金属组分对TiO_2光催化氧化NO_2^-反应的影响

Effect of Metal Ions on TiO_2 Photocatalytic Oxidation of NO_2^-

研究了悬浮体系中金属组分Ag(Ⅰ )、Fe(Ⅲ )、Mn(Ⅶ )、Ce(Ⅳ )和Fe(Ⅲ )的浓度、体系 pH值对NO-2 TiO2 光催化氧化反应的影响。结果发现 ,金属组分对NO-2 TiO2 光催化氧化反应的协同催化能力取决于组分的电子俘获能力及在TiO2 表面的吸附能力 ,俘获电子能力强且在TiO2 表面有适度吸附时 ,其协同光催化能力较强。Fe(Ⅲ )在组分质量比大于TiO2 催化剂的 0 2 5 %及体系pH =4的条件下具有较强的协同催化能力。Ce(Ⅳ )对TiO2 光催化氧化NO-2 有明显的抑制作用。

The effects Ag(Ⅰ), Fe(Ⅲ), Mn(Ⅶ) and Ce(Ⅳ) concentrations and pH value on the photocatalytic reaction of NO- 2 in TiO 2 suspension system were studied. The results showed that most of the metal ions studied have stronger synergistic catalytic property, among them the Fe(Ⅲ) in mass fraction greater than 0.25% of TiO 2 and acidity of the system pH=4 showed considerably stronger synergistic catalytic property, and Ce(Ⅳ) showed an obvious inhibition effect on the TiO 2 photocatalytic oxidation of NO- 2.