Egg-shaped core/shell α-Mn2O3@α-MnO2 as heterogeneous catalysts for decomposition of phenolics in aqueous solutions
Novel uniform ellipsoid a-Mn2O3@a-MnO2 core/shell (McMs) nanocomposites were prepared via a hydrothermal process with a shape-control protocol followed by calcination at different temperatures. The properties of the composites were characterized by a number of techniques such as thermogravimetric an...
| Main Authors: | , , , , |
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| Format: | Journal Article |
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Elsevier
2016
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| Online Access: | http://hdl.handle.net/20.500.11937/4952 |
| _version_ | 1848744659213352960 |
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| author | Saputra, E. Zhang, H. Liu, Q. Sun, Hongqi Wang, S. |
| author_facet | Saputra, E. Zhang, H. Liu, Q. Sun, Hongqi Wang, S. |
| author_sort | Saputra, E. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Novel uniform ellipsoid a-Mn2O3@a-MnO2 core/shell (McMs) nanocomposites were prepared via a hydrothermal process with a shape-control protocol followed by calcination at different temperatures. The properties of the composites were characterized by a number of techniques such as thermogravimetric analysis (TGA), X-ray diffraction (XRD), N2 adsorption, and scanning electron microscopy (SEM). The core/shell materials were much effective in heterogeneous oxone® activation to generate sulfate and hydroxyl radicals for degradation of aqueous phenol. The McMs composites demonstrated catalytic activity for 100% phenol decomposition in short duration varying between 20 and 120 min, much higher than that of homogeneous Mn2+ system with 95% phenol degradation in 120 min. They also showed a higher activity than single-phase a-Mn2O3 or a-MnO2. The catalytic activity of phenol degradation depends on temperature, oxone® concentration, phenol concentration, and catalyst loading. The catalysts also showed a stable activity in several cycles. Kinetic study demonstrated that phenol degradation reactions follow a first order reaction on McMs catalysts giving activation energies at 32.1–68.8 kJ/mol. With the detection of radicals by electron paramagnetic resonance (EPR), the generation mechanism was proposed. |
| first_indexed | 2025-11-14T06:04:59Z |
| format | Journal Article |
| id | curtin-20.500.11937-4952 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T06:04:59Z |
| publishDate | 2016 |
| publisher | Elsevier |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-49522017-09-13T14:47:33Z Egg-shaped core/shell α-Mn2O3@α-MnO2 as heterogeneous catalysts for decomposition of phenolics in aqueous solutions Saputra, E. Zhang, H. Liu, Q. Sun, Hongqi Wang, S. Novel uniform ellipsoid a-Mn2O3@a-MnO2 core/shell (McMs) nanocomposites were prepared via a hydrothermal process with a shape-control protocol followed by calcination at different temperatures. The properties of the composites were characterized by a number of techniques such as thermogravimetric analysis (TGA), X-ray diffraction (XRD), N2 adsorption, and scanning electron microscopy (SEM). The core/shell materials were much effective in heterogeneous oxone® activation to generate sulfate and hydroxyl radicals for degradation of aqueous phenol. The McMs composites demonstrated catalytic activity for 100% phenol decomposition in short duration varying between 20 and 120 min, much higher than that of homogeneous Mn2+ system with 95% phenol degradation in 120 min. They also showed a higher activity than single-phase a-Mn2O3 or a-MnO2. The catalytic activity of phenol degradation depends on temperature, oxone® concentration, phenol concentration, and catalyst loading. The catalysts also showed a stable activity in several cycles. Kinetic study demonstrated that phenol degradation reactions follow a first order reaction on McMs catalysts giving activation energies at 32.1–68.8 kJ/mol. With the detection of radicals by electron paramagnetic resonance (EPR), the generation mechanism was proposed. 2016 Journal Article http://hdl.handle.net/20.500.11937/4952 10.1016/j.chemosphere.2016.06.021 Elsevier restricted |
| spellingShingle | Saputra, E. Zhang, H. Liu, Q. Sun, Hongqi Wang, S. Egg-shaped core/shell α-Mn2O3@α-MnO2 as heterogeneous catalysts for decomposition of phenolics in aqueous solutions |
| title | Egg-shaped core/shell α-Mn2O3@α-MnO2 as heterogeneous catalysts for decomposition of phenolics in aqueous solutions |
| title_full | Egg-shaped core/shell α-Mn2O3@α-MnO2 as heterogeneous catalysts for decomposition of phenolics in aqueous solutions |
| title_fullStr | Egg-shaped core/shell α-Mn2O3@α-MnO2 as heterogeneous catalysts for decomposition of phenolics in aqueous solutions |
| title_full_unstemmed | Egg-shaped core/shell α-Mn2O3@α-MnO2 as heterogeneous catalysts for decomposition of phenolics in aqueous solutions |
| title_short | Egg-shaped core/shell α-Mn2O3@α-MnO2 as heterogeneous catalysts for decomposition of phenolics in aqueous solutions |
| title_sort | egg-shaped core/shell α-mn2o3@α-mno2 as heterogeneous catalysts for decomposition of phenolics in aqueous solutions |
| url | http://hdl.handle.net/20.500.11937/4952 |