The colloidal crystal template or opal with a closed-packed face centered cubic (fcc) lattice, was prepared from monodisperse polystyrene (PS) spheres by gravity sedimentation. The template was used for the generatio...The colloidal crystal template or opal with a closed-packed face centered cubic (fcc) lattice, was prepared from monodisperse polystyrene (PS) spheres by gravity sedimentation. The template was used for the generation of photonic crystal. The template provided void space for infiltration of liquid precursor composed of titanium butyloxide, barium acetate, ethanol, and acetic acid. The opal composite was hydrolyzed, dried, sintered by heating for completely removing PS spheres to form BaTiO3 photonic crystals with inverse opal structure. The PS spheres were replaced by air spheres, which interconnected each other through the windows on the BaTiO3 wall. So both the BaTiO3 wall and air void constitute continuous phases.展开更多
The colloidal crystal template or opal with a closed-packed face-centered cubic （fcc） lattice was prepared from monodisperse polystyrene （PS） spheres by vertical sedimentation. The template provided void space for...The colloidal crystal template or opal with a closed-packed face-centered cubic （fcc） lattice was prepared from monodisperse polystyrene （PS） spheres by vertical sedimentation. The template provided void space for infiltration of monomer precursor composed of acrylate acid, acrylamide and ammonium-persulfate, as well as microgel from the subsequent copolymerization. The sample was immersed in dimethylbenzene for completely removing PS spheres to form PAM inverse opal hydrogels （IOHPAM） or PAM/PAA inverse opal hydrogels （IOHPAM/PAA） photonic crystals. The PS spheres were replaced by air spheres, which interconnected each other through the windows. The study of responses to pH show that there are two peaks for both IOHPAM and IOHPAM/PAA films, but the IOHPAM/PAA peaks shift to higher pH, and the peaks are independent with the AA content.展开更多
We present the details of the sol-gel processing used to realize inverse silica opal,where the silica was activated with 0.3 mol% of Er3+ ions. The template(direct opal) was obtained assembling polystyrene spheres of ...We present the details of the sol-gel processing used to realize inverse silica opal,where the silica was activated with 0.3 mol% of Er3+ ions. The template(direct opal) was obtained assembling polystyrene spheres of the dimensions of 260 nm by means of a vertical deposition technique. The Er3+-activated silica inverse opal was obtained infiltrating,into the void of the template,the silica sol doped with Er3+ ions and subsequently removing the polystyrene spheres by means of calcinations. Scanning electron microscope showed that the inverse opals possess a fcc structure with a air hollows of about 210 nm and a photonic band gap,in the visible range,was observed from reflectance measurements. Spectroscopic properties of Er3+-activated silica inverse opal were investigated by luminescence spectroscopy,where,upon excitation at 514.5 nm,an emission of 4I13/2 → 4I15/2 of Er3+ ions transition with a 21 nm bandwidth was observed. Moreover the 4I13/2 level decay curve presents a single-exponential profile,with a measured lifetime of 18 ms,corresponding a high quantum efficiency of the system.展开更多
Thermodynamic stability, microvoid distribution and phases transformation of natural pozzolana opal shale（POS） were studied systematically in this work. XRD analysis showed that opal-CT, including microcrystal crist...Thermodynamic stability, microvoid distribution and phases transformation of natural pozzolana opal shale（POS） were studied systematically in this work. XRD analysis showed that opal-CT, including microcrystal cristobalite and tridymite, is a major component of POS. DTA and FT-IR indicated that there were many hydroxyl groups and acid sites on the surface of amorphous SiO2 materials. FE-SEM analysis exhibited amorphous SiO2 particles（opal-A） covering over stacking sequences microcrystal cristobalite and tridymite. Meanwhile, MIP analysis demonstrated that porosity and pore size distribution of POS remained uniform below 600 ℃. Because stable porous microstructure is a key factor in improving photocatalyst activity, POS is suited to preparing highly active supported.展开更多
