Numerical simulation has been performed on the optical transmission enhancement properties of a one-dimensional Ag film single slit structure with grooves. The results show that the position,depth and number of the gr...Numerical simulation has been performed on the optical transmission enhancement properties of a one-dimensional Ag film single slit structure with grooves. The results show that the position,depth and number of the grooves have great influence on the optical transmission,and surface plasmon polariton and resonance mode are the primary factors. The maximal extinction ratio of 35.8 dB is achieved in the single slit structure by adjusting groove depth.展开更多
Nano sized powders of TiO2 (titanium dioxide) and Nb2O5 (Niobium (V) oxide) were used to fabricate TiO2/Nb2O5 composites thin films by EPD (electrophoretic deposition) technique. The metal oxide powders, toget...Nano sized powders of TiO2 (titanium dioxide) and Nb2O5 (Niobium (V) oxide) were used to fabricate TiO2/Nb2O5 composites thin films by EPD (electrophoretic deposition) technique. The metal oxide powders, together with magnesium nitrate hexahydrate pellets, were suspended in propan-2-ol inside an EPD cell. The electrodes, placed 1.2 cm apart, were partially immersed in the suspension and a DC potential applied across them. Key EPD process parameters, which include applied DC electric field, deposition time and solid concentration in suspension, were optimized through visual inspection and from UV-Vis-NIR spectrophotometer spectra. The highest (55%) transmittance was obtained for films with deposition time of 90 s, powder concentration of 0.01 g/40 mL, and 35 V DC (direct current) voltage. XRD micrographs confirmed that TiO2 and Nb2O5 particles were presented in the composite film. SEM (scanning electron microscope) micrographs of the composite electrode thin films showed that porous films of high quality with well controlled morphology were deposited by using the EPD technique.展开更多
A novel multi-tube photoreactor with 0.0188m3 valid reaction volume was constructed in pilot-scale. This rectangular reactor consisted of 13 regularly distributed silica glass tubes coating with TiO2 thin film photo-c...A novel multi-tube photoreactor with 0.0188m3 valid reaction volume was constructed in pilot-scale. This rectangular reactor consisted of 13 regularly distributed silica glass tubes coating with TiO2 thin film photo-catalyst. Total active area of TiO2 thin film is 0.3916m2. The ratio of surface area to volume achieves 20.8m-1. Photocatalytic experiment of phenol red demonstrates that the apparent reaction rate constant (k) is 0.074 65 h-1 and 0.16502h-1 for reaction system with and without micro-bubbles mixing. The corresponding apparent quantum efficiency (a) is 8.1771 X 10-7g.J-1 and 4.9036 x 10-7g-J-1, respectively. COD value of reactant could decrease to 17mg.L-1 and high performance liquid chromatography (HPLC) only shows two absorption peaks in 24 h pho-tocatalytic process time, so this photoreactor has good photomineralization effect. Experimental results reveal that photocatalytic destruction of organics is possible by using the multi-tube photoreactor.展开更多
In the present work,hierarchical nanostructured titanium dioxide(TiO2) films were fabricated on Ti-25Nb-3Mo-2Sn-3Zr(TLM) alloy for biomedical applications via one-step anodization process in ethylene glycolbased elect...In the present work,hierarchical nanostructured titanium dioxide(TiO2) films were fabricated on Ti-25Nb-3Mo-2Sn-3Zr(TLM) alloy for biomedical applications via one-step anodization process in ethylene glycolbased electrolyte containing 0.5wt% NH4F.The nanostructured TiO2 films exhibited three distinct types depending on the anodization time:top irregular nanopores(INP)/beneath regular nanopores(RNP),top INP/middle regular nanotubes(RNT)/bottom RNP and top RNT with underlying RNP.The evolution of the nanostructured TiO2 films with anodization time demonstrated that self-organizing nanopores formed at the very beginning and individual nanotubes originated from underlying nanopore dissolution.Furthermore,a modified two-stage self-organizing mechanism was introduced to illustrate the growth of the nanostructured TiO2 films.Compared with TLM titanium alloy matrix,the TiO2 films with special nano-structure hold better hydrophilicity and higher specific surface area,which lays the foundation for their biomedical applications.展开更多
