光催化沉积法制备Pd膜的改进及Pd膜性能表征

Improved photocatalytic deposition and characterization of palladium membranes

对光催化沉积法（PCD）制备Pd膜进行了改进，使含有TiO2与Pd^2＋的悬浮液膜层在多孔陶瓷膜表面形成液体薄膜，该薄膜在紫外光直接照射下发生光催化还原反应，烧结后得到含TiO2及Pd晶种的超薄膜层，用化学镀修饰得致密Pd膜．采用SEM、EDAX方法对所制的Pd膜表征结果表明，Pd膜厚度为5～6μm．在350～500℃和0.05～0．15MPa下进行气体渗透实验，当温度为450℃时，H2渗透系数为4.07×10^-6mol／（m^2·s·Pa），N2的渗透量检测不出，高温热循环测试表明该Pd膜致密且具有良好的热稳性．

In order to improve thin palladium membrane performance and simplify the preparation process, an improved photocatalytic deposition was developed. The key of the method was adding TiO2 powder into photocatalytic reactant solution and reducing Pd^2＋ into Pd in the suspension film on the interfacing support, instead of preparing a TiO2membrane in advance and then reducing Pd^2＋ on it, and modified Pd membrane with a thickness of 5 -6 μm was fabricated. The gas permeation experiments were conducted at 350 - 500 ℃ and 0. 05 - 0. 15 MPa. The hydrogen permeability and permeation selectivity of H2/N2 are 4. 07 × 10^-6 tool/（ m^2· s^- 1 · Pa） and almost infinite at 450 ℃ , respectively. Additionally, the Pd composite membrane shows a good thermodynamic stability.