The sonocatalytic damage of bovine serum albumin （BSA） was studied in the presence of nanometer titanium dioxide （TiO2） powders by low frequency （80 kHz） ultrasound. The destruction of secondary structure and ch...The sonocatalytic damage of bovine serum albumin （BSA） was studied in the presence of nanometer titanium dioxide （TiO2） powders by low frequency （80 kHz） ultrasound. The destruction of secondary structure and change of α-helical structure of BSA were reflected by ultraviolet （UV） and circular dichroism （CD） spectroscopies.展开更多
In this work we have developed an analytical method to measure potential titanium debris released from TiO2 nanotube layers devices immersed in biological fluids. This quantitative study is highly required to ensure b...In this work we have developed an analytical method to measure potential titanium debris released from TiO2 nanotube layers devices immersed in biological fluids. This quantitative study is highly required to ensure both the security and non toxicity of the nanostructured surfaces used as future implantable medical devices in the living. A one-pot synthesis process is developed to produce high quality standard solutions of titanium dioxide nanoparticles in aqueous medium. The elaborated dispersion is then used to fabricate standard solutions in both aqueous and human blood plasma media. The synthesized nanoparticles dispersion was characterized by granulometry. The nanoparticles structure and morphology were then observed using Transmission Electron Microscopy (TEM). Thermogravimetric Analysis (TGA) was used to evaluate the concentration of TiO2 in the suspension. A quantitative routine by the use of Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) is developed. The quantification threshold of titanium species is found to be in the 30 - 40 ppb range. None interference is detected between the particles and the human blood plasma. Using the established quantitative routine, the titanium species release from titania nanotube layers in human blood plasma is evaluated.展开更多
A new type of inorganic-polymer materials of epoxy Titanium Dioxide and Zinc Oxide was prepared. In this work, the mechanical properties of polymer composites reinforced with ceramic nanoparticles were investigated. T...A new type of inorganic-polymer materials of epoxy Titanium Dioxide and Zinc Oxide was prepared. In this work, the mechanical properties of polymer composites reinforced with ceramic nanoparticles were investigated. Three points bending tests demonstrated an enhancement in flexural strength and flexural modulus respectively, compared to the pure epoxy. The reinforcement of nanoparticulate materials was Titanium Dioxide and Zinc Oxide with various weight fraction. Experimental tests results indicated that the composite materials have significantly higher modulus of elasticity than the matrix material. It was found that the enhancement in modulus of elasticity was directly proportional to the weight fraction of reinforcement material, and that Zinc Oxide composites have higher modulus of elasticity than Titanium Dioxide composites with equivalent of weight fraction. The wear results showed that nanoparticles improved the wear resistance of epoxy nanocomposites, the Titanium Dioxide matrix particles could improve the wear resistance of the epoxy more efficiently than Zinc Oxide particles. The fatigue test showed that the fatigue resistance of epoxy Zinc Oxide matrix particles was higher than that of Titanium Dioxide matrix particles.展开更多
The Dye Sensitized Solar Cell (DSSC) plays an important role because of low material cost, ease of production and high conversion efficiency as compared to other thin-film solar cell technologies. The main objective i...The Dye Sensitized Solar Cell (DSSC) plays an important role because of low material cost, ease of production and high conversion efficiency as compared to other thin-film solar cell technologies. The main objective is to create and find the best configuration of the solar cell based on materials that are inexpensive and highly efficient in solar energy conversion and subsequently test the efficiency of dye sensitized titanium dioxide solar cell. We begin the process with two glass plates coated with Fluorine tin oxide (FTO). Titanium dioxide is applied to the conductive side of one plate and the other plate is coated with graphite. A dye is adsorbed on to the TiO2 layer and then the plates are sandwiched together. A drop of iodide electrolyte is then added between the plates. The tests carried out indoors under a lamp emitting all wavelengths in the visible spectrum were not found to provide consistent data due to substantial heating of the cell. The outdoor tests carried out in natural sunlight exhibited steady voltage at much higher level. Future research will involve the incorporation of quantum dots instead of the organic dye as a sensitizer. Quantum dots have the advantages of providing tunable band gaps and the ability to absorb specific wavelength.展开更多