The laser equipment is one of the key equipment in the production line of the solar energy. In this article, the author de-scribes the application of the laser equipment in the production line of the amorphous silicon...The laser equipment is one of the key equipment in the production line of the solar energy. In this article, the author de-scribes the application of the laser equipment in the production line of the amorphous silicon film solar cells, and points out that the stable and exactitude is the key direction of the future development of the laser scribing equipment.展开更多
据phys.org网11月15日消息,韩国蔚山科学技术院(Ulsan National Institute of Science and Technology,UNIST)的研究人员开发出一种用于辐射防护的MXene-碳化硼复合中子屏蔽膜,该屏蔽膜厚度仅为数十微米,可有效阻挡辐射中的中子。研究...据phys.org网11月15日消息,韩国蔚山科学技术院(Ulsan National Institute of Science and Technology,UNIST)的研究人员开发出一种用于辐射防护的MXene-碳化硼复合中子屏蔽膜,该屏蔽膜厚度仅为数十微米,可有效阻挡辐射中的中子。研究人员直接合成了二维纳米材料MXene和母体MAX相,将碳化硼通过超声处理和离心分离分成能够吸收中子的小颗粒并均匀分散在溶液中,通过控制MXene和碳化硼的性能提高混合溶液的稳定性,制备出一种大面积、柔性、轻质、结构致密的薄膜,再通过涂漆技术将薄膜应用于不同的表面。展开更多
Structural manipulation of graphene oxide (GO) building blocks has been widely researched. Concerning GO membranes for separation applications, the validity and maintenance of their microscopic structures in the chemi...Structural manipulation of graphene oxide (GO) building blocks has been widely researched. Concerning GO membranes for separation applications, the validity and maintenance of their microscopic structures in the chemical environment are pivotal for effective separation at the molecular scale. Cationic interactions with both aromatic rings and oxygenated functional groups of GO make metal ions intriguing for physically and chemically structural reinforcement. By filtrating GO suspension through the substrate loaded with cations, stacking o f GO nanosheets and diffusion of cations steadily evolve simultaneously in an aqueous environment without flocculation. Thus, thin and homogeneous GO membrane is obtained. Divalent and monovalent cations were studied regarding their interactions with GO, and the performance of correspondingly functionalized membranes was evaluated. The divalent cation-stabilized membranes have favorable stability in the separation of water/ethanol. This facile fabrication and functionalization method may also be applicable for structure construction of other two-dimensional materials.展开更多
Transferring MoS2 films from growth substrates onto target substrates is a critical issue for their practical applications. Moreover, it remains a great challenge to avoid sample degradation and substrate destruction,...Transferring MoS2 films from growth substrates onto target substrates is a critical issue for their practical applications. Moreover, it remains a great challenge to avoid sample degradation and substrate destruction, because the current transfer method inevitably employs a wet chemical etching process. We developed an etching-free transfer method for transferring MoS2 films onto arbitrary substrates by using ultrasonication. Briefly, the collapse of ultrasonication-generated microbubbles at the interface between polymer-coated MoS2 film and substrates induce sufficient force to delaminate the MoS2 films. Using this method, the MoS2 films can be transferred from all substrates (silica, mica, strontium titanate, and sapphire) and retains the original sample morphology and quality. This method guarantees a simple transfer process and allows the reuse of growth substrates, without involving any hazardous etchants. The etching-free transfer method is likely to promote broad applications of MoS2 in photodetectors.展开更多
Electrochromism refers to the persistent and reversible change of optical properties by an applied voltage pulse.Electrochromic(EC)devices have been extensively studied because of their commercial applications in smar...Electrochromism refers to the persistent and reversible change of optical properties by an applied voltage pulse.Electrochromic(EC)devices have been extensively studied because of their commercial applications in smart windows of green buildings,display devices and thermal control of equipments.In this review,a basic EC device design is presented based on useful oxides and solid-state electrolytes.We focus on the state-of-the-art research activities related to the structures of tungsten oxide(WO_3)and nickel oxide(NiO),summarizing the strategies to improve their EC performances and further applications of devices.展开更多
