This work aimed to use oyster shell powder (OSP) as the partial replacement of Ag/TiO2 particle to obtain multifunctional β-hemihydrate gypsum.Thus,the β-hemihydrate gypsum was mixed with different contents of OSP a...This work aimed to use oyster shell powder (OSP) as the partial replacement of Ag/TiO2 particle to obtain multifunctional β-hemihydrate gypsum.Thus,the β-hemihydrate gypsum was mixed with different contents of OSP and Ag/TiO2 particle.Antibacterial and MB removal experiments were conducted to assess the antibacterial characteristic and photocatalytic activity of β-hemihydrate gypsum with Ag/TiO2 particle and OSP.Besides,the formaldehyde degradation test was carried out to evaluate its formaldehyde removal ratio.Moreover,their setting times,compressive and flexural strengths at 1,3,and 28 days were comparatively analyzed.The experimental results prove that the composite use of OSP and Ag/TiO2 particle provide feasible multifunction for the β-hemihydrate gypsum.They can further improve the bactericidal rates and exhibit extra MB removal ratios compared with the gypsum plasters with single Ag/TiO2 particle.Besides,they can increase the formaldehyde degradation ratios,and this promotion is related to the introduction of Ag/TiO2 particle.However,OSP delays the initial setting time but promotes the final setting time of β-hemihydrate gypsum,and Ag/TiO2 particle hardly affects the setting times.Furthermore,OSP reduces the strengths of plasters at 1,3,and 28 days.But in general,the composite addition of OSP and Ag/TiO2 particle increase the compressive and flexural strengths of gypsum plasters at 1,3,and 28 days.These results provide theoretical guidance for the recycling of OSP and the preparation of gypsum-based products with antibacterial and formaldehyde degradation capabilities.展开更多
Optical properties of obliquely deposited TiO2/Ag/TiO2 multilayered films prepared by thermal evaporation and sputtering methods were investigated for energy efficiency of architectural and automobile windows. Investi...Optical properties of obliquely deposited TiO2/Ag/TiO2 multilayered films prepared by thermal evaporation and sputtering methods were investigated for energy efficiency of architectural and automobile windows. Investigation on the influency of layer thickness on the properties of TiO2/Ag/TiO2 films yield an optimum layer thickness of 5 nm/14 nm/5 nm and 10 nm/14 nm/10 nm for optimal solar control performance of TiO2/Ag/TiO2 films deposited by sputtering and thermal evaporation methods. The optimum films were then obliquely deposited with deposition angle varying from 0° to 70° for the purpose of optimizing angular selectivity of the films. The spectral transmittances were measured by HITACHI model U-2000 double beam UV-VIS-Spectrophotometer. The optimum thickness provided a peak transmittance of 70% at a wavelength of 400 nm for near normal thermally evaporated thin films, and 72% for films deposited by sputtering unit at - 320 ℃ for TiO2 layers. Influence of deposition angle for obliquely deposited thin films was investigated for both sputtered and thermal evaporated thin films. The transmittance values for the films deposited by both methods gradually increased with increasing deposition angles to a peak of 80% at 400 nm wavelength. The angular transmittance measurements were taken for the optimum films with 10 rim/14 rim/10 nm thicknesses due to relatively larger overall film thickness as compared to 5 nm/14 nm/5 nm. Films deposited at 30°, 40°and 60°, with incident light angle of± 10°, ± 30°, ± 50° and ± 70°were used for transmittance measurements. Best angular performance of 7% was realized at ± 10° light incidence angle for films prepared at 60° deposition angle.展开更多
采用溶胶-凝胶浸渍提拉法在石英玻璃片上制备了Ag/TiO2薄膜。为研究不同热处理温度(500,600,700℃)对制备过程的影响,在薄膜的制备过程中其他的条件均不变(钛酸丁酯和硝酸银的摩尔比为1:0.18)。用透射电子显微镜(Transmission Electron ...采用溶胶-凝胶浸渍提拉法在石英玻璃片上制备了Ag/TiO2薄膜。为研究不同热处理温度(500,600,700℃)对制备过程的影响,在薄膜的制备过程中其他的条件均不变(钛酸丁酯和硝酸银的摩尔比为1:0.18)。用透射电子显微镜(Transmission Electron Microscope,TEM)记录样品的透射显微镜图像和衍射花样以表征薄膜的结构,用背散射电子(Backscattered Electron,BSE)检测器观察样品表面的组分分布,用能谱EDAX(Energy Dispersive Analysis of X-rays)分析Ag/TiO2薄膜样品的元素成分组成。实验结果表明,500℃热处理时得到了含有尺寸均匀的纳米银粒子的Ag/TiO2膜,随着热处理温度的升高,Ag的颗粒逐渐长大,尺寸分布变得不均匀,同时,膜中的银逐渐向薄膜表面迁移并挥发。展开更多
TiO2 nanotubes were prepared under normal pressure at a temperature of 120 ℃. Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were prepared by m icrowave assisted heating polyol process. TEM images showed that m...TiO2 nanotubes were prepared under normal pressure at a temperature of 120 ℃. Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were prepared by m icrowave assisted heating polyol process. TEM images showed that microwave prepa red Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were small and well dis persed on the surface of the TiO2 nanotubes. UV-Vis absorption spectra showed th at the absorbance of Ag/TiO2 nanotubes and Au/TiO2 nanotubes in the visible ligh t range increased greatly compared to the single titania nanotubes.展开更多
