Tremendous research efforts have been aimed at ever-increasing worldwide energy demand. For this purpose, the hybrid supercapacitor power cell were prepared composing 3D porous graphene decorated with Co_3O_4-CeO_2 na...Tremendous research efforts have been aimed at ever-increasing worldwide energy demand. For this purpose, the hybrid supercapacitor power cell were prepared composing 3D porous graphene decorated with Co_3O_4-CeO_2 nano-particles herein by using flower stem as biotemplate. The resulting samples were characterized by field emission scanning electron microscopy(FESEM), transmission electron microscopy(TEM), Raman spectra, X-ray diffraction spectroscopy(XRD), nitrogen adsorption and desorption, X-ray photoelectron spectrogram(XPS), and electrochemical test. The 3D graphene acted as an excellent carrier together with Co_3O_4-CeO_2 nano-particles, boosting the specific capacitance of composite(221 F/g), which exceeded the theoretical value limit. This facile biotemplate method of research provided an eco-friendly and cut-price route to obtain high-quality graphene and Co_3O_4-CeO_2nano-composites owing to the unique porous structure derived from original template(flower stem). The finding presented a simple strategy for fabrication of novel energy storage devices.展开更多
Hydrophobic nano silver films were fabricated on butterfly wings as bio-template. The micrometric/nano structures and hydrophobicity of the surfaces were investigated with the help of scanning electron microscope(SEM...Hydrophobic nano silver films were fabricated on butterfly wings as bio-template. The micrometric/nano structures and hydrophobicity of the surfaces were investigated with the help of scanning electron microscope(SEM) and video-based contact angle meter. The hydrophobic mechanism of silver film was analyzed with the aid of Cas- sie's formula. On the nano silver films of various thicknesses(5, 10, 20, 40, 60, 80, 100 nm), all the contact an- gles(CAs) of water were bigger than 120°. When the silver film was 5 nm, the CAs of water on it on the wing surfa- ces of Mimathyma nycteis and Speyeria aglaja were 143.2° and 139.2°, respectively. Coated with the sliver film of the same thickness, butterfly wing surface exhibited the CA remarkably bigger than glass slide surface, exhibiting its high hydrophobicity. With the increase of silver film thickness on butterfly wing surface, the hydrophobicity kept de- creasing. The micrometric/nano hierarchical structures on butterfly wing surface result in the transition of metal silver from hydrophilicity to hydrophobicity.展开更多
In this paper,we used Corn Stalk(CS)as a renewable and economical bio template to fabricate willemite scaffolds with the potential application in skull bone repair.CS was used as a sacrificial template to synthesize t...In this paper,we used Corn Stalk(CS)as a renewable and economical bio template to fabricate willemite scaffolds with the potential application in skull bone repair.CS was used as a sacrificial template to synthesize the scaffolds.Willemite scaffolds with the chemical formula of Zn2SiO4 and pore size in the range of 3 to 10µm could be successfully synthesized by soaking CS in the willemite solution for 24 h and sintering at 950°C for 5 h.The porosity of the samples was controlled by the soaking time(between 12 and 48 h)in the willemite solution from 5 to 35%,respectively.The properties of these scaffolds showed a good approximation with cranial bone tissue.In addition,cytotoxicity assays(MTT)were performed on Human Bone Marrow Stromal cells(HBMSc)and A172 human glioblastoma cell lines by direct and indirect culture methods to estimate their toxicity for bone and nerve cells,respectively.Alkaline Phosphatase(ALP)activity and DAPI/Phalloidin cell staining were also performed to investigate the efficiency of the scaffolds for bone tissue engineering applications.The results showed that the scaffolds had good biocompatibility with both HBMSC and A172 cells,noticeable improvement on ALP activity,and great apatite formation ability in Simulated Body Fluid(SBF).All the evidence ascertained that willemite scaffolds made by corn stalks could be a useful candidate for bone tissue engineering applications.展开更多
Biomimetic nano CeO2 materials were prepared by using bean sprouts as bio-template through impregnation and thermal decomposition. For characterization of structure, X-ray diffraction spectroscopy (XRD), field emiss...Biomimetic nano CeO2 materials were prepared by using bean sprouts as bio-template through impregnation and thermal decomposition. For characterization of structure, X-ray diffraction spectroscopy (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectra (UV-Vis/DRS) nitrogen adsorp- tion-desorption measurements and Labsolar H2 system were adopted. The results demonstrated that the samples prepared at 550 ℃ not only completely removed the original bio-template, but also retained the morphology and microstructure of bean sprouts. Then the biomorphic structure of fluorite structure CeO2 material was obtained. Micro-pores with a diameter of about 2-3 nm were distributed among the particles, which provided more favorable channel for the photocatalytic reaction. Biomimetic CeO2 materials exhibited clear red shift (50 nm) compared with powder CeO2, which could be excited by visible irradiation. Biomimetic CeO2 materials dis- played the superior photocatalytic activity for the hydrogen production by water splitting under the sunlight irradiation, the hydrogen yield could reach 400 ktmol/g catalyst after 6 h.展开更多