Titanium dioxide (TiO2) thin films were grown onto Indium tin oxide (ITO) glass under atmospheric pressure by chemical va- por deposition (AP-MOCVD) using titanium tetraisopropoxide astitanium precursor. The as-...Titanium dioxide (TiO2) thin films were grown onto Indium tin oxide (ITO) glass under atmospheric pressure by chemical va- por deposition (AP-MOCVD) using titanium tetraisopropoxide astitanium precursor. The as-prepared TiOe/ITO films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and photoelectrochemical measurements. Their photocatalytic (PC) and photoelec- trocatalytic (PEC) activities were evaluated based on the results of methyl orange dye (MO) degradation experiments in aque- ous solution. The difference between the front side (EE, electrolyte/electrode interface) and the back side (SE, sub- strate/electrode interface) illumination was evaluated in both photocurrent and MO degradation experiments. The effect of the film thickness on degradation rate by PEC under the two illumination directions was also studied. Stability of TiO2/ITO film electrode was investigated in repetitive degradation experiments. Overall, the TiO2/ITO film with thickness ranging from 321 to1440 nm deposited by MOCVD method is an effective photoelectrode for MO degradation under SE illumination in PEC reaction system.展开更多
The utilization of Na2S/Na2SO3 mixture as the electrolyte solution to stabilize sulfide anode in a photoelectrochemical cell for hydrogen evolution generally compromises the current-to-hydrogen efficiency(ηcurrent)...The utilization of Na2S/Na2SO3 mixture as the electrolyte solution to stabilize sulfide anode in a photoelectrochemical cell for hydrogen evolution generally compromises the current-to-hydrogen efficiency(ηcurrent) of the system. Here, the employment of a dual-electrolyte system,that is, Na2S/Na2SO3 mixture and p H-neutral Na2SO4 as the respective electrolyte solutions in the anode and cathode chambers of a water splitting cell is demonstrated to suppress the photocorrosion of CuInS2-In2O3-TiO2 nanotube(CISIn2O3-TNT) heterostructure, while simultaneously boosts theηcurrent. Although n-type CIS and In2O3 nanoparticles can be easily formed on TNT array via facile pulse-assisted electrodeposition method, conformal deposition of the nanoparticles homogeneously on the nanotubes wall with preservation of the TNT hollow structure is shown to be essential for achieving efficient charge generation and separation within the heterostructure. In comparison to Na2S/Na2SO3 solution as the sole electrolyte in both the anode and cathode chambers, introduction of dual electrolyte is shown to not only enhance the photostability of the CIS-In2O3-TNT anode, but also lead to near-unity ηcurrentas opposed to the merely 20% ηcurrentof the single-electrolyte system.展开更多
基金the Key Program of National Natural Science of China(Grant No.50734007)the Research Foundation from Ministry of Education of China (Grant No.208133)the Natural Science Foundation of Yunnan Province (Grant No.2007F005M)
文摘Numerical simulation has been performed on the optical transmission enhancement properties of a one-dimensional Ag film single slit structure with grooves. The results show that the position,depth and number of the grooves have great influence on the optical transmission,and surface plasmon polariton and resonance mode are the primary factors. The maximal extinction ratio of 35.8 dB is achieved in the single slit structure by adjusting groove depth.
文摘Nano sized powders of TiO2 (titanium dioxide) and Nb2O5 (Niobium (V) oxide) were used to fabricate TiO2/Nb2O5 composites thin films by EPD (electrophoretic deposition) technique. The metal oxide powders, together with magnesium nitrate hexahydrate pellets, were suspended in propan-2-ol inside an EPD cell. The electrodes, placed 1.2 cm apart, were partially immersed in the suspension and a DC potential applied across them. Key EPD process parameters, which include applied DC electric field, deposition time and solid concentration in suspension, were optimized through visual inspection and from UV-Vis-NIR spectrophotometer spectra. The highest (55%) transmittance was obtained for films with deposition time of 90 s, powder concentration of 0.01 g/40 mL, and 35 V DC (direct current) voltage. XRD micrographs confirmed that TiO2 and Nb2O5 particles were presented in the composite film. SEM (scanning electron microscope) micrographs of the composite electrode thin films showed that porous films of high quality with well controlled morphology were deposited by using the EPD technique.
基金Supported by the Natural Science Foundation of Jiangsu Province (JH01-010).