In the present work, composites of poly (methyl methacrylate)/titanium oxide nanoparticles (100/0, 97.5/2.5, 95/5, 92.5/7.5, 90/10 and 0/100 wt/wt%)were prepared to be used as bioequivalent materials according to thei...In the present work, composites of poly (methyl methacrylate)/titanium oxide nanoparticles (100/0, 97.5/2.5, 95/5, 92.5/7.5, 90/10 and 0/100 wt/wt%)were prepared to be used as bioequivalent materials according to their importance broad practical and medical applications. Thermal properties as well as X-ray diffraction analyses were employed to characterize the structure properties of such composite. The obtained results showed variations in the glass transition temperature (Tg), the melting temperature (Tm), shape and area of thermal peaks which were attributed to the different degrees of crystallinity and the existence of interactions between PMMA and TiO2 nanoparticle molecules. The XRD patterns showed sharpening of peaks at different concentrations of nano-TiO2 powder with PMMA. This indicated changes in the crystallinity/amorphosity ratio, and also suggested that the miscibility between the amorphous components of homo- polymers PMMA and nano-TiO2 powder is possible.The results showed that nano-TiO2 powder mix with PMMA can improve the thermal stability of the homo-polymer under investigation, lead- ing to interesting technological applications.展开更多
Titanium is a very important element for several industrial applications, being one of the ninth most abundant elements in the Earth’s crust (0.63% wt). In this work it will discuss the different mining and industria...Titanium is a very important element for several industrial applications, being one of the ninth most abundant elements in the Earth’s crust (0.63% wt). In this work it will discuss the different mining and industrial activities involved in the production of titanium dioxide. The first step analyzed will treat about the beneficiation mining process of titanium mineral, and secondly, it will discuss the two main processes of the TiO2 manufacturing (sulphate and chloride routes). In addition, we will show different uses of the titanium dioxide pigment as filler in paper, plastics and rubber industries and as flux in glass manufacture, etc. Finally, we will show that the old wastes are currently called co-products since they were valorized, being commercialized by the Spanish industry of TiO2 production in different fields such as agriculture, civil engineering, or cement manufacturing.展开更多
Junctions are an important structure that allows charge separation in solar cells and photocatalysts. Here, we studied the charge transfer at an anatase/rutile TiO2 phase junction using time-resolved photoluminescence...Junctions are an important structure that allows charge separation in solar cells and photocatalysts. Here, we studied the charge transfer at an anatase/rutile TiO2 phase junction using time-resolved photoluminescence spectroscopy. Visible （-S00 nm） and near-infrared （NIR, -830 nm） emissions were monitored to give insight into the photoinduced charges of anatase and rutile in the junction, respectively, New fast photoluminescence decay components appeared in the visible emission of futile-phase dominated TiO2 and in the NIR emission of many mixed phase TiO2samples. The fast decays confirmed that the charge separation occurred at the phase junction. The visible emission intensity from the mixed phase TiO2 increased, revealing that charge transfer from rutile to anatase was the main pathway. The charge separation slowed the microsecond time scale photolumines- cence decay rate for charge carriers in both anatase and rutile. However, the millisecond decay of the charge carriers in anatase TiO2 was accelerated, while there was almost no change in the charge carrier dynamics of rutile TiO2. Thus, charge separation at the anatase/rutile phase junction caused an increase in the charge carrier concentration on a microsecond time scale, because of slower electron-hole recombination. The enhanced photocatalytic activity previously observed at ana- tase/rutile phase junctions is likely caused by the improved charge carrier dynamics we report here. These findings may contribute to the development of improved photocatalytic materials.展开更多
