Time filter

Source Type

Du F.,Anhui University | Yang Q.,Anhui University | Qin T.,Anhui University | Li G.,Anhui University | And 2 more authors.
Solar Energy | Year: 2017

In this article, ternary oxides NiCo2O4 with morphologies of nanosheets, nanorods and nanoflowers have been synthesized by the thermal treatment of the precursors which were fabricated via a hydrothermal process. The materials were then used as counter electrodes (CEs) in dye-sensitized solar cells (DSSCs). The DSSCs equipped with NiCo2O4 nanoflowers CE achieved excellent power conversion efficiency (PCE) of 8.48%, which is higher than that of counter parts of NiCo2O4 nanosheets (3.57%), NiCo2O4 nanorods (6.84%) and Pt (8.11%) CEs. Transmission electron microscopy image shows that the NiCo2O4 nanoflowers have the best porous 3-dimensional spatial structure. This study offers a self-assembled synthetic route to prepare NiCo2O4 nanoflowers. The unique structure exhibits high efficient performance and excellent catalytic activity, which may open a new window to use ternary oxides for greatly extending potential applications in dye-sensitized solar cells and other related fields. © 2017 Elsevier Ltd


Xu H.,Anhui University | Xu H.,CAS Hefei Institutes of Physical Science | Hu J.,Dongguan University of Technology | Ren X.,CAS Hefei Institutes of Physical Science | And 2 more authors.
RSC Advances | Year: 2016

Graphene oxide (GO) has been proved to be very efficient for radionuclide enrichment. However, its potential performance for binary sorbate systems containing both a radionuclide and phosphate receives little attention. In this study, the mutual effects of Eu(iii) and phosphate on their co-removal processes by GO as a function of contact time, pH and temperature were investigated in detail. The results show that the presence of phosphate can enhance not only the removal amount of Eu(iii) but also the removal kinetics of Eu(iii) on GO surfaces, and vice versa. Both the external mass transfer and diffusion of solute inside GO are important for the Eu(iii) and phosphate co-removal rate. Evaluation of the thermodynamic parameters (ΔG0 < 0, ΔH0 > 0 and ΔS0 > 0) indicates the co-removal process is endothermic and spontaneous. The results of X-ray photoelectron spectroscopy (XPS) and zeta potential (ZP) analyses indicate that the oxygen-containing functional groups on GO surfaces play an important role in the co-removal process. This study provides a quantitative investigation of Eu(iii) and phosphate with GO, which can facilitate the assessment of GO as a potential adsorbent for Eu(iii) and phosphate simultaneous cleanup. © 2016 The Royal Society of Chemistry.


Yang X.,Anhui University | Yu X.,Anhui University | Li G.,Anhui University | Li G.,Anhui Key Laboratory of Information Materials and Devices
Journal of Materials Science: Materials in Electronics | Year: 2016

CeO2 nanorods have been successfully synthesized by a facile one-step hydrothermal synthesis route only using Na3PO4·6H2O as mineralizer without any surfactant or template. XRD, SEM, TEM, XPS, Raman scattering, Photoluminescence spectra and UV–vis were employed to characterize the samples. The results showed that all the samples have a fluorite cubic structure and there are Ce3+ ions and oxygen vacancies in the surface of non-doped CeO2 nanorods. The visible luminescence exhibits similar emission peaks of room temperature photoluminescence and the emission intensity increases with the increase of concentration of Nd ions and then decrease. The band gap decreases with the increase of dopant, Nd3+ ions result in an effective red shifting of the band gap. © 2016 Springer Science+Business Media New York


Yu X.,Anhui University | Yang X.,Anhui Key Laboratory of Information Materials and Devices | Li G.,Anhui University | Li G.,Anhui Key Laboratory of Information Materials and Devices
Journal of Materials Science: Materials in Electronics | Year: 2016

The photoluminescence (PL) property of CeO2/g-C3N4 mixed samples have been studied in recent years, but it is not attractive due to their lower PL emission. In this paper, a simple mixing-calcinations method was used to prepare CeO2/g-C3N4 mixed particles. In this paper, CeO2 particles were synthesized at two different temperatures (120 and 140 °C) by two-step method. The g-C3N4 powders were prepared by heating urea directly. Then, the two products were mixed together and annealed at 300 °C for 1 h by a simple mixing-calcinations method. It was found that the spindle and fascicular shapes of CeO2 were surrounded by lamellar g-C3N4 with porous surface. The strong emission and emission peaks shifting happened to CeO2/g-C3N4 particles, in which CeO2 was prepared at 120 °C, due to the mutual synergistic effect of CeO2 and g-C3N4. © 2016 Springer Science+Business Media New York


Shi W.,Anhui University | He H.,Anhui University | Zhang X.,Anhui University | Feng A.L.,Anhui University | And 2 more authors.
Materials Research Bulletin | Year: 2012

A co-precipitation reaction was used to prepare nanocrystal Gd 6WO 12:Eu 3+ and Gd 2WO 6:Eu 3+ red emitting phosphor powders with different Eu 3+ doping levels. It is found that under the same preparation conditions, different doping level leads to different crystal structures; Gd 6WO 12-like with a tetragonal lattice structure tends to be synthesized at low doping level (10-40 mol%) yet Gd 2WO 6-like with a monoclinic lattice structure easily to grow at high doping level (60-80 mol%). The strong red emission of 5D 0 → 7F 2 transitions at 620 nm was observed for all powders under either near ultraviolet or blue light excited and the most intense emission was obtained at the concentration of 40 mol%. This kind of powders might find their promising application to compensate the white LEDs for the lack of red light component and to improve rendering index. © 2012 Elsevier Ltd. All rights reserved.