With the advantages of better mimicking the specificity of natural tissues,three-dimensional(3D)cell culture plays a major role in drug development,toxicity testing,and tissue engineering.However,existing scaffolds or...With the advantages of better mimicking the specificity of natural tissues,three-dimensional(3D)cell culture plays a major role in drug development,toxicity testing,and tissue engineering.However,existing scaffolds or microcarriers for 3D cell culture are often limited in size and show suboptimal performance in simulating the vascular complexes of living organisms.Therefore,we present a novel hierarchically inverse opal porous scaffold made via a simple microfluidic approach for promoting 3D cell co-culture techniques.The designed scaffold is constructed using a combined concept involving an emulsion droplet template and inert polymer polymerization.This work demonstrates that the resultant scaffolds ensure a sufficient supply of nutrients during cell culture,so as to achieve large-volume cell culture.In addition,by serially planting different cells in the scaffold,a 3D co-culture system of endothelial-cellencapsulated hepatocytes can be developed for constructing certain functional tissues.It is also demonstrated that the use of the proposed scaffold for a co-culture system helps hepatocytes to maintain specific in vivo functions.These hierarchically inverse opal scaffolds lay the foundation for 3D cell culture and even the construction of biomimetic tissues.展开更多
A thermal-responsive photonic crystal material was fabricated by forming an inverse opal nanocomposite hydrogel of poly(N-isopropylacrylamide)(IONHPNIPAm)within the interstitial space of a polystyrene photonic crystal...A thermal-responsive photonic crystal material was fabricated by forming an inverse opal nanocomposite hydrogel of poly(N-isopropylacrylamide)(IONHPNIPAm)within the interstitial space of a polystyrene photonic crystal template.In IONHPNIPAm,PNIPAm were physically cross-linked with two kinds of nanoparticles(carbon dots and laponite clays).The integration of carbon dots and laponite clays for physical crosslinking endowed IONHPNIPAm sufficient strength and self-healing property.IONHPNIPAm films can be completely peeled from the substrates to be utilized as an independent photonic crystal material.The structural color and optical diffraction of the IONHPNIPAm exhibits a rapid reversible change in response to external thermal stimuli due to its physical cross-linking feature.Moreover,the IONHPNIPAm shows clear fluorescence due to the introduction of carbon dots,which enables a convenient way for chemical detection(such as the detection of silver ions).This stimuli-responsive photonic crystal materials based on physically cross-linked inverse opal nanocomposite hydrogels with fast response and good mechanical stability are promising for applications in the fields of smart optical detectors,thermal-responsive sensors and chemical detectors.展开更多
文摘The colloidal crystal template or opal with a closed-packed face centered cubic (fcc) lattice, was prepared from monodisperse polystyrene (PS) spheres by gravity sedimentation. The template was used for the generation of photonic crystal. The template provided void space for infiltration of liquid precursor composed of titanium butyloxide, barium acetate, ethanol, and acetic acid. The opal composite was hydrolyzed, dried, sintered by heating for completely removing PS spheres to form BaTiO3 photonic crystals with inverse opal structure. The PS spheres were replaced by air spheres, which interconnected each other through the windows on the BaTiO3 wall. So both the BaTiO3 wall and air void constitute continuous phases.
基金supported by the National Natural Science Foundation of China(No.50473044).
文摘The colloidal crystal template or opal with a closed-packed face-centered cubic （fcc） lattice was prepared from monodisperse polystyrene （PS） spheres by vertical sedimentation. The template provided void space for infiltration of monomer precursor composed of acrylate acid, acrylamide and ammonium-persulfate, as well as microgel from the subsequent copolymerization. The sample was immersed in dimethylbenzene for completely removing PS spheres to form PAM inverse opal hydrogels （IOHPAM） or PAM/PAA inverse opal hydrogels （IOHPAM/PAA） photonic crystals. The PS spheres were replaced by air spheres, which interconnected each other through the windows. The study of responses to pH show that there are two peaks for both IOHPAM and IOHPAM/PAA films, but the IOHPAM/PAA peaks shift to higher pH, and the peaks are independent with the AA content.
基金The work has been supported by the MIUR-FIRB RBNE012N3X,MIUR PRIN, PAT FAPVU 2004-2006,GRICES-CNR.
