Solvothermal Synthesis of Strontium Titanate Based Materials Designed For Efficient Visible Light Photocatalysis

The environmental problem and energy crisis, two main of global issues, will come soon on the earth. For the sustainable development of human life in the future, the great efforts should be devoted from now. Visible light responsive photocatalysts, one of semiconductor materials could be effectively used to convert the sun light energy into various applications, such as decomposition of pollutants. Visible-light-responsive photocatalysts are great beneficial because 43% of the whole solar energy is visible light, while only 4% is UV light1. Therefore, design to synthesize a photocatalyst with enhanced photocatalytic activity in visible light range is a highlight works. Here, the attention was concentrated mainly on design and synthesis of strontium titanate for efficient visible-light photocatalysis.

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The way forward for the modification of dye-sensitized solar cell towards better power conversion efficiency

Renewable and Sustainable Energy Reviews 74 (2017) 438–452

The power conversion efficiency (PCE) of TiO2-based dye-sensitized solar cells (DSSCs) could be enhanced by modification of photoanodes. The effective blocking layer addition, one-dimensional nanostructure architecture, and scattering material design are the most important approaches to provide the high PCE of DSSCs and are critically reviewed in this work. The blocking layer generated the energy barrier can suppress the recombination of an electron in photoanode. One-dimensional (1D) nanostructures of a nanorod, nanotube and nanowire, promote the enhanced electron transport of DSSCs. The PCE of 1D nanostructure based DSSCs can potentially be improved by incorporating high surface area TiO2 nanoparticles and constructing the multilayered 1D nanostructure arrays photoanodes. The scattering effect can be generated by mesoporous, core-shell and yolkshell materials with the sizes architecture corresponding to the wavelength of incident light, enhancing the light harvesting. The high efficiency of TiO2-based photoanodes could be realized by optimizing the composition, size of materials, and thickness of photoanodes.

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The highly active saddle-like Ag3PO4 photocatalyst under visible light irradiation

Catalysis Communications 85 (2016) 22–25

Saddle-like Ag3PO4 particles of tetrahedron structure were successfully synthesized using a co-precipitation method by mixingH3PO4 ethanol solution and AgNO3 ethanol aqueous solution, where the percentage of ethanol in AgNO3 ethanol aqueous solution was varied at 0, 50, 80, 90 and 100% (v/v). The photocatalytic performance of the synthesized samples was evaluated by photodegradation of Rhodamine B (RhB) under blue light irradiation (λ = 455 nm). The results showed that the morphology of the Ag3PO4 particles greatly changed depending on the ethanol content in the reaction solution. Excellent photocatalytic activity was observed at 80% (v/v) of ethanol, where the Ag3PO4 showed saddle-like morphology derived from the tetrahedron structure.

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Synthesis of Ag3PO4-polyvinyl alcohol hybrid microcrystal withenhanced visible light photocatalytic activity

Applied Surface Science 356 (2015) 226–231

The Ag3PO4/polyvinyl alcohol (Ag3PO4/PVA) hybrid photocatalysts were successfully synthesized usinga coprecipitation method using AgNO3, Na2HPO4·12H2O and PVA as starting materials. The productsemerged in a cubic (p-43n) structure. The photocatalytic performances for the decomposition of Rho-damine B (RhB) under the blue light irradiation strongly depended on PVA content. The excellentphotocatalytic activity may be due to the enhanced photo-induced charge separation brought on bythe strong interaction of PVA with Ag3PO4.

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Solvothermal synthesis and photocatalytic properties of chromium-doped SrTiO3 nanoparticles

Applied Catalysis B: Environmental 105 (2011) 206–210

Single phase of Cr-doped SrTiO3 (SrTi1−xCrxO3, x = 0–0.2) nanoparticles (15–20 nm) were successfully synthesized by themicrowave assisted-solvothermal synthesis method in KOH methanol oleic acid solution. The small amount of chromium doping (x = 0.005) resulted in excellent visible light photocatalytic activity up to the wavelength of = 627nm (red light LED). The high photocatalytic activity in the visible region was caused by generating the new absorption in the visible region.

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Visible light photocatalytic activity induced by the carboxyl group chemically bonded on the surface of SrTiO3

Applied Catalysis B: Environmental 102 (2011) 286–290

Nanocrystals of cubic perovskite SrTiO3 chemically adsorbed
carboxyl group on the surface could be synthesized by microwave assisted
solvothermal reactions in KOH methanol-oleic acid
solutions using Ti(OC3H7)4 and SrCl2·6H2O. The functional group
(–COO−) of oleic acid chemically bonded on the surface generated
new absorption in the visible region and induced visible light
responsive photocatalytic activity.

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Solvothermal synthesis of designed nonstoichiometric strontium titanate for efficient visible-light photocatalysis

Applied Physics Letters 97, 103102 2010

SrTiO3 powders with various Sr/Ti atomic ratios were synthesized by microwave-assisted
solvothermal reactions of SrCl2 and TiOC3H74 in KOH aqueous solutions. The nanoparticles of perovskite type SrTiO3 structure with the particle size of 30–40 nm were synthesized. The photocatalytic activity was determined by deNOx ability using light emitting diode lamps of various wavelengths such as 627 nm red, 530 nm green, 445 nm blue, and 390 nm UV. The photocatalytic activity significantly changed depending on the Sr/Ti atomic ratio, i.e., the strontium rich sample Sr/Ti atomic ratio1 showed excellent visible light responsive photocatalytic activity for the oxidative destruction of NO.

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