Corrosion protection has become an important issue as the amount of infrastructure construction in marine environment increased.Photocathodic protection is a promising method to reduce the corrosion of metals,and tita...Corrosion protection has become an important issue as the amount of infrastructure construction in marine environment increased.Photocathodic protection is a promising method to reduce the corrosion of metals,and titanium dioxide(TiO2) is the most widely used photoanode.This review summarizes the progress in TiO2 photo gene rated protection in recent years.Different types of semiconductors,including sulfides,metals,metal oxide s,polymers,and other materials,are used to design and modify TiO2.The strategy to dramatically improve the efficiency of photoactivity is proposed,and the mechanism is investigated in detail.Characterization methods are also introduced,including morphology testing,light absorption,photoelectrochemistry,and protected metal observation.This review aims to provide a comprehensive overview of Ti02 development and guide photocathodic protection.展开更多
Hydrogen(H2)production from photocatalytic reforming of cellulose is a promising way for sustainable H2 to be generated.Herein,we report a systematic study of the photocatalytic reforming of cellulose over Pt/m-TiO2(i...Hydrogen(H2)production from photocatalytic reforming of cellulose is a promising way for sustainable H2 to be generated.Herein,we report a systematic study of the photocatalytic reforming of cellulose over Pt/m-TiO2(i.e.mixed TiO2,80%of anatase and 20%of rutile)catalysts in water.The optimum operation condition was established by studying the effect of Pt loading,catalyst concentration,cellulose concentration and reaction temperature on the gas production rate of H2(r(H2))and CO2(r(CO2)),suggesting an optimum operation condition at 40°C with 1.0 g·L^-1of cellulose and 0.75 g·L^-1of 0.16-Pt/m-TiO2 catalyst(with 0.16 wt%Pt loadting)to achieve a relatively sound photocatalytic performance with rH2=9.95μmol·h^-1.It is also shown that although the photoreforming of cellulose was operated at a relatively mild condition(i.e.with an UV-A lamp irradiation at40°C in the aqueous system),a low loading of Pt at^0.16 wt%on m-TiO2 could promote the H2 production effectively.Additionally,by comparing the reaction order expressed from both r(H2)(a1)and r(CO2)(a2)with respect to cellulose and water,the possible mechanism of H2 production was proposed.展开更多
A type of TiO/bamboo charcoal composite made by a dip-dry method was loaded onto wood veneer with a vacuum- pressure method in order to prepare modified poplar veneer. The pore structure parameters and surface morphol...A type of TiO/bamboo charcoal composite made by a dip-dry method was loaded onto wood veneer with a vacuum- pressure method in order to prepare modified poplar veneer. The pore structure parameters and surface morphology of the TiO2/ bamboo charcoal composite were determined and analyzed by means of a porosimetry analyzer and SEM. The results show that the surface morphology of the composite does not change after being loaded with nano TiO2. However, its specific surface area （359.814 m^2·g^-1）, pore volume （0.317 cm^3.g^-1） and average pore diameter （3.526 nm） increased; particularly the cumulative volume of pores was increased by 65.83%. In addition, the distribution range of the pores was wider than that of the bamboo charcoal. Combining the SEM of unmodified and modified poplar veneer, the results of X-ray photoelectron spectroscopy revealed that actually some TiOz compounds, i.e., 4.08%, are imbedded in the modified poplar veneer.展开更多
基金We greatly acknowledge the National Natural Science Foundation of China for financial support.
文摘The sonocatalytic damage of bovine serum albumin （BSA） was studied in the presence of nanometer titanium dioxide （TiO2） powders by low frequency （80 kHz） ultrasound. The destruction of secondary structure and change of α-helical structure of BSA were reflected by ultraviolet （UV） and circular dichroism （CD） spectroscopies.
文摘In this work we have developed an analytical method to measure potential titanium debris released from TiO2 nanotube layers devices immersed in biological fluids. This quantitative study is highly required to ensure both the security and non toxicity of the nanostructured surfaces used as future implantable medical devices in the living. A one-pot synthesis process is developed to produce high quality standard solutions of titanium dioxide nanoparticles in aqueous medium. The elaborated dispersion is then used to fabricate standard solutions in both aqueous and human blood plasma media. The synthesized nanoparticles dispersion was characterized by granulometry. The nanoparticles structure and morphology were then observed using Transmission Electron Microscopy (TEM). Thermogravimetric Analysis (TGA) was used to evaluate the concentration of TiO2 in the suspension. A quantitative routine by the use of Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) is developed. The quantification threshold of titanium species is found to be in the 30 - 40 ppb range. None interference is detected between the particles and the human blood plasma. Using the established quantitative routine, the titanium species release from titania nanotube layers in human blood plasma is evaluated.
