The influence of alkali metal cations in substituted nanostructured LaCoO<sub>3</sub> on oxidation catalytic activity
Yen Quach, Thi Hoang; Nguyet Tran, Thi Minh; Chi Tran, Que; Trung Nguyen, Quoc; Toan Nguyen, Thi; Khuong Le, Dang; Yen Quach, Thi Hoang; Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Vietnam; Nguyet Tran, Thi Minh; Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Vietnam; Chi Tran, Que; Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Vietnam; Trung Nguyen, Quoc; Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Vietnam; Toan Nguyen, Thi; Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Vietnam; Khuong Le, Dang; Hanoi National University of Education, 136 Xuan Thuy Street, Cau Giay District, Hanoi, Vietnam
Журнал:
Advances in Natural Sciences: Nanoscience and Nanotechnology
Дата:
2011-12-01
Аннотация:
Perovskite-type oxides La<sub>0.9</sub>M<sub>0.1</sub>CoO<sub>3</sub> (M=K/Na/Li) were prepared by a citrate sol–gel method. These oxides were characterized by x-ray diffraction analysis (XRD), a scanning electron microscope (SEM) and the N<sub>2</sub> physisorption Brunauer–Emmitt–Teller (BET) method. Their catalytic activity was studied by a constant microflow method for CO- and C<sub>3</sub>H<sub>6</sub>-oxidation and by thermal decomposition of diesel soot. The results show that the obtained perovskite materials have a sphere shape, particles size of about 40–50 nm and surface area from 12.0 to 14.9 m<sup>2</sup> g<sup>−1</sup>. They have high catalytic activities decreasing in the sequence K > Na > Li on conversion CO, C<sub>3</sub>H<sub>6</sub> and diesel soot. The total conversion temperature of CO, C<sub>3</sub>H<sub>6</sub> and diesel soot is 325 °C, 340 °C and 430 °C, respectively. Thus, these catalysts have high applicability in the removal of exhaust gas, especially from diesel engines.
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