The specific surface area was measured using the Brunauer-Emmett-Teller (BET) method on an instrument (Tristar II Plus, Micromeritics) after treatment of all samples in a vacuum at 200°C for 2 hours. In addition, powder X-ray structure analysis (XRD) was performed using the Cu Kα line (λ= 0.15417nm, 40 kV, 30mA, RINT2100CMJ, Rigaku).