Photocatalytic application of hollow CuO microspheres with hierarchical dandelion-like structures synthesized by a simple template free approach

Photocatalyst involving conducting polymer doped with titanium dioxide, TiO2 hold a great efficiency for photocatalytic application. In present study, polyaniline (PAni) with different TiO2 content (10%, 20%, and 40%) has been successfully synthesized through template free method. Ultraviolet-visible (UV-vis), Fourier Transform Infrared (FTIR), Raman, and X-ray Powder Diffraction (XRD) characterizations of PAni-TiO2 nanocomposites confirmed the chemical structure of polymer composites was intact after doped with TiO2. Field Emission Scanning Electron Microscope (FESEM) investigation of PAni-TiO2 nanocomposites revealed the formation of nanorod/nanotube. PAni-TiO2(10%) showed the highest conductivity 2.48 × 10−2 S/cm as compared to those with 20% and 40% of TiO2 content. Photocatalytic properties of PAni-TiO2 were examined by degrading Reactive Black 5 (RB5) dye under visible light irradiation. PAni-TiO2(10%) showed the greatest degradation (96%) than that of TiO2 (10%). Due to synergistic effect between PAni and TiO2, it is capable of absorbing visible light more efficiently and decreasing the process of electron hole recombination. Photoluminescence (PL) analysis proved low efficiency of electron hole recombination of PAni-TiO2.

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Dimensionally-Controlled Hydrothermal Tm3+-doped Oxidic Nanocrystals and Their Photoluminescence Properties

MRS Proceedings ◽

10.1557/proc-1247-c04-15 ◽

2010 ◽

Vol 1247 ◽

Author(s):

Rocío Calderón-Villajos ◽

Carlos Zaldo ◽

Concepción Cascales

Keyword(s):

Single Crystals ◽

Fluorescence Lifetimes ◽

Photoluminescence Properties ◽

Reaction Conditions ◽

Hydrothermal Processes ◽

Bulk Single Crystals ◽

Template Free ◽

Reaction Media

AbstractControlled reaction conditions in simple, template-free hydrothermal processes yield Tm-Lu2O3 and Tm-GdVO4 nanocrystals with well-defined specific morphologies and sizes. In both oxide families, nanocrystals prepared at pH 7 reaction media exhibit photoluminescence in ∼1.95 μm similar to bulk single crystals. For the lowest Tm3+ concentration (0.2 % mol) in GdVO4 measured 3H4 and 3F4 fluorescence lifetimes τ are very near to τrad.

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Ti3C2-MXene/Bismuth Ferrite Nanohybrids for Efficient Degradation of Organic Dye and Colorless Pollutant

10.26434/chemrxiv.8192375.v1 ◽

2019 ◽

Author(s):

Ayesha Tariq ◽

M. Abdullah Iqbal ◽

S. Irfan Ali ◽

Muhammad Z. Iqbal ◽

Deji Akinwande ◽

...

Keyword(s):

Surface Area ◽

Low Cost ◽

Bismuth Ferrite ◽

Organic Dye ◽

Two Dimensional ◽

Electron Hole ◽

Photocatalytic Application ◽

Electron Hole Pair ◽

Pair Generation ◽

Photocatalytic Applications

Nanohybrids, made up of Bismuth ferrites/Carbon allotropes, are extensively used in photocatalytic applications nowadays. Our work proposes a nanohybrid system composed of Bismuth ferrite nanoparticles with two-dimensional (2D) MXene sheets namely, the BiFeO3 (BFO)/Ti3C2 (MXene) nanohybrid for enhanced photocatalytic activity. We have fabricated the BFO/MXene nanohybrid using simple and low cost double solvent solvothermal method. The SEM and TEM images show that the BFO nanoparticles were attached onto the MXene surface and in the inter-layers of two-dimensional (2D) MXene sheets. The photocatalytic application is tested for the visible light irradiation which showed the highest efficiency among all pure-BFO based photocatalysts, i.e. 100% degradation in 42 min for organic dye (Congo Red) and colorless aqueous pollutant (acetophenone) in 150 min, respectively. The present BFO-based hybrid system exhibited the large surface area of 147 m2g-1measured via Brunauer-Emmett-Teller (BET) sorption-desorption technique, and is found to be largest among BFO and its derivatives. Also, the photoluminescence (PL) spectra indicate large electron-hole pair generation. Fast and efficient degradation of organic molecules is supported by both factors; larger surface area and lower electron-hole recombination rate. The BFO/MXene nanohybrid presented here is a highly efficient photocatalyst compared to other nanostructures based on pure BiFeO3 which makes it a promising candidate for many future applications.

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A Solvent Free Synthetic Route for Cerium(IV) Metal-Organic Frame-works with UiO-66 Architecture and Their Photocatalytic Application

10.26434/chemrxiv.9199634.v1 ◽

2019 ◽

Author(s):

Matteo Campanelli ◽

Tiziana Del Giacco ◽

Filippo De Angelis ◽

Edoardo Mosconi ◽

Marco Taddei ◽

...

Keyword(s):

Density Functional ◽

Chemical Oxidation ◽

Solvent Free ◽

Cerium Ammonium Nitrate ◽

Benzylic Alcohols ◽

Near Ultraviolet ◽

Photocatalytic Application ◽

Activity Density ◽

Ultraviolet Light Irradiation ◽

Metal Organic

<div> A novel solvent-free synthesis for Ce-UiO-66 metal-organic frameworks (MOFs) is presented. The MOFs are obtained by simply grinding the reagents, cerium ammonium nitrate (CAN) and the carboxylic linkers, in a mortar for few minutes with the addition of a small amount of acetic acid (AcOH) as modulator (1.75 eq, o.1 ml). The slurry is then transferred into a 1 ml vial and heated at 120°C for 1 day. The MOFs have been characterized for their composition, crystallinity and porosity and employed as heterogenous catalysts for the photo-oxidation reaction of substituted benzylic alcohols to benzaldaldehydes under near ultraviolet light irradiation. The catalytic performances, such as yield, conversion and kinetics, exceed those of similar systems studied by chemical oxidation and using Ce-MOF as catalyst. Moreover, the MOFs were found to be reusable up to three cycles without loss of activity. Density functional theory (DFT) calculations gave an estimation of the band-gap shift due to the different nature of the linkers used and provide useful information on the catalytic activity experimentally observed. </div>

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Electrochemical Deposition of Polypyrrole Nanostructures for Energy Applications: A Review

Current Nanoscience ◽

10.2174/1573413715666190717113600 ◽

2020 ◽

Vol 16 (4) ◽

pp. 462-477 ◽

Cited By ~ 2

Author(s):

Patrizia Bocchetta ◽

Domenico Frattini ◽

Miriana Tagliente ◽

Filippo Selleri

Keyword(s):

Lithium Batteries ◽

High Performance ◽

Relevant Literature ◽

Chemical Parameters ◽

Energy Devices ◽

Energy Applications ◽

Physico Chemical ◽

Potential Applications ◽

Template Free ◽

Cathodic Polymerization

By collecting and analyzing relevant literature results, we demonstrate that the nanostructuring of polypyrrole (PPy) electrodes is a crucial strategy to achieve high performance and stability in energy devices such as fuel cells, lithium batteries and supercapacitors. In this critic and comprehensive review, we focus the attention on the electrochemical methods for deposition of PPy, nanostructures and potential applications, by analyzing the effect of different physico-chemical parameters, electro-oxidative conditions including template-based or template-free depositions and cathodic polymerization. Diverse interfaces and morphologies of polymer nanodeposits are also discussed.

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