substitutes tion, high loosely dis Neodymium doped-yttrium aluminum garnet (Nd : YAG) transparent polycrystalline ceramics already become of single crystals because they are provided with easy fabrication, low cost...substitutes tion, high loosely dis Neodymium doped-yttrium aluminum garnet (Nd : YAG) transparent polycrystalline ceramics already become of single crystals because they are provided with easy fabrication, low cost, large size, highly doped concentraheat conductivity, mass fabrication, multi-layers and multi-filnctions. The Nd:YAG precursor powders with persed , slightly agglomerated, super fine and YAG cubic crystal phase were synthesized at 1100 ℃ by the homogeneous precipitation method, using Nd2O3, Y2O3, Al(NO3)3·9H2O and urea as raw materials, (NH4)2SO4 as electrical stabilizer, TEOS as sintering additive. The Nd:YAG transparent ceramics were prepared after being vacuum sintered at 1700 ℃ for 5 h. The Nd:YAG ceramic materials were characterized by the TG-DTA, XRD, FT-IR, TEM, FEG-ESEM and FT-PL. The results show that the crystallization temperature of YAG is 850 ℃ and the intermediate crystal phase YAP forming during the heat treatment transforms to YAG cubic crystal phase at 1050 ℃. The lasing wavelength of (Nd0.01 Y0.99)3Al5O12 transparent ceramics is 1.065 μm and there exists a slight red-shift compared to the single crystal with the same chemical composition. The optical transmittance is 45 % in the visible light and 58 % in the near infrared light and the optical transmittance descends with the decreasing the wavelength.展开更多
The rapid development of internet and internet of things brings new opportunities for the expansion of intelligent sensors,and acetone as a major disease detection indicator(i.e.,diabetes)making it become extremely im...The rapid development of internet and internet of things brings new opportunities for the expansion of intelligent sensors,and acetone as a major disease detection indicator(i.e.,diabetes)making it become extremely important clinical indicator.Herein,uniform mesoporous ZnO spheres were successfully synthesized via novel formaldehyde-assisted metal-ligand crosslinking strategy.In order to adjust the pore structure of mesoporous ZnO,various mesoporous ZnO spheres were synthesized by changing weight percentage of Zn(NO_(3))_(2)·6 H_(2)O to tannic acid(TA).Moreover,highly active heterojunction mesoporous ZnO/Co_(3)O_(4)has been fabricated based on as-prepared ultra-small Co_(3)O_(4)nanocrystals(ca.3 nm)and mesoporous ZnO spheres by flexible impregnation technique.Profit from nano-size effect and synergistic effect of p-n heterojunction,mesoporous ZnO/Co_(3)O_(4)exhibited excellent acetone sensing performance with high selectivity,superior sensitivity and responsiveness.Typically,5 wt%Co_(3)O_(4)embedded mesoporous ZnO sphere showed prominent acetone response(ca.46 for 50 ppm),which was about 11.5 times higher than that in pure ZnO sensing device,and it was also endowed high cyclic stability.The nanocrystals embedded hybrid material is expected to be used as promising efficient material in the field of catalysis and gas sensing.展开更多
Past decades have witnessed the explosive growth of interest in the field of bioinspired materials,of which the structures and properties can be well utilized for industrial and bioengineering applications.Among these...Past decades have witnessed the explosive growth of interest in the field of bioinspired materials,of which the structures and properties can be well utilized for industrial and bioengineering applications.Among these structures,the natural fibrous structures propose diverse strategies to adapt to their environment,offering inspirations for versatile applications,especially droplet manipulation.With various well-adapted soft structures and materials,these fibrous structures show good control over their interaction with liquids(e.g.,water),providing a database full of effective solutions to these droplet-related scientific and technical problems(e.g.,colloidal synthesis,single-cell gene sequencing,drug delivery and solution synthesis).In this review,the current achievements in water collection by multiple fibrous structures are highlighted;the structures,basic models,bio-inspired structures and their applications are presented;and the current challenges and future prospects for the development of bio-inspired fibrous structures are discussed.展开更多
