能源化学(英文版)

能源化学(英文) ›› 2013, Vol. 22 ›› Issue (6): 819-825.

• ARTICLES •    下一篇

Nano Si preparation by constant cell voltage electrolysis of FFC-Cambridge Process in molten CaCl2

Ji Zhaoa,b, Shengmei Lua, Linyan Hua, Can Lia   

  1. a. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, Liaoning, China;
    b. University of Chinese Academy of Sciences, Beijing 100049, China
  • 收稿日期:2013-03-07 修回日期:2013-05-09 发布日期:2013-11-28
  • 通讯作者: Can Li
  • 基金资助:

    This work was supported by the Solar Energy Initiative of the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KGCX2-YW-395).

Nano Si preparation by constant cell voltage electrolysis of FFC-Cambridge Process in molten CaCl2

Ji Zhaoa,b, Shengmei Lua, Linyan Hua, Can Lia   

  1. a. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, Dalian 116023, Liaoning, China;
    b. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2013-03-07 Revised:2013-05-09 Published:2013-11-28
  • Supported by:

    This work was supported by the Solar Energy Initiative of the Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KGCX2-YW-395).

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摘要： Using FFC-Cambridge Process to prepare Si from SiO2 is a promising method to prepare nanostructured and highly pure silicon for solar cells. However, the method still has many problems unsolved and the controlling effect of the cell voltage on silicon product is not clear. Here we report in this article that nano cluster-like silicon product with purity of 99.95% has been prepared by complete conversion of raw material SiO2, quartz glass plate, using constant cell voltage electrolysis FFC-Cambridge Process. By analysis of XRD, EDS, TEM, HRTEM and ICP-AES as well as the discussion from the thermodynamics calculation, the morphology and components of the product based on the change of cell voltage are clarified. It is clear that pure silicon could be prepared at the cell voltage of 1.7-2.1 V in this reaction system. The silicon material have cluster-like structure which are made of silicon nanoparticles in 20-100 nm size. Interestingly, the cluster-like nano structure of the silicon can be tuned by the used cell voltage. The purity, yield and the energy cost of silicon product prepared at the optimized cell voltage are discussed. The purity of the silicon product could be further improved, hence this method is promising for the preparation of solar grade silicon in future.

关键词: silicon, nanostructures, molten salt electrochemistry, solar grade Si, FFC-Cambridge Process

Abstract: Using FFC-Cambridge Process to prepare Si from SiO2 is a promising method to prepare nanostructured and highly pure silicon for solar cells. However, the method still has many problems unsolved and the controlling effect of the cell voltage on silicon product is not clear. Here we report in this article that nano cluster-like silicon product with purity of 99.95% has been prepared by complete conversion of raw material SiO2, quartz glass plate, using constant cell voltage electrolysis FFC-Cambridge Process. By analysis of XRD, EDS, TEM, HRTEM and ICP-AES as well as the discussion from the thermodynamics calculation, the morphology and components of the product based on the change of cell voltage are clarified. It is clear that pure silicon could be prepared at the cell voltage of 1.7-2.1 V in this reaction system. The silicon material have cluster-like structure which are made of silicon nanoparticles in 20-100 nm size. Interestingly, the cluster-like nano structure of the silicon can be tuned by the used cell voltage. The purity, yield and the energy cost of silicon product prepared at the optimized cell voltage are discussed. The purity of the silicon product could be further improved, hence this method is promising for the preparation of solar grade silicon in future.

Key words: silicon, nanostructures, molten salt electrochemistry, solar grade Si, FFC-Cambridge Process