Abstract
Synthetic nickelian malachite nanopowders (Cu1-xNix)2(OH)2CO3 with x = 0, 0.02, 0.04, 0.06, 0.08, and 0.1 were prepared by constant-pH coprecipitation. N2 sorption isotherms confirmed a steady increase of the BET surface area with increasing Ni content for the as-synthesized and calcined mesoporous materials. Powder XRD patterns for x ≤ 0.1 indicate the formation of single-phase materials with an anisotropic contraction of the unit cell. This is related to the gradual decrease of the Jahn-Teller distortion in the malachite structure. An XRD-amorphous hydroxide-rich phase is formed for x > 0.1, which appears as spongelike regions in SEM images. Thermogravimetric analysis showed that nickel lowers the onset of thermal decomposition. Powder XRD patterns of the calcined samples evidence the formation of a tenorite structure despite the presence of Ni. Heterogeneous Fenton-like decomposition of Bismarck Brown Y with H2O2 showed that a Cu/Ni ratio of 92:8 in the nanostructured oxide leads to the highest reaction rate constant derived from a pseudo-first-order kinetic rate law expression. Temperature-programmed CO oxidation experiments revealed that pure CuO achieved the highest activity. Similar performance was observed for the binary system obtained through calcination of the precursor prepared with a Cu/Ni ratio of 96:4.
Original language | English |
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Pages (from-to) | 2063-2071 |
Number of pages | 9 |
Journal | European Journal of Inorganic Chemistry |
Volume | 2016 |
Issue number | 13-14 |
DOIs | |
Publication status | Published - 1 May 2016 |
Externally published | Yes |
Keywords
- Copper
- Coprecipitation
- Heterogeneous catalysis
- Nanostructures
- Nickel
- Oxidation