Metal nanoparticles have demonstrated outstanding properties in photovoltaic devices through introducing localized surface plasmon effects. The performance of Perovskite solar cell (PSC) by incorporating Ag@P4VP NPs was investigated systematically. The plasmonic enhancement effects are explored based on the combination of UV-visible absorption spectroscopy and Scanning Electron Microscope (SEM). The performance, especially the short circuit current density (Jsc), and open circuit voltage (Voc) of the PSC containing Ag@P4VP NPs was significantly affected. The power conversion efficiency (PCE), Jsc and Vocof the reference device shows a value of 3.80 %, 11.04 mAcm−2 and 0.85 V. Upon introducing AgNPs@P4VP, a PCE of 5.69 %, Jsc of 12.61 mAcm−2 and Voc of 0.88 V were recorded, which improved the PCE ∼ 39.4 % over that of the standard device. The improvement is attributed to an increase in photocurrent density due to enhanced light harvesting by silver nanoparticles.

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Twelve samples of water from hand-dug wells in some parts of Kaduna South and its Environs were selected using a stratified random sampling. Twenty (20mils) of concentrated nitric acid were added to each two liters of the sampled water for preservation. The samples were then evaporated and counted for Gross Alpha activity using MPC-2000-DP model gas free proportional counter at Centre for Energy Research and Training (CERT), Ahmadu Bello University, Zaria.  Results show that, the range of alpha activity in water in the area was 0.001 to 0.413 Bq/L, with geometric mean of 0.124±0.040 Bq/L. The overall results show that, the alpha activity have their values below WHO recommended practical screening level of 0.5 Bq/L radioactivity for drinking water.

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Abstract:We present an investigation on introducing core-shell Ag@SiO 2 nanoparticles (NPs) into dye-sensitized solar cells. Ag@SiO 2 present the chemical stability to iodide/triiodide electrolyte, and help to localize most of dye molecules around plasmonic silver nanoparticles (AgNPs), hence increasing the optical absorption consequently the overall conversion efficiency of the device. Deployment of the silver-modified assembly as a photo anode in dye-sensitized solar cells leads to solar-toelectrical energy conversion with an overall efficiency of 0.0088% for Ag-TiO 2 photo anode and 0.0176% for Ag@SiO 2 -TiO 2 photo anode. This represents a 100.7% improvement over the performance of otherwise identical solar cell lacking corrosionprotected silver nanoparticles. The improvement is manifested chiefly as an increase in photocurrent density due to enhanced light harvesting by the AgNPs. The results revealed that, the performance of DSSCs could be well improved through enhancing the light absorption by local surface plasmon (LSP) effect from Ag@SiO 2 NPs by electronically and chemically protecting the metal from recombination and corrosion. The mechanism of getting the best utilization efficiency of LSP enhanced optical field is also investigated.

Titanium dioxide (TiO2) has gained a lot of research interests due to its applicability in electronic materials, energy, environment, health & medicine, catalysis etc as a result of its high permittivity, refractive index, efficiency, low-cost chemical inertness, eco-friendliness, photocatalytic activity, photostability and ability of decomposing a wide variety of organic compounds. In this study, the effect of silver nanoparticles (AgNPs) deposited through Successive Ionic Layer Adsorption and Reaction (SILAR) on the optical, structural and morphological properties of TiO2 was explored systematically. The investigation was achieved via a combined effect of UV-vis spectroscopy, Scanning Electron Microscope (SEM) and X-ray Diffractometer (XRD) characterizing tools. As illustrated from the SEM micrographs, introduction of AgNPs result to enhanced nucleation and films growth with presence of shining surface which can be seen to contribute to good photon management through enhanced light scattering. The XRD results showed that, the presence of AgNPs on TiO2 results to peaks corresponding to that of the TiO2 crystallographic planes with no silver peaks detected due to its low concentration in the nanocomposite which shows that it was just homogeneously distributed on the surface of the TiO2 nanoparticles. The UV-Vis results show a red shift to higher wavelength, showing an increase in visible light absorption which can be ascribed to the strong field effect of the Localized Surface Plasmon Resonance (LSPR). There was a decrease in band gap edge with introduction of AgNPs which indicated an increase in the optical conductivity of the AgNPs modified film.

This work present the Uranium (238U) content in soil samples collected in Ajaokuta from some villages was been determined. The measurement of the soil Uranium activity concentration were made using a multi–channel pulse height analyzer (Camberra series 10 plus) coupled to a 76.2mm x 76.2mm NaI (TI) scintillation detector. 2.93)The mean Uranium content in the analyzed samples was found to be (44.26 Bq/kg which is higher than the world mean value of 35Bq/kg. The results were in good agreement with others for soils from region which is considered as normal or slightly high in radioactivity level.