CeO2 hollow microspheres were prepared through a facile method by using yeast cells as bio-templates. The yeast pro- vided a solid flame for the deposition of cerium hydroxide to form the hybrid Ce(OH)3@yeast precur...CeO2 hollow microspheres were prepared through a facile method by using yeast cells as bio-templates. The yeast pro- vided a solid flame for the deposition of cerium hydroxide to form the hybrid Ce(OH)3@yeast precursor. The resulting CeO2 hollow microspheres were obtained by calcining the precursor. The products were characterized by field emission scanning electron micros- copy (FE-SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), fourier transform infrared spectroscopy (FTIR), N2 adsorption/desorption analysis, X-ray photoelectron spectrum (XPS) and H2 temperature programmed reduction (H2-TPR) It was found that the products fully retained the morphology of the yeast cells and the size of the hollow microspheres was about 1.5-2 μm. The catalytic test results showed that the as-obtained hollow CeO2 microspheres possessed a higher catalytic activity in CO oxidation than the commercial CeO2, which attributed to their higher surface area, hollow structure and superior reducibility. This study provided a promising route for the preparation of a variety of other inorganic hollow microspheres.展开更多
基金supported by the National Natural Science Foundation of China(51478285,21407111)Natural Science Foundation of Jiangsu Province(BK20140280,BK20151198)+2 种基金Collegiate Natural Science Fund of Jiangsu Province(14KJA430004,16KJA430008)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Jiangsu Collaborative Innovation Center of Technology and Material for Water Treatment,Excellent Innovation Team in Science and Technology of Education Department of Jiangsu Province
文摘Tremendous research efforts have been aimed at ever-increasing worldwide energy demand. For this purpose, the hybrid supercapacitor power cell were prepared composing 3D porous graphene decorated with Co_3O_4-CeO_2 nano-particles herein by using flower stem as biotemplate. The resulting samples were characterized by field emission scanning electron microscopy(FESEM), transmission electron microscopy(TEM), Raman spectra, X-ray diffraction spectroscopy(XRD), nitrogen adsorption and desorption, X-ray photoelectron spectrogram(XPS), and electrochemical test. The 3D graphene acted as an excellent carrier together with Co_3O_4-CeO_2 nano-particles, boosting the specific capacitance of composite(221 F/g), which exceeded the theoretical value limit. This facile biotemplate method of research provided an eco-friendly and cut-price route to obtain high-quality graphene and Co_3O_4-CeO_2nano-composites owing to the unique porous structure derived from original template(flower stem). The finding presented a simple strategy for fabrication of novel energy storage devices.
基金Supported by the National Natural Science Foundation of China(Nos.50875108, 31370475), the Natural Science Foundation of Science and Technology Department of Jilin Province of China(No.201115162), the Science and Technology Project of De- partment of Education of Jilin Province of China(Nos.2009210, 2010373, 2011186) and the Open Fund of Key Laboratory of Bionic Engineering of Ministry of Education of China(No.K201004).
文摘Hydrophobic nano silver films were fabricated on butterfly wings as bio-template. The micrometric/nano structures and hydrophobicity of the surfaces were investigated with the help of scanning electron microscope(SEM) and video-based contact angle meter. The hydrophobic mechanism of silver film was analyzed with the aid of Cas- sie's formula. On the nano silver films of various thicknesses(5, 10, 20, 40, 60, 80, 100 nm), all the contact an- gles(CAs) of water were bigger than 120°. When the silver film was 5 nm, the CAs of water on it on the wing surfa- ces of Mimathyma nycteis and Speyeria aglaja were 143.2° and 139.2°, respectively. Coated with the sliver film of the same thickness, butterfly wing surface exhibited the CA remarkably bigger than glass slide surface, exhibiting its high hydrophobicity. With the increase of silver film thickness on butterfly wing surface, the hydrophobicity kept de- creasing. The micrometric/nano hierarchical structures on butterfly wing surface result in the transition of metal silver from hydrophilicity to hydrophobicity.