Shi W.,Anhui University | Feng A.,Anhui University | Tang H.,Anhui University | Ding Z.,Anhui University | And 4 more authors.
Optical Materials | Year: 2013

A co-precipitation method was employed to prepare Eu3+-doped gadolinium tungstate and Y3Al5O12:Ce fluorescent powders. Eu3+-doped gadolinium tungstate phosphors can be effectively excited both by ultraviolet light at 395 nm and blue light at 465 nm and emit remarkably intense red emission at 613 nm with near line spectrum. Ce3+-doped YAG can also efficiently absorb this blue light and produce a broad band of luminescence centering at 540 nm. The red fluorescent powder and yellow fluorescent phosphor were then mixed together at different weight ratios. It is found that the emission spectra of the blended phosphors excited with blue light at 465 nm is the superposition of the two phosphors, which means that the mixture's emission can be tuned by controlling the weight ratios. These results demonstrated the possibility of using the blended phosphors to increase the color-rendering properties of white LEDs. © 2012 Elsevier B.V. All rights reserved.


Cheng X.H.,Anhui University | Xu H.F.,Anhui University | Wang Z.Z.,Anhui University | Zhu K.R.,Anhui University | And 3 more authors.
Materials Research Bulletin | Year: 2013

Pure phase VO2(A) nanorods were synthesized via the reduction of V2O5 by oxalic acid during the hydrothermal treatment. Two sets of samples were prepared by varying both system temperature and reaction time under a filling ratio of 0.40 for observing the formation and evolution of VO2(A) nanorods. Structures were characterized by X-ray diffraction, scanning and transmission electron microscopies, respectively. It was found that VO2(B) was firstly formed and then transformed into VO2(A) as the increasing system temperature or extending reaction time. An assembling and following crystal adjustment was proposed for explanation the formation process of VO2(A) from VO2(B). For VO2(A) nanorods, the phase transition temperature of 169.7 C was higher than that of the VO2(A) bulk, it might be ascribed to the lower crystallinity or nonstoichiometry in VO2(A) nanorods. VO 2 nanostructures with controllable phases and properties should find their promising applications in a single VO2 nanodevice. © 2013 Elsevier Ltd. All rights reserved.


Zhong Y.,Anhui University | Chen P.,Anhui University | Yang B.,Anhui University | Zuo X.,Anhui University | And 4 more authors.
Applied Physics Letters | Year: 2015

In this work, the perovskite-type La0.67Sr0.33MnO3 (LSMO) oxide with perfect crystallinity was synthesized via sol-gel method and used as low-cost platinum-free counter electrodes (CEs) for dye-sensitized solar cell (DSSCs). The electrochemical characterizations indicate that LSMO electrode possesses excellent electrocatalytic activity for the I3- reduction and excellent electrochemical stability in I-/I3- electrolyte system. The DSSC based on this counter electrode achieves an energy conversion efficiency (η) of 6.62%, which approaches 92.6% of the level obtained by using Pt as CE (η=7.15%). Theperovskite-type oxide is low-cost and can be massively produced via sol-gel method which is superior to the solvothermal method. This work makes an attempt to develop potential counter electrode materials in perovskite-type oxides, which can help reduce the cost of DSSCs and thereby encourage their fundamental research and commercial applications. © 2015 AIP Publishing LLC.


Sun Z.,Anhui University | Sun Z.,Anhui Key Laboratory of Information Materials and Devices | Jiang X.,Anhui University | Jiang X.,Chuzhou University | And 5 more authors.
Journal of Alloys and Compounds | Year: 2013

CuAlO2 (CAO) thin films with Al volume fraction of 1-5% were prepared by RF magnetron sputtering and were annealed at 1173 K for 4 h in the air. The microstructures, optical and hydrophily properties of the as-deposited films were studied. XRD measurement shows that all films are polycrystalline and present as Cu-Al-O phase. 3D profilometer measurement shows the minimum of surface roughness is 11.6 nm for 1%Al-CAO film, and the maximum is 38.6 nm for 5%Al-CAO film. The transmittance in the visible range decreases from 60% to 40% after the annealing process as a result of impurity and rough surface. The minimum value of average refractive index and extinction coefficient is about 1.41 and 0.031 for 1%Al-CAO film. The estimated direct band gaps of CAO films are 3.37-3.53 eV. CAO films changes from hydrophobicity to hydrophily after annealing, and water contact angle of the annealed film increases from 31.1° to 70.5°. © 2013 Elsevier B.V. All rights reserved.


He H.,Anhui University | He H.,Anhui Key Laboratory of Information Materials and Devices | Huang D.,Anhui University | Huang D.,Anhui Key Laboratory of Information Materials and Devices | And 4 more authors.
Solid State Communications | Year: 2012

Bi 2Te 3 nanosheets were prepared by the solvothermal method. The XRD diffraction patterns indicated that all the samples had a single hexagonal lattice structure. Both scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to characterize their size, morphology, and microstructure. The fabricated Bi 2Te 3 nanosheets showed obvious preferred growth orientations along the a-and b-axes. Based on experimental results for the typical thickness of the nanosheets, a possible phenomenological mechanism for the formation of the Bi 2Te 3 nanosheets was proposed considering the competition between gravity and Van der Waals forces. © 2012 Elsevier Ltd. All rights reserved.

Loading Anhui Key Laboratory of Information Materials and Devices collaborators
Loading Anhui Key Laboratory of Information Materials and Devices collaborators