oe(-1)). The nuclear magnetic resonance (NMR) measurements showed large longitudinal T1 relaxivity (r(1) = 7.09 s(-1) mM(-1)) and magnetic resonance imaging showed enhanced T-1-weighted MRI images with increased concentrations of beta-NaGdF4: Yb3+, Er3+/mTiO(2) nanocomposite making them suitable for simultaneous magnetoresonance imaging. In addition, this composite system can also be used as a NIR triggered drug delivery system and in biomedical applications. Moreover, mesoporous TiO2 is expected to increase the photocatalytic active sites, dye, and absorption, and drug loading capacity. The as-designed multifunctional beta-NaGdF4:Yb3+, Er3+/mTiO(2) nanocomposite possessed simultaneous multiple discrete functionalities with excellent luminescence properties, intrinsic paramagnetism, biocompatibility, improved photocatalytic activity, and solar cell efficiency. This work provides a promising system to utilize NIR light, which will contribute to efficient photon harvesting and biological applications.</p>1 aPadhye, Preeti1 aSadhu, Subha1 aMalik, Monika1 aPoddar, Pankaj  uhttps://library.ncl.res.in/content/broad-spectrum-photon-responsive-paramagnetic-beta-nagdf4-yb3-er3-mesoporous-anatase-titania