Photoreduction of Copper Ions Using Silica–Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid Conditions
Photoreduction of Cu<sup>2+</sup> ions to Cu metal by titanium(IV) oxide (TiO<sub>2</sub>) was conducted in the presence of a silica–surfactant hybrid under sulfuric acid conditions. After irradiation, a dark-red color, reflections due to Cu metal in the X-ray diffraction pat...
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2022-07-01
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| author | Shingo Machida Reo Kato Kaishi Hasegawa Takahiro Gotoh Ken-ichi Katsumata Atsuo Yasumori |
| author_facet | Shingo Machida Reo Kato Kaishi Hasegawa Takahiro Gotoh Ken-ichi Katsumata Atsuo Yasumori |
| author_sort | Shingo Machida |
| collection | DOAJ |
| description | Photoreduction of Cu<sup>2+</sup> ions to Cu metal by titanium(IV) oxide (TiO<sub>2</sub>) was conducted in the presence of a silica–surfactant hybrid under sulfuric acid conditions. After irradiation, a dark-red color, reflections due to Cu metal in the X-ray diffraction pattern, and peaks due to Cu 2<i>p</i><sub>1/2</sub> and 2<i>p</i><sub>3/2</sub> in the X-ray photoelectron spectrum indicated the precipitation of Cu metal in the product. In addition, an increase in the Brunauer–Emmett–Teller specific surface area from 36 and 45 m<sup>2</sup>/g for the silica–surfactant and TiO<sub>2</sub>, respectively, to 591 m<sup>2</sup>/g for the product, and a decrease in the intensity of the C-H stretching band in the Fourier–transform infra-red spectra implied the removal of surfactant during the reaction. These characteristics were never observed when TiO<sub>2</sub> was used solely. Therefore, this study indicated that the photoreduction of Cu<sup>2+</sup> ions to Cu metal by TiO<sub>2</sub> was facilitated under the sulfuric acid medium, where the surfactants extracted from silica–surfactant hybrids by protons in the acidic condition were successfully photo-oxidized by TiO<sub>2</sub>. Thus, this study presents a new application of the conversion of a silica–surfactant hybrid into mesoporous silicas. |
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| issn | 1996-1944 |
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| last_indexed | 2024-03-09T12:25:32Z |
| publishDate | 2022-07-01 |
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| series | Materials |
| spelling | doaj.art-2f23a4f672e64328a2718b927707be872023-11-30T22:34:58ZengMDPI AGMaterials1996-19442022-07-011515513210.3390/ma15155132Photoreduction of Copper Ions Using Silica–Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid ConditionsShingo Machida0Reo Kato1Kaishi Hasegawa2Takahiro Gotoh3Ken-ichi Katsumata4Atsuo Yasumori5Department of Material Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, JapanDepartment of Material Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, JapanDepartment of Material Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, JapanMaterial Characterization Central Laboratory, School of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, JapanDepartment of Material Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, JapanDepartment of Material Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, JapanPhotoreduction of Cu<sup>2+</sup> ions to Cu metal by titanium(IV) oxide (TiO<sub>2</sub>) was conducted in the presence of a silica–surfactant hybrid under sulfuric acid conditions. After irradiation, a dark-red color, reflections due to Cu metal in the X-ray diffraction pattern, and peaks due to Cu 2<i>p</i><sub>1/2</sub> and 2<i>p</i><sub>3/2</sub> in the X-ray photoelectron spectrum indicated the precipitation of Cu metal in the product. In addition, an increase in the Brunauer–Emmett–Teller specific surface area from 36 and 45 m<sup>2</sup>/g for the silica–surfactant and TiO<sub>2</sub>, respectively, to 591 m<sup>2</sup>/g for the product, and a decrease in the intensity of the C-H stretching band in the Fourier–transform infra-red spectra implied the removal of surfactant during the reaction. These characteristics were never observed when TiO<sub>2</sub> was used solely. Therefore, this study indicated that the photoreduction of Cu<sup>2+</sup> ions to Cu metal by TiO<sub>2</sub> was facilitated under the sulfuric acid medium, where the surfactants extracted from silica–surfactant hybrids by protons in the acidic condition were successfully photo-oxidized by TiO<sub>2</sub>. Thus, this study presents a new application of the conversion of a silica–surfactant hybrid into mesoporous silicas.https://www.mdpi.com/1996-1944/15/15/5132mesoporous silicasilica–surfactant hybridheavy metal ionphotoreductiontitanium oxide |
| spellingShingle | Shingo Machida Reo Kato Kaishi Hasegawa Takahiro Gotoh Ken-ichi Katsumata Atsuo Yasumori Photoreduction of Copper Ions Using Silica–Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid Conditions Materials mesoporous silica silica–surfactant hybrid heavy metal ion photoreduction titanium oxide |
| title | Photoreduction of Copper Ions Using Silica–Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid Conditions |
| title_full | Photoreduction of Copper Ions Using Silica–Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid Conditions |
| title_fullStr | Photoreduction of Copper Ions Using Silica–Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid Conditions |
| title_full_unstemmed | Photoreduction of Copper Ions Using Silica–Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid Conditions |
| title_short | Photoreduction of Copper Ions Using Silica–Surfactant Hybrid and Titanium (IV) Oxide under Sulfuric Acid Conditions |
| title_sort | photoreduction of copper ions using silica surfactant hybrid and titanium iv oxide under sulfuric acid conditions |
| topic | mesoporous silica silica–surfactant hybrid heavy metal ion photoreduction titanium oxide |
| url | https://www.mdpi.com/1996-1944/15/15/5132 |
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