Machida Shingo, Kato Reo, Hasegawa Kaishi, Gotoh Takahiro, Katsumata Ken-Ichi, Yasumori Atsuo
Department of Material Science and Technology, Faculty of Advanced Engineering, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan.
Material Characterization Central Laboratory, School of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan.
Materials (Basel). 2022 Jul 24;15(15):5132. doi: 10.3390/ma15155132.
Photoreduction of Cu ions to Cu metal by titanium(IV) oxide (TiO) 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 and 2 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/g for the silica-surfactant and TiO, respectively, to 591 m/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 was used solely. Therefore, this study indicated that the photoreduction of Cu ions to Cu metal by TiO 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. Thus, this study presents a new application of the conversion of a silica-surfactant hybrid into mesoporous silicas.
在硫酸条件下，于二氧化硅 - 表面活性剂杂化物存在的情况下，通过二氧化钛（TiO₂）将铜离子光还原为金属铜。辐照后，产物中出现深红色、X射线衍射图谱中因金属铜产生的反射以及X射线光电子能谱中因Cu²⁺和Cu⁺产生的峰，表明产物中有金属铜沉淀。此外，产物的布鲁诺尔 - 埃米特 - 泰勒比表面积从二氧化硅 - 表面活性剂和TiO₂分别为36和45 m²/g增加到591 m²/g，傅里叶变换红外光谱中C - H伸缩带强度降低，这意味着反应过程中表面活性剂被去除。单独使用TiO₂时从未观察到这些特征。因此，本研究表明在硫酸介质中，TiO₂促进了铜离子向金属铜的光还原，在酸性条件下从二氧化硅 - 表面活性剂杂化物中被质子提取的表面活性剂成功地被TiO₂光氧化。因此，本研究提出了二氧化硅 - 表面活性剂杂化物转化为介孔二氧化硅的新应用。