文摘substitutes tion, high loosely dis Neodymium doped-yttrium aluminum garnet (Nd : YAG) transparent polycrystalline ceramics already become of single crystals because they are provided with easy fabrication, low cost, large size, highly doped concentraheat conductivity, mass fabrication, multi-layers and multi-filnctions. The Nd:YAG precursor powders with persed , slightly agglomerated, super fine and YAG cubic crystal phase were synthesized at 1100 ℃ by the homogeneous precipitation method, using Nd2O3, Y2O3, Al(NO3)3·9H2O and urea as raw materials, (NH4)2SO4 as electrical stabilizer, TEOS as sintering additive. The Nd:YAG transparent ceramics were prepared after being vacuum sintered at 1700 ℃ for 5 h. The Nd:YAG ceramic materials were characterized by the TG-DTA, XRD, FT-IR, TEM, FEG-ESEM and FT-PL. The results show that the crystallization temperature of YAG is 850 ℃ and the intermediate crystal phase YAP forming during the heat treatment transforms to YAG cubic crystal phase at 1050 ℃. The lasing wavelength of (Nd0.01 Y0.99)3Al5O12 transparent ceramics is 1.065 μm and there exists a slight red-shift compared to the single crystal with the same chemical composition. The optical transmittance is 45 % in the visible light and 58 % in the near infrared light and the optical transmittance descends with the decreasing the wavelength.
基金financially supported by the National Natural Science Foundation of China(Nos.21673048,21875044,52073064,22005058 and 22005057)National Key R&D Program of China(No.2018YFA0209401)+3 种基金Key Basic Research Program of Science and Technology Commission of Shanghai Municipality(No.20JC1415300)Program of Shanghai Academic Research Leader(No.19XD1420300)the state key laboratory of Transducer Technology of China(No.SKT1904)supporting project number(No.RSP-2020/155)。
文摘The rapid development of internet and internet of things brings new opportunities for the expansion of intelligent sensors,and acetone as a major disease detection indicator(i.e.,diabetes)making it become extremely important clinical indicator.Herein,uniform mesoporous ZnO spheres were successfully synthesized via novel formaldehyde-assisted metal-ligand crosslinking strategy.In order to adjust the pore structure of mesoporous ZnO,various mesoporous ZnO spheres were synthesized by changing weight percentage of Zn(NO_(3))_(2)·6 H_(2)O to tannic acid(TA).Moreover,highly active heterojunction mesoporous ZnO/Co_(3)O_(4)has been fabricated based on as-prepared ultra-small Co_(3)O_(4)nanocrystals(ca.3 nm)and mesoporous ZnO spheres by flexible impregnation technique.Profit from nano-size effect and synergistic effect of p-n heterojunction,mesoporous ZnO/Co_(3)O_(4)exhibited excellent acetone sensing performance with high selectivity,superior sensitivity and responsiveness.Typically,5 wt%Co_(3)O_(4)embedded mesoporous ZnO sphere showed prominent acetone response(ca.46 for 50 ppm),which was about 11.5 times higher than that in pure ZnO sensing device,and it was also endowed high cyclic stability.The nanocrystals embedded hybrid material is expected to be used as promising efficient material in the field of catalysis and gas sensing.
基金This work was financially supported by the National Natural Science Foundation of China(11532009,11522219).
文摘Past decades have witnessed the explosive growth of interest in the field of bioinspired materials,of which the structures and properties can be well utilized for industrial and bioengineering applications.Among these structures,the natural fibrous structures propose diverse strategies to adapt to their environment,offering inspirations for versatile applications,especially droplet manipulation.With various well-adapted soft structures and materials,these fibrous structures show good control over their interaction with liquids(e.g.,water),providing a database full of effective solutions to these droplet-related scientific and technical problems(e.g.,colloidal synthesis,single-cell gene sequencing,drug delivery and solution synthesis).In this review,the current achievements in water collection by multiple fibrous structures are highlighted;the structures,basic models,bio-inspired structures and their applications are presented;and the current challenges and future prospects for the development of bio-inspired fibrous structures are discussed.