文摘A new type of inorganic-polymer materials of epoxy Titanium Dioxide and Zinc Oxide was prepared. In this work, the mechanical properties of polymer composites reinforced with ceramic nanoparticles were investigated. Three points bending tests demonstrated an enhancement in flexural strength and flexural modulus respectively, compared to the pure epoxy. The reinforcement of nanoparticulate materials was Titanium Dioxide and Zinc Oxide with various weight fraction. Experimental tests results indicated that the composite materials have significantly higher modulus of elasticity than the matrix material. It was found that the enhancement in modulus of elasticity was directly proportional to the weight fraction of reinforcement material, and that Zinc Oxide composites have higher modulus of elasticity than Titanium Dioxide composites with equivalent of weight fraction. The wear results showed that nanoparticles improved the wear resistance of epoxy nanocomposites, the Titanium Dioxide matrix particles could improve the wear resistance of the epoxy more efficiently than Zinc Oxide particles. The fatigue test showed that the fatigue resistance of epoxy Zinc Oxide matrix particles was higher than that of Titanium Dioxide matrix particles.
文摘The Dye Sensitized Solar Cell (DSSC) plays an important role because of low material cost, ease of production and high conversion efficiency as compared to other thin-film solar cell technologies. The main objective is to create and find the best configuration of the solar cell based on materials that are inexpensive and highly efficient in solar energy conversion and subsequently test the efficiency of dye sensitized titanium dioxide solar cell. We begin the process with two glass plates coated with Fluorine tin oxide (FTO). Titanium dioxide is applied to the conductive side of one plate and the other plate is coated with graphite. A dye is adsorbed on to the TiO2 layer and then the plates are sandwiched together. A drop of iodide electrolyte is then added between the plates. The tests carried out indoors under a lamp emitting all wavelengths in the visible spectrum were not found to provide consistent data due to substantial heating of the cell. The outdoor tests carried out in natural sunlight exhibited steady voltage at much higher level. Future research will involve the incorporation of quantum dots instead of the organic dye as a sensitizer. Quantum dots have the advantages of providing tunable band gaps and the ability to absorb specific wavelength.
文摘In the present work, composites of poly (methyl methacrylate)/titanium oxide nanoparticles (100/0, 97.5/2.5, 95/5, 92.5/7.5, 90/10 and 0/100 wt/wt%)were prepared to be used as bioequivalent materials according to their importance broad practical and medical applications. Thermal properties as well as X-ray diffraction analyses were employed to characterize the structure properties of such composite. The obtained results showed variations in the glass transition temperature (Tg), the melting temperature (Tm), shape and area of thermal peaks which were attributed to the different degrees of crystallinity and the existence of interactions between PMMA and TiO2 nanoparticle molecules. The XRD patterns showed sharpening of peaks at different concentrations of nano-TiO2 powder with PMMA. This indicated changes in the crystallinity/amorphosity ratio, and also suggested that the miscibility between the amorphous components of homo- polymers PMMA and nano-TiO2 powder is possible.The results showed that nano-TiO2 powder mix with PMMA can improve the thermal stability of the homo-polymer under investigation, lead- ing to interesting technological applications.
基金This research has been partially supported by the Government of Andalusia’s project“Characterization and modelling of the phosphogypsum stacks from Huelva for their environmental management and control”(Ref.:RNM-6300) by National Institution of Higher Education,Science,Technology and Innovation of the Republic of Ecuador-(SENESCYT for its acronym in Spanish)+2 种基金The authors would like to acknowledge the financial support received from the company Tioxide-Huelva by the research projects“Valorization of red gypsum from the industrial production of titanium dioxide”(PROFIT,CIT-310200-2007-47)“Applications of red gypsum and Tionite waste in commercial applications”The authors also thank to the technical staff for the advisory provided in the explanation of the results.
文摘Titanium is a very important element for several industrial applications, being one of the ninth most abundant elements in the Earth’s crust (0.63% wt). In this work it will discuss the different mining and industrial activities involved in the production of titanium dioxide. The first step analyzed will treat about the beneficiation mining process of titanium mineral, and secondly, it will discuss the two main processes of the TiO2 manufacturing (sulphate and chloride routes). In addition, we will show different uses of the titanium dioxide pigment as filler in paper, plastics and rubber industries and as flux in glass manufacture, etc. Finally, we will show that the old wastes are currently called co-products since they were valorized, being commercialized by the Spanish industry of TiO2 production in different fields such as agriculture, civil engineering, or cement manufacturing.
