Investigating the Electron Transport and Light Scattering Enhancement in Radial Core-Shell Metal-Metal Oxide Novel 3D Nanoarchitectures for Dye Sensitized Solar Cells

Dye-sensitized solar cells (DSSCs) have attained considerable attention during the last decade because of the potential of becoming a low cost alternative to silicon based solar cells. Electron transport is one of the prominent processes in the cell and it is further a complex process because the transport medium is a mesoporous film. The gaps in the pores are completely filled by an electrolyte with high ionic strength, resulting in electron-ion interactions. Therefore, the electron transport in these so called state-of-the-art systems has a practical limit because of the low electron diffusion coefficient (Dn) in this mesoporous film photoanode. This work focuses on the influence of the advanced core-shell nanoarchitecture geometry on electron transport and also on the influence of electron-ion interactions. In order to achieve the proposed goals, DSSCs based on ordered, highly aligned, 3D radial core-shell Au-TiO2 hybrid nanowire arrays were fabricated, using three different approaches. J-V, IPCE, and EIS characteristics were studied. The efficiency, light scattering and charge transport properties of the core-shell nanowire based devices were compared to TiO2 nanotube as well as TiO2 mesoporous film based DSSCs. The Au nanowires inside the crystalline TiO2 anatase nanoshell provided a direct conduction path from the TiO2 shell to the TCO substrate and improved transport of electrons between the TiO2 and the TCO. The optical effects were studied by IPCE measurement which demonstrated that Au-TiO2 nanowires showed an improved light harvesting efficiency, including at longer wavelengths where the sensitizer has weak absorption. The metal nanostructures could enhance the absorption in DSSCs by either scattering light enabling a longer optical path-length, localized surface plasmon resonance (LSPR) or by near-field coupling between the surface plasmon polariton (SPP) and the dye excited state. Rapid, radial electron collection is of practical significance because it should allow alternate redox shuttles that show relatively fast electron-interception dynamics to be utilized without significant sacrifice of photocurrent. A combination of improved electron transport and enhanced light harvesting capability make Au-TiO2 core-shell nanowire arrays a promising photoanode nanoarchitecture for improving photovoltaic efficiency while minimizing costs by allowing thinner devices that use less material in their construction

Investigating the Electron Transport and Light Scattering Enhancement in Radial Core-Shell Metal-Metal Oxide Novel 3D Nanoarchitectures for Dye Sensitized Solar Cells

Dye-sensitized solar cells (DSSCs) have attained considerable attention during the last decade because of the potential of becoming a low cost alternative to silicon based solar cells. Electron transport is one of the prominent processes in the cell and it is further a complex process because the transport medium is a mesoporous film. The gaps in the pores are completely filled by an electrolyte with high ionic strength, resulting in electron-ion interactions. Therefore, the electron transport in these so called state-of-the-art systems has a practical limit because of the low electron diffusion coefficient (Dn) in this mesoporous film photoanode. This work focuses on the influence of the advanced core-shell nanoarchitecture geometry on electron transport and also on the influence of electron-ion interactions. In order to achieve the proposed goals, DSSCs based on ordered, highly aligned, 3D radial core-shell Au-TiO2 hybrid nanowire arrays were fabricated, using three different approaches. J-V, IPCE, and EIS characteristics were studied. The efficiency, light scattering and charge transport properties of the core-shell nanowire based devices were compared to TiO2 nanotube as well as TiO2 mesoporous film based DSSCs. The Au nanowires inside the crystalline TiO2 anatase nanoshell provided a direct conduction path from the TiO2 shell to the TCO substrate and improved transport of electrons between the TiO2 and the TCO. The optical effects were studied by IPCE measurement which demonstrated that Au-TiO2 nanowires showed an improved light harvesting efficiency, including at longer wavelengths where the sensitizer has weak absorption. The metal nanostructures could enhance the absorption in DSSCs by either scattering light enabling a longer optical path-length, localized surface plasmon resonance (LSPR) or by near-field coupling between the surface plasmon polariton (SPP) and the dye excited state. Rapid, radial electron collection is of practical significance because it should allow alternate redox shuttles that show relatively fast electron-interception dynamics to be utilized without significant sacrifice of photocurrent. A combination of improved electron transport and enhanced light harvesting capability make Au-TiO2 core-shell nanowire arrays a promising photoanode nanoarchitecture for improving photovoltaic efficiency while minimizing costs by allowing thinner devices that use less material in their construction

Evaluation of antioxidant activity of flower and seed oil of Azadirachta indica A. juss

