Jiangtao Wang

Government of the People's Republic of China, Peping, Beijing, China

Are you Jiangtao Wang?

Claim your profile

Publications (10)38.99 Total impact

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Defects on diamond surface have a profound effect on certain properties of the diamond, enabling these properties to be tailored to the specific needs of important applications. A simple and practical method is described to repair the diamond particles with surface defects. The low grade diamond particles were repaired by hotfilament chemical vapor deposition with low carbon concentration in feed gases, and the defects on the surfaces disappeared because of the simple film formation and homoepitaxial growth mechanism during the CVD process. This efficient and simple method provides a way to extend its useful life during the actual application.
    Full-text · Article · Nov 2014 · Powder Technology
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Tungsten carbide porous films have been prepared by hot filament chemical vapor deposition with carbonized tungsten filaments as precursors. The structural properties and morphologies of the nanofilms were characterized by XRD, SEM and Raman. There are many nanocones and channels in the surface. A possible formation mechanism of the structure was proposed. And the contact angle measurements show that the films exhibit excellent hydrophilicity, especially the film after the treatment by hydrogen has a contact angle of 8.6 °. The high roughness and chemical composition on the surface are responsible for its hydrophilicity. Therefore, this film maybe has potential as electro-catalyst and electrocatalyst support.
    Full-text · Article · Jan 2014 · Materials Letters
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A new microwave plasma process is developed to refine and purify metallurgical grade silicon (MG-Si) effectively. Inductively coupled plasma-atomic emission spectrometry analysis (ICP-AES) indicates that the concentrations of impurities in silicon decrease significantly in the process, particularly for phosphorus, whose average removal rate is close to 100% after microwave plasma treatment of only 5 min. The underlying mechanisms of the ultra-high removal rate of impurity atoms are discussed in detail in this paper. The photoresponse switching behavior of n+-Si wafers that are made of as-purified silicon provides further evidence for the unique advantage arising from the use of microwave plasma in the purification of MG-Si.
    Full-text · Article · Jan 2013 · Separation and Purification Technology
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Highly transparent nanocrystalline TiO2 films have been fabricated by electrospinning (ES) technique based on a transmutation process from as-spun nanofibers with an appropriate amount of tri-ethanolamine (TEOA) added to the precursor. A possible evolution mechanism of the transparent nanocrystalline TiO2 films is proposed. It is found that the films prepared via transmutation from electrospun nanofibers possess rich bulk oxygen vacancies (BOVs, PL band at 621-640 nm) by using photoluminescence (PL) spectroscopy. Contrastively, the dominant peak in PL spectrum of the spin-coated film is the emission from surface oxygen vacancies (SOVs, PL band at 537-555 nm). The electrospun TiO2 films with rich BOVs induces large open-circuit voltage (Voc) and fill factor (FF) improvements in dye-sensitized solar cells (DSCs), and thus a large improvement of energy conversion efficiency (η). In addition, these performance advantages are maintained for a double-layer cell with a doctor-bladed ∼7 μm top layer (P25 nanometer TiO2, Degussa) and an electrospun ∼3 μm bottom layer. The double-layer cell yields a high η of 6.01%, which has increased by 14% as compared with that obtained from a 10 μm thick P25 film.
    Full-text · Article · Sep 2012 · Journal of Power Sources
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Highly transparent nanocrystalline TiO2 films have been fabricated by electrospinning (ES) technique based on a transmutation process from as-spun nanofibers with an appropriate amount of tri-ethanolamine (TEOA) added to the precursor. A possible evolution mechanism of the transparent nanocrystalline TiO2 films is proposed. It is found that the films prepared via transmutation from electrospun nanofibers possess rich bulk oxygen vacancies (BOVs, PL band at 621-640 nm) by using photoluminescence (PL) spectroscopy. Contrastively, the dominant peak in PL spectrum of the spin-coated film is the emission from surface oxygen vacancies (SOVs, PL band at 537-555 nm). The electrospun TiO2 films with rich BOVs induces large open-circuit voltage (Voc) and fill factor (FF) improvements in dye-sensitized solar cells (DSCs), and thus a large improvement of energy conversion efficiency (η). In addition, these performance advantages are maintained for a double-layer cell with a doctor-bladed ∼7 μm top layer (P25 n
    Full-text · Article · Sep 2012 · Journal of Power Sources
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Single-phase tungsten carbide nanopillar arrays have been prepared by hot filament chemical vapor deposition with carbonized tungsten filaments as precursors. The structural properties and morphologies of the nanopillar arrays were characterized by XRD, SEM and HRTEM, respectively. A possible formation mechanism for the morphology was proposed. Moreover, the field emission properties of the nanopillar arrays have been studied. The Fowler–Nordheim plot of the nanopillar arrays shows an interesting linear dependence demonstrating their suitability as emitters. The nanopillar arrays show remarkable stability for several hours at a current intensity of about 5.6 × 10−7 A at 2000 V with a distance between the anode and sample of 150 μm.
