采用溶胶-凝胶法制备F掺杂的Ti/SnO_2电极,用于水相中全氟辛酸(PFOA)的电氧化降解,实验考察了F或Sb掺杂、煅烧温度、氟掺杂量、老化时间及涂覆次数对PFOA降解效率的影响。结果表明,在煅烧温度为500℃,掺杂比Sn∶F=9∶0.25,老化时间10 d,涂覆20次的条件下,F掺杂的Ti/SnO_2电极性能最好,反应30 min对PFOA的降解率达98%;而在相同电解条件下,Sb掺杂Ti/SnO_2电极降解PFOA效率仅61.7%。因此,F掺杂可有效提高SnO_2电极性能,有效氧化降解PFOA。
The novel F-doped Ti / SnO_2 electrode prepared by a sol-gel process was used for electrochemical decomposition of persistent perfluorooctanoic acid( PFOA). The effects of doping elements like F or Sb,annealing temperature,F-doping amount,aging time,and dip coating times on the removal rate of PFOA were investigated. The optimal conditions included the introduction of F as the doping element,an annealing temperature of500 ℃,F-doping amount at the Sn ∶ F ratio of 9 ∶ 0. 25,10 days of aging time for the sol-gel solution,and 20 of dip coating time. Under these conditions,the removal rate of PFOA reached 98% after 30 min of degradation.However,the Ti / SnO_2-Sb electrode was able to remove only 61. 7% of PFOA under the same conditions. Therefore,the F-doping can effectively improve the electrooxidation performance of an SnO_2 electrode to degrade PFOA.