基金supported by the National Natural Science Foundation of China (21203185, 21373209)the National Basic Research Program of China (2014CB239400)
文摘Junctions are an important structure that allows charge separation in solar cells and photocatalysts. Here, we studied the charge transfer at an anatase/rutile TiO2 phase junction using time-resolved photoluminescence spectroscopy. Visible （-S00 nm） and near-infrared （NIR, -830 nm） emissions were monitored to give insight into the photoinduced charges of anatase and rutile in the junction, respectively, New fast photoluminescence decay components appeared in the visible emission of futile-phase dominated TiO2 and in the NIR emission of many mixed phase TiO2samples. The fast decays confirmed that the charge separation occurred at the phase junction. The visible emission intensity from the mixed phase TiO2 increased, revealing that charge transfer from rutile to anatase was the main pathway. The charge separation slowed the microsecond time scale photolumines- cence decay rate for charge carriers in both anatase and rutile. However, the millisecond decay of the charge carriers in anatase TiO2 was accelerated, while there was almost no change in the charge carrier dynamics of rutile TiO2. Thus, charge separation at the anatase/rutile phase junction caused an increase in the charge carrier concentration on a microsecond time scale, because of slower electron-hole recombination. The enhanced photocatalytic activity previously observed at ana- tase/rutile phase junctions is likely caused by the improved charge carrier dynamics we report here. These findings may contribute to the development of improved photocatalytic materials.
基金the CAS Strategic Priority Project(No.XDA13040404)the National Natural Science Foundation of China for Exploring Key Scientific Instrument(No.41827805)the Shandong Key Laboratory of Corrosion Science。
文摘Corrosion protection has become an important issue as the amount of infrastructure construction in marine environment increased.Photocathodic protection is a promising method to reduce the corrosion of metals,and titanium dioxide(TiO2) is the most widely used photoanode.This review summarizes the progress in TiO2 photo gene rated protection in recent years.Different types of semiconductors,including sulfides,metals,metal oxide s,polymers,and other materials,are used to design and modify TiO2.The strategy to dramatically improve the efficiency of photoactivity is proposed,and the mechanism is investigated in detail.Characterization methods are also introduced,including morphology testing,light absorption,photoelectrochemistry,and protected metal observation.This review aims to provide a comprehensive overview of Ti02 development and guide photocathodic protection.
基金the China Scholarship Council(CSC,file no.201706950035)University of Manchester joint studentship for supporting her PhD researchthe CSC for her academic visiting fellowship at The University of Manchester(file no.201708440477)the Foundation of Department of Education of Guangdong Province(No.2017KZDXM085,2018KZDXM070)。
文摘Hydrogen(H2)production from photocatalytic reforming of cellulose is a promising way for sustainable H2 to be generated.Herein,we report a systematic study of the photocatalytic reforming of cellulose over Pt/m-TiO2(i.e.mixed TiO2,80%of anatase and 20%of rutile)catalysts in water.The optimum operation condition was established by studying the effect of Pt loading,catalyst concentration,cellulose concentration and reaction temperature on the gas production rate of H2(r(H2))and CO2(r(CO2)),suggesting an optimum operation condition at 40°C with 1.0 g·L^-1of cellulose and 0.75 g·L^-1of 0.16-Pt/m-TiO2 catalyst(with 0.16 wt%Pt loadting)to achieve a relatively sound photocatalytic performance with rH2=9.95μmol·h^-1.It is also shown that although the photoreforming of cellulose was operated at a relatively mild condition(i.e.with an UV-A lamp irradiation at40°C in the aqueous system),a low loading of Pt at^0.16 wt%on m-TiO2 could promote the H2 production effectively.Additionally,by comparing the reaction order expressed from both r(H2)(a1)and r(CO2)(a2)with respect to cellulose and water,the possible mechanism of H2 production was proposed.
基金A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions for financial support to conduct this research
文摘A type of TiO/bamboo charcoal composite made by a dip-dry method was loaded onto wood veneer with a vacuum- pressure method in order to prepare modified poplar veneer. The pore structure parameters and surface morphology of the TiO2/ bamboo charcoal composite were determined and analyzed by means of a porosimetry analyzer and SEM. The results show that the surface morphology of the composite does not change after being loaded with nano TiO2. However, its specific surface area （359.814 m^2·g^-1）, pore volume （0.317 cm^3.g^-1） and average pore diameter （3.526 nm） increased; particularly the cumulative volume of pores was increased by 65.83%. In addition, the distribution range of the pores was wider than that of the bamboo charcoal. Combining the SEM of unmodified and modified poplar veneer, the results of X-ray photoelectron spectroscopy revealed that actually some TiOz compounds, i.e., 4.08%, are imbedded in the modified poplar veneer.