The present study on evaluation of antioxidant activity of the flowers and seed oil of Neem plant Azardirachta indica A. Juss revealed that the ethanolic extract of flowers and seed oil at 200 ?g/ml producing the highest free radical scavenging activity i.e. 64.17±0.02% and 66.34±0.06% respectively. The Neem oil has the highest amount of total phenol content (132 ?g/ml) which is responsible for highest percentage of inhibition of DPPH radical. In conclusion Neem flower and seed oil have potential for use in human health which is used as food by common people and in diabetes and Neem seed oil is widely used for variety of diseases and also antioxidant potential for use in different pharmaceutical industries

Biopesticidal effect of leaf extract of neem (Azadirachta indica A. Juss) on growth parameters and diseases of tomato

This paper investigates the potential use of neem (Azadirachta indica A. Juss) aqueous leaf extract on the growth, yield and disease control of a common vegetable plant tomato (Solanum lycopersicum L.). The neem extract increased shoot height, number of branches, number of leaves, number of buds, number of flowers and number of fruits of tomato plant over controls in different treatments. Numbers of diseases were calculated as percentage and disease/plant. The percentage of reduction of disease was calculated after the spray of neem extract on plants. Neem extract was found effectively in controlling canker (50.32%), early blight (55.12%), wilt (59.45%), leaf spot (55.48%), fruit spot (41.93%), blossom end rot (40.86%) and sun scald (25.61%) in comparison to controls under field condition. Thus, biopesticides can contribute in reducing use of chemical pesticides and subsequently minimize its hazards to the environment and human health

IMMUNOSTIMULATORY EFFECT OF OCIMUM SANCTUM LINN. LEAF EXTRACT IN CLARIAS BATRACHUS LINN

Objective: Recently, there has been increased interest in the immune stimulating function of some herbs in aquaculture. The phytomedicines provide a cheaper source for treatment and greater accuracy than chemotherapeutic agents without causing toxicity. Many studies have proved that herbal additives enhanced the growth of fishes and protected them from various diseases. The herbs are not only safe for consumers but also widely available throughout the world and they also have a significant role in aquaculture. Certain medicinal plants are believed to promote positive health and maintain organic resistance against infection by re-establishing body equilibrium and conditioning the body tissues.Methods: The aerial parts of Ocimum sanctum Linn. were extracted with double distilled water and then extracts were screened for their immunomodulatory effects on Clarias batrachus. Haematological and biochemical studies were done on specific and nonspecific levels after administering the extracts for 15 and 30 days.Result: Our results showed that there is no significant decrease in the amount of glucose and cholesterol at concentration 2.5% but there is a significant reduction in glucose amount at 5% in comparison to control. But a significant increase was seen; the RBC, WBC, serum protein and globulin at 2.5% and 5% concentrations of crude extracts in both the 15 and 30 days of treatments in the blood of the fish. It may be due to the presence of phenolic compounds like tannins, saponin, flavonoids, steroid, terpenoids, eugenol, caryophylline, cardiac glycerides etc. Conclusion: Based on the results it is appropriate to conclude that the plant extract of Ocimum sanctum may act as a potent Immunostimulant in Clarias batrachus Linn.Keywords: Immunostimulants, Phytochemicals, Clarias batrachus Linn, Ocimum sanctum Linn

Immunomodulatory effect of Ocimum gratissimum Linn. leaf extract on a Common Fish Clarias batrachus Linn.

The use of immunostimulants for the prevention of disease in fishes is considered as an attractive and promising area in the field of aquaculture. Immunostimulants are valuable for the prevention and control of fish diseases in aquaculture as they represent an alternative and supplementary treatment to vaccination. They also have additional effects such as growth enhancement and increase in the survival rates of the fishes under stress. Certain medicinal plants are believed to promote positive health and maintain organic resistance against infection by re-establishing body equilibrium and conditioning the body tissues. The present study was designed to evaluate the immunostimulant potential of crude extract of Ocimum gratissimum leaf on fish Clarius batracus in both specific and non specific levels. Our results showed that there is not a significant decrease in the amount of Glucose and cholesterol at concentration 2.5% but there is a significant reduction in glucose amount at 5% in comparison to control. But a significant increase was seen the RBC, WBC, Serum protein and globulin at 2.5% and 5% concentrations of crude extracts in both the 15 and 30 days of treatments in the blood of the fish. It may be due to the presence phenolic compounds like flavonoids, terpenoids steroids, alkaloids etc. Based on the results it is appropriate to conclude that the plant extract of Ocimum gratissimum may act as a potent Immunostimulant in Clarias batrachus