Hollow @CuMgAl double layered hydrotalcites and mixed oxides with tunable textural and structural properties, and thus enhanced NH₃-NO_<i>x</i>-SCR activity

Journal article

Well-organized, spherical, mesoporous hollow @CuMgAl-LDHs (layered double hydroxides) are prepared by the controlled removal of the SiO2 from SiO2@CuMgAl-LDH core-shell hybrids that in turn are synthesized via a bottom-up strategy. The materials are prepared with various Cu/Mg molar ratios (Cu/Mg = 0.05-0.50) while keeping the ratio of Cu and Mg constant, (Cu + Mg)/Al = 2. The effect of Cu doping and the silica core removal process (conducted for 4 h at 30 degrees C using 1 M NaOH) on the chemical composition, morphology, structure, texture and reducibility of the resulting materials are described. @CuMgAl-MOs (mixed oxides) obtained by thermal treatment of the @CuMgAl-LDHs are active and selective catalysts for the selective catalytic reduction of NOx using ammonia, and effectively operate at low temperatures. The N-2 yield increases with increased Cu content in the CuMgAl shell, which is associated with the easier reducibility of the Cu species incorporated into the MgAl matrix. @CuMgAl-MOs show better catalytic performance than bulk CuMgAl MOs.Dobře organizované, sférické, mezoporézní duté @CuMgAl-LDH (vrstvené podvojné hydroxidy) byly připraveny řízeným odstraňováním Si02 z hybridů Si02@CuMgAl-LDH. Materiály bylůy připraveny s různými molárními poměry Cu/Mg (Cu/Mg = 0,05-0,50) při zachování konstantního poměru (Cu+Mg)/Al = 2. Studie popisuje účinek dopování mědí a odstranění jádra oxidu křemičitého na chemické složení, morfologii, strukturu, texturu a redukovatelnost výsledných materiálů

Authors: Kondratowicz, T; Horký, O; Slang, S; Dubnová, L; Gajewska, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Royal Society of Chemistry
• Journal: Nanoscale Advances
• Volume: 5
• Issue: 11
• Pages: 3063-3074
• Publication date: 2023-05-30
• DOI: 10.1039/d3na00125c
• EISSN: 2516-0230
• ISSN: 2516-0230
• Language: English
• Keywords: Double layered; Composite material; Crystallography; Hydrotalcite; Catalysis; Chemistry; Layered double hydroxides; Chemical engineering; Organic chemistry; Materials science