基金Funded by the National Natural Science Foundation of China(51878479)。
摘要This work aimed to use oyster shell powder (OSP) as the partial replacement of Ag/TiO2 particle to obtain multifunctional β-hemihydrate gypsum.Thus,the β-hemihydrate gypsum was mixed with different contents of OSP and Ag/TiO2 particle.Antibacterial and MB removal experiments were conducted to assess the antibacterial characteristic and photocatalytic activity of β-hemihydrate gypsum with Ag/TiO2 particle and OSP.Besides,the formaldehyde degradation test was carried out to evaluate its formaldehyde removal ratio.Moreover,their setting times,compressive and flexural strengths at 1,3,and 28 days were comparatively analyzed.The experimental results prove that the composite use of OSP and Ag/TiO2 particle provide feasible multifunction for the β-hemihydrate gypsum.They can further improve the bactericidal rates and exhibit extra MB removal ratios compared with the gypsum plasters with single Ag/TiO2 particle.Besides,they can increase the formaldehyde degradation ratios,and this promotion is related to the introduction of Ag/TiO2 particle.However,OSP delays the initial setting time but promotes the final setting time of β-hemihydrate gypsum,and Ag/TiO2 particle hardly affects the setting times.Furthermore,OSP reduces the strengths of plasters at 1,3,and 28 days.But in general,the composite addition of OSP and Ag/TiO2 particle increase the compressive and flexural strengths of gypsum plasters at 1,3,and 28 days.These results provide theoretical guidance for the recycling of OSP and the preparation of gypsum-based products with antibacterial and formaldehyde degradation capabilities.
摘要Optical properties of obliquely deposited TiO2/Ag/TiO2 multilayered films prepared by thermal evaporation and sputtering methods were investigated for energy efficiency of architectural and automobile windows. Investigation on the influency of layer thickness on the properties of TiO2/Ag/TiO2 films yield an optimum layer thickness of 5 nm/14 nm/5 nm and 10 nm/14 nm/10 nm for optimal solar control performance of TiO2/Ag/TiO2 films deposited by sputtering and thermal evaporation methods. The optimum films were then obliquely deposited with deposition angle varying from 0° to 70° for the purpose of optimizing angular selectivity of the films. The spectral transmittances were measured by HITACHI model U-2000 double beam UV-VIS-Spectrophotometer. The optimum thickness provided a peak transmittance of 70% at a wavelength of 400 nm for near normal thermally evaporated thin films, and 72% for films deposited by sputtering unit at - 320 ℃ for TiO2 layers. Influence of deposition angle for obliquely deposited thin films was investigated for both sputtered and thermal evaporated thin films. The transmittance values for the films deposited by both methods gradually increased with increasing deposition angles to a peak of 80% at 400 nm wavelength. The angular transmittance measurements were taken for the optimum films with 10 rim/14 rim/10 nm thicknesses due to relatively larger overall film thickness as compared to 5 nm/14 nm/5 nm. Films deposited at 30°, 40°and 60°, with incident light angle of± 10°, ± 30°, ± 50° and ± 70°were used for transmittance measurements. Best angular performance of 7% was realized at ± 10° light incidence angle for films prepared at 60° deposition angle.
摘要采用溶胶-凝胶浸渍提拉法在石英玻璃片上制备了Ag/TiO2薄膜。为研究不同热处理温度(500,600,700℃)对制备过程的影响,在薄膜的制备过程中其他的条件均不变(钛酸丁酯和硝酸银的摩尔比为1:0.18)。用透射电子显微镜(Transmission Electron Microscope,TEM)记录样品的透射显微镜图像和衍射花样以表征薄膜的结构,用背散射电子(Backscattered Electron,BSE)检测器观察样品表面的组分分布,用能谱EDAX(Energy Dispersive Analysis of X-rays)分析Ag/TiO2薄膜样品的元素成分组成。实验结果表明,500℃热处理时得到了含有尺寸均匀的纳米银粒子的Ag/TiO2膜,随着热处理温度的升高,Ag的颗粒逐渐长大,尺寸分布变得不均匀,同时,膜中的银逐渐向薄膜表面迁移并挥发。
摘要TiO2 nanotubes were prepared under normal pressure at a temperature of 120 ℃. Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were prepared by m icrowave assisted heating polyol process. TEM images showed that microwave prepa red Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were small and well dis persed on the surface of the TiO2 nanotubes. UV-Vis absorption spectra showed th at the absorbance of Ag/TiO2 nanotubes and Au/TiO2 nanotubes in the visible ligh t range increased greatly compared to the single titania nanotubes.