文摘A novel multi-tube photoreactor with 0.0188m3 valid reaction volume was constructed in pilot-scale. This rectangular reactor consisted of 13 regularly distributed silica glass tubes coating with TiO2 thin film photo-catalyst. Total active area of TiO2 thin film is 0.3916m2. The ratio of surface area to volume achieves 20.8m-1. Photocatalytic experiment of phenol red demonstrates that the apparent reaction rate constant (k) is 0.074 65 h-1 and 0.16502h-1 for reaction system with and without micro-bubbles mixing. The corresponding apparent quantum efficiency (a) is 8.1771 X 10-7g.J-1 and 4.9036 x 10-7g-J-1, respectively. COD value of reactant could decrease to 17mg.L-1 and high performance liquid chromatography (HPLC) only shows two absorption peaks in 24 h pho-tocatalytic process time, so this photoreactor has good photomineralization effect. Experimental results reveal that photocatalytic destruction of organics is possible by using the multi-tube photoreactor.
基金Supported by the National Natural Science Foundation of China(No.51372169)Natural Science Foundation of Tianjin(No.11JCZDJC17300)
文摘In the present work,hierarchical nanostructured titanium dioxide(TiO2) films were fabricated on Ti-25Nb-3Mo-2Sn-3Zr(TLM) alloy for biomedical applications via one-step anodization process in ethylene glycolbased electrolyte containing 0.5wt% NH4F.The nanostructured TiO2 films exhibited three distinct types depending on the anodization time:top irregular nanopores(INP)/beneath regular nanopores(RNP),top INP/middle regular nanotubes(RNT)/bottom RNP and top RNT with underlying RNP.The evolution of the nanostructured TiO2 films with anodization time demonstrated that self-organizing nanopores formed at the very beginning and individual nanotubes originated from underlying nanopore dissolution.Furthermore,a modified two-stage self-organizing mechanism was introduced to illustrate the growth of the nanostructured TiO2 films.Compared with TLM titanium alloy matrix,the TiO2 films with special nano-structure hold better hydrophilicity and higher specific surface area,which lays the foundation for their biomedical applications.
文摘The laser equipment is one of the key equipment in the production line of the solar energy. In this article, the author de-scribes the application of the laser equipment in the production line of the amorphous silicon film solar cells, and points out that the stable and exactitude is the key direction of the future development of the laser scribing equipment.
文摘据phys.org网11月15日消息,韩国蔚山科学技术院(Ulsan National Institute of Science and Technology,UNIST)的研究人员开发出一种用于辐射防护的MXene-碳化硼复合中子屏蔽膜,该屏蔽膜厚度仅为数十微米,可有效阻挡辐射中的中子。研究人员直接合成了二维纳米材料MXene和母体MAX相,将碳化硼通过超声处理和离心分离分成能够吸收中子的小颗粒并均匀分散在溶液中,通过控制MXene和碳化硼的性能提高混合溶液的稳定性,制备出一种大面积、柔性、轻质、结构致密的薄膜,再通过涂漆技术将薄膜应用于不同的表面。
基金financially supported by the National Natural Science Foundation of China (21476107, 21490585, 21776125 and 51861135203)the Innovative Research Team Program by the Ministry of Education of China (IRT17R54)the Topnotch Academic Programs Project of Jiangsu Higher Education Institutions (TAPP)
文摘Structural manipulation of graphene oxide (GO) building blocks has been widely researched. Concerning GO membranes for separation applications, the validity and maintenance of their microscopic structures in the chemical environment are pivotal for effective separation at the molecular scale. Cationic interactions with both aromatic rings and oxygenated functional groups of GO make metal ions intriguing for physically and chemically structural reinforcement. By filtrating GO suspension through the substrate loaded with cations, stacking o f GO nanosheets and diffusion of cations steadily evolve simultaneously in an aqueous environment without flocculation. Thus, thin and homogeneous GO membrane is obtained. Divalent and monovalent cations were studied regarding their interactions with GO, and the performance of correspondingly functionalized membranes was evaluated. The divalent cation-stabilized membranes have favorable stability in the separation of water/ethanol. This facile fabrication and functionalization method may also be applicable for structure construction of other two-dimensional materials.
