Preparation and Photocatalysis Properties of TiO2/Graphene Nanocomposites

2012 ◽  
Vol 430-432 ◽  
pp. 1005-1008
Author(s):  
Dong Fang Wang ◽  
Da Chen ◽  
Guang Xing Ping ◽  
Chao Wang ◽  
Hai Zhen Chen ◽  
...  

In this work, a novel photocatalyst with excellent photocatalytic activities was developed by the combination of TiO2 with graphene oxide (GO). GO was firstly prepared by the chemical oxidation of graphite through Hummers method and the subsequent dispersion and exfoliation in water. Then, GO and P25 nanoparticles (commercial TiO2) were used as raw materials to synthesize TiO2/graphene (TiO2/GE) nanocomposites by using a one-step solvothermal method. TEM images clearly showed that TiO2 nanomaterials (the size of about 15~20 nm) were distributed well onto the two-dimensional (2D) graphene sheets, indicating the formation of TiO2/GE nanocomposites. XRD results indicated that TiO2/GE nanocomposites exhibited TiO2 crystalline phase structure. Meanwhile, it was demonstrated from the methylene blue (MB) photodegradation results that TiO2/GE nanocomposites possessed excellent photocatalytic activities with potential applications.

2017 ◽  
Vol 10 (06) ◽  
pp. 1750075 ◽  
Author(s):  
Xingping Wu ◽  
Aiping Zhu ◽  
Zhaodong Nan

Fe3O4 hollow microspheres with good dispersibility and high saturation magnetization were synthesized through a facile one-step solvothermal method. The formation mechanism of the hollow structure was studied by taking time-dependent experiments. Porous [Formula: see text]-FeOOH and [Formula: see text]-Fe2O3 nanosheets were firstly fabricated. Fe3O4 solid spheres aggregated by small particles were obtained from the transition of [Formula: see text]-FeOOH and [Formula: see text]-Fe2O3. Finally, the solid sphere is transferred to hollow sphere through Ostwald ripening. The maximum saturation magnetization of the hollow spheres is [Formula: see text][Formula: see text]emu/g, which is higher than some results reported in references. The Fe3O4 hollow spheres show potential applications in microwave absorption and photocatalysis.


2013 ◽  
Vol 669 ◽  
pp. 360-365
Author(s):  
Xu Zou ◽  
Bing Bing Liu ◽  
Wei Wu ◽  
Dong Mei Li ◽  
Quan Jun Li ◽  
...  

We fabricated mono-dispersed hollow waxberry shaped ß-quartz GeO2by a facile one-step synthesis in emulsion at room temperature. TEM images indicated that hollow waxberry shaped GeO2were consisted of nano-sphere whose average size were estimated to be 20 nm. The growth mechanism and optical properties of the products were also investigated. The possible formation mechanism of the hollow interior is proposed as the Ostwald ripening. The optical properties of the ß-GeO2nanoparticles with hollow shapes were also studied with photoluminescence spectrum, which reveals a broad emission, suggesting potential applications in electronic and optoelectronic nanodevices. These attractive results provide us a new simple method further used to fabricate other specific hollow structure and indicate hollow waxberry shaped GeO2may have potential applications in light-emitting nanodevices.


2016 ◽  
Vol 42 (1) ◽  
pp. 110-115 ◽  
Author(s):  
S. Asghar Khayatian ◽  
Ahmad Kompany ◽  
Nasser Shahtahmassebi ◽  
A. Khorsand Zak

2021 ◽  
Author(s):  
Qiao Chen ◽  
Xuefang Lan ◽  
Guihua Zhu ◽  
Lili Wang ◽  
Jinsheng Shi

Abstract Construction of heterojunction and decoration of cocatalyst are two vital strategies to accelerate migration of charge carriers. However, the fabrication routs of multi-composites are usually complex and expensive. In this work, Bi2O2CO3/Bi2O3/Bi ternary composite was fabricated via a facile one-step redox reaction. Ethylene glycol was selected as the solvent during the whole reaction process. Moreover, ethylene glycol as an excellent reductant can reduce Bi3+ into metallic Bi0 and itself is oxidized to CO32-, which would react with Bi2O3 to generate Bi2O2CO3 without additional carbon source. Component proportions in ternary composites were optimized by the control of the ratios of raw materials. Under simulate solar light, Bi-based ternary composites exhibited enhanced photodegradation efficiencies for multifarious pollutants in comparison with single and binary samples. The enhanced photocatalytic activities were ascribed to accelerated migration rate of charge carriers owing to the construction of heterojunction and decoration of cocatalyst.


