以枫叶为生物模板合成了由纳米颗粒构成的分级多孔氧化铈材料. 采用场发射电子显微镜(FESEM)、透射电子显微镜(TEM)和氮气脱吸附技术表征了材料的独特生物形态微结构, 其仿生结构是由复制气孔得到的微米孔和复制细胞孔得到的2~4 nm的小孔构成. 通过广角X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)和BET计算发现多孔氧化铈具有很小的晶粒(6~8 nm)和较大的比表面积(64.4 m2/g). 利用化学储氧量(OSC)评价了样品催化性能, 结果表明: 分级多孔氧化铈比无孔氧化铈含有更多的表面活性氧. 当将材料用于酸性品红脱色反应, 由于分级多孔氧化铈材料的颗粒小, 比表面积大和化学储氧量高, 其在染料废水净化处理时具有较好的催化活性和吸附能力, 到300 min时脱色率可达到100%.
Hierarchical porous ceria with nanocrystalline was successfully synthesized using maple leaf as a biotemplate. Unique biomorphic microstructures were characterized by Field Emission Scanning Electron Microscope (FESEM), transmission electron microscope (TEM) and nitrogen absorption-desorption technique. The obtained ceria material shows the repetitious biomimetic structure consisting of the stoma porous about several μm and nanopores with 2-4 nm apertures. The small crystal grain (6-8 nm) and the high specific surface area (64.4 m2/g) of porous CeO2 are detected by wide-angle X-ray diffraction (XRD), high resolution TEM (HRTEM) and the BET method. The catalytic property is evaluated by the oxygen storage/release capacity (OSC). The test confirms that hierarchical porous material possesses more surface active oxygen than nonporous ceria does. While the concentration of acid fuchsine is 40 mg/L, the porous sample has a higher decoloring rate in a shorter time than others. The decoloring rate can reach 100% after decolored for 300min. The investigation infers that the hierarchical porous ceria exhibits better catalytic activity and higher adsorptive capacity in dye wastewater purification due to smaller crystallite size, higher surface area and enhanced OSC.
参考文献
| [1] | |
| [2] | |
| [3] | Li X Z, Chen Z G, Chen J Q, et al. Studies of process and mechanism for preparing nano-sized CeO2 powders via homogeneous precipitation in alcohol-water solvent. J. Rare Earths, 2005, 23(Suppl.): 321-323.[2] 李霞章, 陈 杨, 陈志刚, 等. 纳米CeO2颗粒的制备及其化学机械抛光性能研究. 摩擦学学报, 2007, 27(1): 1-4.[3] 徐光青, 郑治祥, 汤文明, 等(XU Guang-Qing, et al). S2-掺杂对Ce3+-SiO2材料发光性能的影响. 硅酸盐学报(Journal of the Chinese Ceramic Society), 2007, 35(1): 10-15.[4] Tschope A, Birringer R. Oxyreduction studies on nanostructured cerium oxide. Nanostruct. Mater., 1997, 9(1-8): 591-594.[5] Palmqvist A E C, Johansson E M, Jaras S G, et al. Total oxidation of methane over doped nanophase cerium oxides. Catal. Lett., 1998, 56(6): 69-75.[6] Shuk P, Ramanujachary K V, Greenblatt M. New metal-oxide-type pH sensors. Solid State Ionics, 1996, 86-88(2): 1115-1120.[7] Yabe S, Yamashita M, Momose S, et al. Synthesis and UV-shielding properties of metal oxide doped ceria via soft solution chemical processes. Int. J. Inorg. Mater., 2001, 3(7): 1003-1008.[8] 陈志刚, 郭亭亭, 李霞章, 等. 凹凸棒土负载CeO2催化氧化处理亚甲基蓝染料废水. 功能材料, 2009, 40(10): 1709-1712.[9] 陈 丰, 李霞章, 陆晓旺, 等(CHEN Feng, et al). 凹凸棒石／CeO2复合纳米材料的合成、表征及催化性能. 硅酸盐学报(Journal of the Chinese Ceramic Society), 2009, 37(1): 52-56.[10] Li X Z, Chen F, Lu X W, et al. Modified-EISA synthesis of mesoporous high-surface area CeO2 and catalytic property for CO oxidation. J. Rare Earths, 2009, 27(6): 943-947.[11] Mori T, Drennan J, Wang Y R, et al. Influence of nano-structure on electrolytic properties in CeO2 based system. J. Therm. Anal. Calorim., 2002, 70(2): 309-319.[12] Velu S, Kapoor M P, Inagaki S, et al. Vapor phase hydrogenation of phenol over palladium supported on mesoporous CeO2 and ZrO2. Appl. Cata. A: General, 2003, 245(2): 317-331.[13] Chen I P, Lin S S, Wang C H, et al. CWAO of phenol using CeO2/&gamma |
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