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Journal of Environmental Sciences 2024年第4期138卷 709-718页

作者： Shuo Hu Jianghao Zhang Xueyan Chen Xiaoxiao Qin Jinshui Yao Changbin Zhang School of Materials Science&Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Formaldehyde(HCHO)is a common indoor pollutant that is detrimental to human *** efficient removal has become an urgent demand to reduce the public health *** this work,Ag-MnO_(x)-based catalysts were prepared and activated under different atmosphere(i.e.,air,hydrogen(H_(2))and carbon monoxide(CO))for efficient oxidation of *** catalyst activated with CO(Ag/Mn-CO)displayed the highest activity among the tested samples with 90% conversion at 100℃ under a gas space velocity of 75,000 mL/(g_(cat)·hr).Complementary characterizations demonstrate that CO reduction treatment resulted in synergically regulated content of surface oxygen on support to adsorb/activate HCHO and size of Ag particle to dissociate oxygen to oxidize the adsorbed *** contrast,other catalysts lack for either abundant surface oxygen species or metallic silver with the appropriate particle size,so that the integrate activity is limited by one specific reaction *** study contributes to elucidating the mechanisms regulating the oxidation activity of Ag-based catalysts.

关键词： HCHO oxidation Ag-MnO_(x)-based catalyst Activation condition Synergic regulation surface oxygen Oxidized Ag

Tuning surface active oxygen of lanthanum oxide via partial dissolution and regrowth of crystallites

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Journal of Natural Gas Chemistry 2011年第5期20卷 483-486页

作者： Zhiming Gao, Huili Li Key Laboratory of Cluster Science, Ministry of Education of China Department of Chemistry, School of Science, Beijing Institute of Technology, Beijing 100081, China Key Laboratory of Cluster Science Ministry of Education of China Department of Chemistry School of Science Beijing Institute of Technology Beijing 100081 China

A commercial lanthanum oxide was modified into X%-La2O3 samples via partial dissolution and regrowth of crystallites, wherein the X value denotes the weight percent of the initial metal oxide powder dissolved by nitric acid. BET measurements and TEM observations indicate that the 20%-La2O3 sample has an increased specific surface area, relatively thin and small crystallites in size. TPD/TPR profiles also show that the 20%-La2O3 sample has more surface active oxygen than the 0%-La2O3 sample. Among the four X%-La2O3 samples, the highest activity for methane oxidation was obtained over the 20%-La2O3 sample. Therefore, the present work proves that the method of partial dissolution and regrowth of crystallites are effective to modify surface property of lanthanum oxide.

关键词： solid state reaction surface oxygen crystallite regrowth TPR metal oxide

Positively charged carbon electrocatalyst for enhanced power performance of L-ascorbic acid fuel cells

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Journal of Energy Chemistry 2016年第5期25卷 793-797页

作者： Myounghoon Choun Hye Jin Lee Jaeyoung Lee Electrochemical Reaction and Technology Laboratory School of Environmental Science and Engineering GIST Department of Chemistry and Green-Nano Materials Research Center Kyungpook National University Ertl Center for Electrochemistry and Catalysis Research Institute for Solar and Sustainable Energies (RISE) GIST

Carbon surface with large oxygen and carbon ratio(O/C) indicated an outstanding electro-catalytic activity toward L-ascorbic acid oxidation, compared to platinum group metals. However, interrelation of surface functional groups and its electro-catalytic activity is still unclear. In this paper, we prepared different levels of oxidized carbons by a simple acid treatment and investigated the correlation between the surface oxygen functional groups of acid-treated carbon and electro-catalytic activity in an electrooxidation of L-ascorbic acid. Positively charged carbon was demonstrated by lone pair electron of oxygen from valence band spectra study. It was revealed that the positively charged carbon, especially involved in carbonyl, showed enhanced the electro-catalytic activity through both better adsorption of negatively charged reactants and lowered LUMO by electronegativity of oxygen.

关键词： Vitamin-C electrooxidation Electronegativity Carbon Atomic charge surface oxygen

Effect　of　CeO_2　on　Crystal　Structures　and　Catalytic　Properties　of　the　Mn_2O_3　Catalysts

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Journal of Rare Earths 1994年第4期12卷 259-263页

作者：罗孟飞朱波袁贤鑫 Hangzhou Univ Hangzhou China

The manganese-cerium complex oxide catalysts were prepared by *** crystal structures,the desorption properties of surface oxygen and reducibility of these catalysts were investigated by means of X-ray diffraction analysis (XRD),temperature-programmed desopotion-mass spectrography (TPD-MS) and temperature-programmed reduction (TPR).The crystal structure of Mn-O and Mn-Ce-O catalysts are bixbyite-Mn2O3 and γ-Mn2O3 *** presence of CeO2 can not change the position of the feature peaks of Mn2O3 on the TPD or profiles,but can increase evidently the amount of the adsorbed surface oxygen,which are correlated with the catalytic activity for methanol *** activity of the catalyst is optimum when Mn/Ce atom ratio is 4:*** presence of CeO2 brings a change of the reducibility,which reveals that there is an interaction between Mn2O3 and CeO2.

关键词： Mn_2O_3 CeO_2 surface oxygen Oxidation activity Crystal structure