Functional Nanomaterials Laboratory and Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry (TIPC), Chinese Academy of Sciences, Beijing 100190, China.
J Environ Sci (China). 2012;24(6):1117-24. doi: 10.1016/s1001-0742(11)60879-6.
Flaky and nanospherical birnessite and birnessite-supported Pt catalysts were successfully prepared and characterized by means of Xray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and N2 adsorption-desorption. Effects of the birnessite morphology and Pt reduction method on the catalytic activity for the complete oxidation of formaldehyde (HCHO) were investigated. It was found that flaky birnessite exhibited higher catalytic activity than nanospherical birnessite. The promoting effect of Pt on the birnessite catalyst indicated that the reduction method of the Pt precursor greatly influenced the catalytic performance. Flaky birnessite-supported Pt nanoparticles reduced by KBH4 showed the highest catalytic activity and could completely oxidize HCHO into CO2 and H20 at 50 degreesC, whereas the sample reduced using H2-plasma showed lower activity for HCHO oxidation. The differences in catalytic activity of these materials were jointly attributed to the effects of pore structure, surface active sites exposed to HCHO and the dispersion of Pt nanoparticles.
片状和纳米球形水钠锰矿以及负载在水钠锰矿上的 Pt 催化剂通过 X 射线衍射（XRD）、透射电子显微镜（TEM）、能谱（EDS）和 N2 吸附-脱附进行了成功的制备和表征。研究了水钠锰矿形态和 Pt 还原方法对甲醛（HCHO）完全氧化催化活性的影响。结果表明，片状水钠锰矿表现出比纳米球形水钠锰矿更高的催化活性。Pt 对水钠锰矿催化剂的促进作用表明，Pt 前体的还原方法对催化性能有很大影响。用 KBH4 还原的片状水钠锰矿负载的 Pt 纳米颗粒表现出最高的催化活性，可在 50°C 下将 HCHO 完全氧化为 CO2 和 H20，而用 H2-等离子体还原的样品对 HCHO 氧化的活性较低。这些材料的催化活性差异归因于孔结构、暴露于 HCHO 的表面活性位和 Pt 纳米颗粒的分散性的影响。
