Abstract：In the present research, Cu3Si/Si composite has been synthesized by the electrolysis the CuO and SiO2 mixture for 5 h in the molten CaCl2-NaCl electrolyte under the cell voltage of 2.8 V at 700 ℃. The mass ratio of CuO and SiO2 is 1:1. According to the thermodynamic calculation, CuO is preferentially reduced to metallic Cu at 700 ℃. SiO2 is electro-reduced at the SiO2/CaCl2-NaCl electrolyte/Cu three-phase reaction interface. The reduced Si can react with Cu spontaneously to produce Cu3Si. The newly-formed Cu3Si alloy acts as the new current collector to promote the electrolysis of SiO2. The morphology of Cu3Si/Si is the accumulation of the porous particles with the particle size of 0.1 ~ 1.9 μm, and the metallic silicon covers the surface of the Cu3Si alloy.
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2020, Vol. 27 