文摘We present the details of the sol-gel processing used to realize inverse silica opal,where the silica was activated with 0.3 mol% of Er3+ ions. The template(direct opal) was obtained assembling polystyrene spheres of the dimensions of 260 nm by means of a vertical deposition technique. The Er3+-activated silica inverse opal was obtained infiltrating,into the void of the template,the silica sol doped with Er3+ ions and subsequently removing the polystyrene spheres by means of calcinations. Scanning electron microscope showed that the inverse opals possess a fcc structure with a air hollows of about 210 nm and a photonic band gap,in the visible range,was observed from reflectance measurements. Spectroscopic properties of Er3+-activated silica inverse opal were investigated by luminescence spectroscopy,where,upon excitation at 514.5 nm,an emission of 4I13/2 → 4I15/2 of Er3+ ions transition with a 21 nm bandwidth was observed. Moreover the 4I13/2 level decay curve presents a single-exponential profile,with a measured lifetime of 18 ms,corresponding a high quantum efficiency of the system.
基金Funded by the National Natural Science Foundation of China(Nos.51278086,51578108)Special Fund for Scientific Research in the Public Interest by Ministry of Water Resource of the People’s Republic of China(No.201501003)
文摘Thermodynamic stability, microvoid distribution and phases transformation of natural pozzolana opal shale（POS） were studied systematically in this work. XRD analysis showed that opal-CT, including microcrystal cristobalite and tridymite, is a major component of POS. DTA and FT-IR indicated that there were many hydroxyl groups and acid sites on the surface of amorphous SiO2 materials. FE-SEM analysis exhibited amorphous SiO2 particles（opal-A） covering over stacking sequences microcrystal cristobalite and tridymite. Meanwhile, MIP analysis demonstrated that porosity and pore size distribution of POS remained uniform below 600 ℃. Because stable porous microstructure is a key factor in improving photocatalyst activity, POS is suited to preparing highly active supported.
基金the National Key Research and Development Program of China(2020YFA0908200)the National Natural Science Foundation of China(52073060,32101159,and 61927805)+1 种基金the Shenzhen Fundamental Research Program(JCYJ20190813152616459)the Wenzhou Institute,University of Chinese Academy of Sciences(WIUCAS)’startup fund(WIUCASQD2019007).
文摘With the advantages of better mimicking the specificity of natural tissues,three-dimensional(3D)cell culture plays a major role in drug development,toxicity testing,and tissue engineering.However,existing scaffolds or microcarriers for 3D cell culture are often limited in size and show suboptimal performance in simulating the vascular complexes of living organisms.Therefore,we present a novel hierarchically inverse opal porous scaffold made via a simple microfluidic approach for promoting 3D cell co-culture techniques.The designed scaffold is constructed using a combined concept involving an emulsion droplet template and inert polymer polymerization.This work demonstrates that the resultant scaffolds ensure a sufficient supply of nutrients during cell culture,so as to achieve large-volume cell culture.In addition,by serially planting different cells in the scaffold,a 3D co-culture system of endothelial-cellencapsulated hepatocytes can be developed for constructing certain functional tissues.It is also demonstrated that the use of the proposed scaffold for a co-culture system helps hepatocytes to maintain specific in vivo functions.These hierarchically inverse opal scaffolds lay the foundation for 3D cell culture and even the construction of biomimetic tissues.
基金Funded by the National Natural Science Foundation of China(No.51873167)the National Innovation and Entrepreneurship Training Program for College Students(No.S202010497024)。
文摘A thermal-responsive photonic crystal material was fabricated by forming an inverse opal nanocomposite hydrogel of poly(N-isopropylacrylamide)(IONHPNIPAm)within the interstitial space of a polystyrene photonic crystal template.In IONHPNIPAm,PNIPAm were physically cross-linked with two kinds of nanoparticles(carbon dots and laponite clays).The integration of carbon dots and laponite clays for physical crosslinking endowed IONHPNIPAm sufficient strength and self-healing property.IONHPNIPAm films can be completely peeled from the substrates to be utilized as an independent photonic crystal material.The structural color and optical diffraction of the IONHPNIPAm exhibits a rapid reversible change in response to external thermal stimuli due to its physical cross-linking feature.Moreover,the IONHPNIPAm shows clear fluorescence due to the introduction of carbon dots,which enables a convenient way for chemical detection(such as the detection of silver ions).This stimuli-responsive photonic crystal materials based on physically cross-linked inverse opal nanocomposite hydrogels with fast response and good mechanical stability are promising for applications in the fields of smart optical detectors,thermal-responsive sensors and chemical detectors.