文摘In this paper,we used Corn Stalk(CS)as a renewable and economical bio template to fabricate willemite scaffolds with the potential application in skull bone repair.CS was used as a sacrificial template to synthesize the scaffolds.Willemite scaffolds with the chemical formula of Zn2SiO4 and pore size in the range of 3 to 10µm could be successfully synthesized by soaking CS in the willemite solution for 24 h and sintering at 950°C for 5 h.The porosity of the samples was controlled by the soaking time(between 12 and 48 h)in the willemite solution from 5 to 35%,respectively.The properties of these scaffolds showed a good approximation with cranial bone tissue.In addition,cytotoxicity assays(MTT)were performed on Human Bone Marrow Stromal cells(HBMSc)and A172 human glioblastoma cell lines by direct and indirect culture methods to estimate their toxicity for bone and nerve cells,respectively.Alkaline Phosphatase(ALP)activity and DAPI/Phalloidin cell staining were also performed to investigate the efficiency of the scaffolds for bone tissue engineering applications.The results showed that the scaffolds had good biocompatibility with both HBMSC and A172 cells,noticeable improvement on ALP activity,and great apatite formation ability in Simulated Body Fluid(SBF).All the evidence ascertained that willemite scaffolds made by corn stalks could be a useful candidate for bone tissue engineering applications.
基金Project supported by the National Natural Science Foundation of China(21277094,51478285,21407111)Natural Science Foundation of Jiangsu Province(BK2012167,BK20140280)+5 种基金Collegiate Natural Science Fund of Jiangsu Province(14KJA430004,12KJA430005)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Applied Basic Research Project of Suzhou(SYG201316)Jiangsu Key Laboratory for Environment Functional Materials(SJHG1304,SJHG1310)Creative Project of Postgraduate of Jiangsu Province(CXZZ13_0855)Excellent Innovation Team in Science and Technology of University in Jiangsu Province and Collabrative Innovation Center of Technology and Material of Water Treatment
文摘Biomimetic nano CeO2 materials were prepared by using bean sprouts as bio-template through impregnation and thermal decomposition. For characterization of structure, X-ray diffraction spectroscopy (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectra (UV-Vis/DRS) nitrogen adsorp- tion-desorption measurements and Labsolar H2 system were adopted. The results demonstrated that the samples prepared at 550 ℃ not only completely removed the original bio-template, but also retained the morphology and microstructure of bean sprouts. Then the biomorphic structure of fluorite structure CeO2 material was obtained. Micro-pores with a diameter of about 2-3 nm were distributed among the particles, which provided more favorable channel for the photocatalytic reaction. Biomimetic CeO2 materials exhibited clear red shift (50 nm) compared with powder CeO2, which could be excited by visible irradiation. Biomimetic CeO2 materials dis- played the superior photocatalytic activity for the hydrogen production by water splitting under the sunlight irradiation, the hydrogen yield could reach 400 ktmol/g catalyst after 6 h.
基金supported by the National Natural Science Foundation of China(21476071)Shanghai Leading Academic Discipline Project(B502)the Shanghai Engineering Research Center of Space Engine(13DZ2250600)
文摘CeO2 hollow microspheres were prepared through a facile method by using yeast cells as bio-templates. The yeast pro- vided a solid flame for the deposition of cerium hydroxide to form the hybrid Ce(OH)3@yeast precursor. The resulting CeO2 hollow microspheres were obtained by calcining the precursor. The products were characterized by field emission scanning electron micros- copy (FE-SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), fourier transform infrared spectroscopy (FTIR), N2 adsorption/desorption analysis, X-ray photoelectron spectrum (XPS) and H2 temperature programmed reduction (H2-TPR) It was found that the products fully retained the morphology of the yeast cells and the size of the hollow microspheres was about 1.5-2 μm. The catalytic test results showed that the as-obtained hollow CeO2 microspheres possessed a higher catalytic activity in CO oxidation than the commercial CeO2, which attributed to their higher surface area, hollow structure and superior reducibility. This study provided a promising route for the preparation of a variety of other inorganic hollow microspheres.