Nanomaterials ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1556 ◽  
Author(s):  
Zhao ◽  
Liu ◽  
Zhang ◽  
Zhang ◽  
Liao ◽  
...  

The adjustment of the emitting wavelength of carbon dots (CDs) is usually realized by changing the raw materials, reaction temperature, or time. This paper reported the effective synthesis of multicolor photoluminescent CDs only by changing the solvent in a one-step solvothermal method, with 1,2,4,5-tetraaminobenzene as both the novel carbon source and nitrogen source. The emission wavelengths of the as-prepared CDs ranged from 527 to 605 nm, with quantum yields (QYs) reaching 10.0% to 47.6%, and it was successfully employed as fluorescence ink. The prepared red-emitting CDs (R-CDs, λem = 605 nm) and yellow-emitting CDs (Y-CDs, λem = 543 nm) were compared through multiple characterization methods, and their luminescence mechanism was studied. It was discovered that the large particle size, the existence of graphite Ns, and oxygen-containing functional groups are beneficial to the formation of long wavelength-emitting CDs. Y-CDs responded to crystal violet, and its fluorescence could be quenched. This phenomenon was thus employed to develop a detection method for crystal violet with a linear range from 0.1 to 11 µM and a detection limit of 20 nM.


2011 ◽  
Vol 130-134 ◽  
pp. 1270-1275 ◽  
Author(s):  
Bin Xia Yuan ◽  
Hong Hong Fu ◽  
Wei Ling Luan

A flask solvothermal method was firstly utilized to facile synthesize greigite Fe3S4micro-crystals (MCs). By using iron nitrate, element sulfur as raw materials as well as oleylamine as the solvent, high yield of Fe3S4MCs with hexahedron microstructure was obtained. In addition, it was found that it was easily to achieve transformation between Fe3S4and Fe7S8through changing reaction temperatures and iron-sulfur ratios. The several different morphologies of Fe3S4MCs were obtained by using other sulfur sources. The synthetic approach demonstrated here could be of great potential for the controlled synthesis of other metal chalcogenides.


Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 202
Author(s):  
Yexin Dai ◽  
Jie Ding ◽  
Jingyu Li ◽  
Yang Li ◽  
Yanping Zong ◽  
...  

In this work, reduced graphene oxide (rGO) nanocomposites doped with nitrogen (N), sulfur (S) and transitional metal (Ni, Co, Fe) were synthesized by using a simple one-step in-situ hydrothermal approach. Electrochemical characterization showed that rGO-NS-Ni was the most prominent catalyst for glucose oxidation. The current density of the direct glucose alkaline fuel cell (DGAFC) with rGO-NS-Ni as the anode catalyst reached 148.0 mA/cm2, which was 40.82% higher than the blank group. The DGAFC exhibited a maximum power density of 48 W/m2, which was more than 2.08 folds than that of blank group. The catalyst was further characterized by SEM, XPS and Raman. It was speculated that the boosted performance was due to the synergistic effect of N, S-doped rGO and the metallic redox couples, (Ni2+/Ni3+, Co2+/Co3+ and Fe2+/Fe3+), which created more active sites and accelerated electron transfer. This research can provide insights for the development of environmental benign catalysts and promote the application of the DGAFCs.


2021 ◽  
Vol 503 ◽  
pp. 111431
Author(s):  
Xin Yu ◽  
Qingge Feng ◽  
Dachao Ma ◽  
Haiying Lin ◽  
Zheng Liu ◽  
...  

2021 ◽  
pp. 152808372110242
Author(s):  
Kadir Bilisik ◽  
Mahmuda Akter

In this paper, graphene, graphene/matrix, and graphene/fiber nanocomposites, including their synthesis process, fabrication, properties, and potential applications, were reviewed. It was found that several synthesis techniques for nanographene were developed, such as liquid-phase exfoliation and chemical vapor deposition. In addition, some fabrication processes of graphene/matrix and graphene/fiber-based nanocomposites were made, including in-situ polymerization, nanostitching in that single layer nano graphene plate could be interconnected by means of carbon nanotube stitching, resin transfer molding, and vacuum-assisted resin transfer molding. Several properties, including mechanical, thermal, and electrical, on the graphene nanoplatelets materials were summarized in this review paper. It was realized that graphene, graphene/matrix, and graphene/fiber nanocomposites have extraordinary mechanical, thermal, and electrical properties used in advanced engineering applications, including soft robotics, microelectronics, energy storage, biomedical and biosensors as well as textile industry.


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