    Full-text · Article · Aug 2012 · RSC Advances
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A high-efficiency photoelectrode for dye-sensitized solar cells (DSSCs) should combine the advantageous features of fast electron transport, slow interfacial electron recombination and large specific surface area. However, these three requirements usually cannot be achieved simultaneously in the present state-of-the-art research. Here we report a simple procedure to combine the three conflicting requirements by using porous SnO2 nanotube-TiO2 (SnO2 NT-TiO2) core-shell structured photoanodes for DSSCs. The SnO2 nanotubes are prepared by electrospinning of polyvinyl pyrrolidone (PVP)/tin dichloride dihydrate (SnCl2[middle dot]2H2O) solution followed by direct sintering of the as-spun nanofibers. A possible evolution mechanism is proposed. The power conversion efficiency (PCE) value of the SnO2 NT-TiO2 core-shell structured DSSCs ([similar]5.11%) is above five times higher than that of SnO2 nanotube (SnO2 NT) DSSCs ([similar]0.99%). This PCE value is also higher than that of TiO2 nanoparticles (P25) DSSCs ([similar]4.82%), even though the amount of dye molecules adsorbed to the SnO2 NT-TiO2 photoanode is less than half of that in the P25 film. This simple procedure provides a new approach to achieve the three conflicting requirements simultaneously, which has been demonstrated as a promising strategy to obtain high-efficiency DSSCs.
    Full-text · Article · Jun 2012 · Nanoscale
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A high-efficiency photoelectrode for dye-sensitized solar cells (DSSCs) should combine the advantageous features of fast electron transport, slow interfacial electron recombination and large specific surface area. However, these three requirements usually cannot be achieved simultaneously in the present state-of-the-art research. Here we report a simple procedure to combine the three conflicting requirements by using porous SnO(2) nanotube-TiO(2) (SnO(2) NT-TiO(2)) core-shell structured photoanodes for DSSCs. The SnO(2) nanotubes are prepared by electrospinning of polyvinyl pyrrolidone (PVP)/tin dichloride dihydrate (SnCl(2)·2H(2)O) solution followed by direct sintering of the as-spun nanofibers. A possible evolution mechanism is proposed. The power conversion efficiency (PCE) value of the SnO(2) NT-TiO(2) core-shell structured DSSCs (∼5.11%) is above five times higher than that of SnO(2) nanotube (SnO(2) NT) DSSCs (∼0.99%). This PCE value is also higher than that of TiO(2) nanoparticles (P25) DSSCs (∼4.82%), even though the amount of dye molecules adsorbed to the SnO(2) NT-TiO(2) photoanode is less than half of that in the P25 film. This simple procedure provides a new approach to achieve the three conflicting requirements simultaneously, which has been demonstrated as a promising strategy to obtain high-efficiency DSSCs.
    Full-text · Article · May 2012 · Nanoscale
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A high-efficiency photoelectrode for dye-sensitized solar cells (DSSCs) should combine the advantageous features of fast electron transport, slow interfacial electron recombination and large specific surface area. However, these three requirements usually cannot be achieved simultaneously in the present state-of-the-art research. Here we report a simple procedure to combine the three conflicting requirements by using porous SnO 2 nanotube–TiO 2 (SnO 2 NT–TiO 2) core–shell structured photoanodes for DSSCs. The SnO 2 nanotubes are prepared by electrospinning of polyvinyl pyrrolidone (PVP)/tin dichloride dihydrate (SnCl 2 $2H 2 O) solution followed by direct sintering of the as-spun nanofibers. A possible evolution mechanism is proposed. The power conversion efficiency (PCE) value of the SnO 2 NT–TiO 2 core–shell structured DSSCs ($5.11%) is above five times higher than that of SnO 2 nanotube (SnO 2 NT) DSSCs ($0.99%). This PCE value is also higher than that of TiO 2 nanoparticles (P25) DSSCs ($4.82%), even though the amount of dye molecules adsorbed to the SnO 2 NT–TiO 2 photoanode is less than half of that in the P25 film. This simple procedure provides a new approach to achieve the three conflicting requirements simultaneously, which has been demonstrated as a promising strategy to obtain high-efficiency DSSCs.
    Full-text · Article · Apr 2012
  • Source
    Erqing Xie · Jiangtao Wang · Chenguang Hou · Changhui Zhao
    [Show abstract] [Hide abstract]
    ABSTRACT: 本发明涉及一种氢氧焰等离子体提纯冶金级多晶硅粉体的方法,该方法包括以下步骤:(1)将冶金级硅粉进行超声清洗后,室温下晾干,得到预处理硅粉;(2)将预处理硅粉放入氢氧焰等离子体提纯装置内的送料槽中;(3)打开所述氢氧焰等离子体提纯装置内的氢氧焰产生装置,预产生3~5分钟,以使火焰稳定;(4)打开送料槽,通过调节氢氧焰等离子体提纯装置内的左右控制弹簧的伸长尺寸使斜坡与水平面的夹角为10~40度,此时硅粉颗粒均匀下落并均匀有序地通过火焰,即得提纯后的冶金级多晶硅粉体;该提纯后的冶金级多晶硅粉体落入玻璃容器,收集即可。本发明不但便于实现大规模的生产应用,而且有效降低了能耗及提纯成本,同时也降低了提纯的难度。
    Full-text · Patent · Jan 2011

Publication Stats

110 Citations
38.99 Total Impact Points

Institutions

  • 2014
    • Government of the People's Republic of China
      Peping, Beijing, China
  • 2012-2014
    • Lanzhou University
      • School of Physical Science and Technology
      Kao-lan-hsien, Gansu Sheng, China