基金Acknowledgements This work was financially supported by the National Natural Science Foundation of China (Nos. 51222201, 51290272, 51472008, and 51432002), the National Basic Research Program of China (Nos. 2012CB921404, 2013CB932603, 2012CB933404, and 2011CB921903), and the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (No. 51121091).
文摘Transferring MoS2 films from growth substrates onto target substrates is a critical issue for their practical applications. Moreover, it remains a great challenge to avoid sample degradation and substrate destruction, because the current transfer method inevitably employs a wet chemical etching process. We developed an etching-free transfer method for transferring MoS2 films onto arbitrary substrates by using ultrasonication. Briefly, the collapse of ultrasonication-generated microbubbles at the interface between polymer-coated MoS2 film and substrates induce sufficient force to delaminate the MoS2 films. Using this method, the MoS2 films can be transferred from all substrates (silica, mica, strontium titanate, and sapphire) and retains the original sample morphology and quality. This method guarantees a simple transfer process and allows the reuse of growth substrates, without involving any hazardous etchants. The etching-free transfer method is likely to promote broad applications of MoS2 in photodetectors.
基金Program for Innovative Research Team in University of Ministry of Education of China (IRT13037)
文摘Electrochromism refers to the persistent and reversible change of optical properties by an applied voltage pulse.Electrochromic(EC)devices have been extensively studied because of their commercial applications in smart windows of green buildings,display devices and thermal control of equipments.In this review,a basic EC device design is presented based on useful oxides and solid-state electrolytes.We focus on the state-of-the-art research activities related to the structures of tungsten oxide(WO_3)and nickel oxide(NiO),summarizing the strategies to improve their EC performances and further applications of devices.
基金financial support to this study by the National Natural Science Foundation of China (21076188, 20836008, 20976158, 20990221and 21076189)the Key Innovation Team for Science and Technology of Zhejiang Province of China (2009R50047)
文摘Titanium dioxide (TiO2) thin films were grown onto Indium tin oxide (ITO) glass under atmospheric pressure by chemical va- por deposition (AP-MOCVD) using titanium tetraisopropoxide astitanium precursor. The as-prepared TiOe/ITO films were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and photoelectrochemical measurements. Their photocatalytic (PC) and photoelec- trocatalytic (PEC) activities were evaluated based on the results of methyl orange dye (MO) degradation experiments in aque- ous solution. The difference between the front side (EE, electrolyte/electrode interface) and the back side (SE, sub- strate/electrode interface) illumination was evaluated in both photocurrent and MO degradation experiments. The effect of the film thickness on degradation rate by PEC under the two illumination directions was also studied. Stability of TiO2/ITO film electrode was investigated in repetitive degradation experiments. Overall, the TiO2/ITO film with thickness ranging from 321 to1440 nm deposited by MOCVD method is an effective photoelectrode for MO degradation under SE illumination in PEC reaction system.
基金supported by the Australian Research Council (DP170102895)
文摘The utilization of Na2S/Na2SO3 mixture as the electrolyte solution to stabilize sulfide anode in a photoelectrochemical cell for hydrogen evolution generally compromises the current-to-hydrogen efficiency(ηcurrent) of the system. Here, the employment of a dual-electrolyte system,that is, Na2S/Na2SO3 mixture and p H-neutral Na2SO4 as the respective electrolyte solutions in the anode and cathode chambers of a water splitting cell is demonstrated to suppress the photocorrosion of CuInS2-In2O3-TiO2 nanotube(CISIn2O3-TNT) heterostructure, while simultaneously boosts theηcurrent. Although n-type CIS and In2O3 nanoparticles can be easily formed on TNT array via facile pulse-assisted electrodeposition method, conformal deposition of the nanoparticles homogeneously on the nanotubes wall with preservation of the TNT hollow structure is shown to be essential for achieving efficient charge generation and separation within the heterostructure. In comparison to Na2S/Na2SO3 solution as the sole electrolyte in both the anode and cathode chambers, introduction of dual electrolyte is shown to not only enhance the photostability of the CIS-In2O3-TNT anode, but also lead to near-unity ηcurrentas opposed to the merely 20% ηcurrentof the single-electrolyte system.