Rationale: Endotoxin contamination in conventionally purified water poses serious risks to hemodialysis patients, leading to complications such as inflammation and sepsis. Addressing these risks is essential for enhan...Rationale: Endotoxin contamination in conventionally purified water poses serious risks to hemodialysis patients, leading to complications such as inflammation and sepsis. Addressing these risks is essential for enhancing patient safety and meeting global dialysis water quality standards. Advanced filtration technologies, such as titanium dioxide (TiO₂)-based nanoparticle filters, offer a promising approach to improve water purification processes in renal care. Objectives: This study aimed to develop and evaluate the effectiveness of a TiO₂-based nanoparticle microporous filtration system for hemodialysis water purification. The objectives included analyzing the system’s performance in reducing chemical contaminants (calcium, magnesium, aluminum, and lead) and microbiological contaminants (total viable count [TVC] and endotoxin units [EU]) across multiple renal centers. Methods: Water samples from three renal centers (RC1, RC2, and RC3) were analyzed pre- and post-filtration. TiO₂ nanoparticles were synthesized using the sol-gel method and characterized via Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy with Energy Dispersive X-ray analysis (SEM/EDX). The microporous filter, fabricated with TiO₂ nanoparticles, silicon dioxide, and polyethylene glycol (PEG), was tested for its ability to remove contaminants. Analytical techniques included spectroscopy for chemical analysis and microbiological assays for contaminant quantification. Results: Post-treatment analysis revealed significant reductions in chemical contaminants, with removal efficiencies averaging 78% for calcium, 80% for magnesium, 81% for aluminum, and 76.6% for lead across all centers. Microbiological contamination was also substantially reduced, with 78–80% removal of TVC and 76–84.6% reduction in EU levels. FTIR analysis confirmed the presence of hydroxyl groups critical for adsorption, while SEM/EDX characterization revealed a crystalline structure with a particle size of 1.45 nm, pore size of 4.11 μm, filter height of 2.56 mm, and bulk density of 0.58 g/cm³. Conclusion: The TiO₂-based nanoparticle filtration system demonstrated high efficacy in removing chemical and microbiological contaminants, significantly improving water quality for hemodialysis. These results highlight its potential as a practical solution for renal centers, especially in resource-constrained settings. Further studies are needed to evaluate its long-term performance and feasibility for widespread adoption. Recommendation: Renal centers should consider adopting TiO2-based nanoparticle filters to address persistent water quality challenges. Pilot implementations across diverse settings can provide insights into operational feasibility. Additional research should explore scalability, maintenance requirements, and cost-effectiveness to optimize integration into healthcare systems. Significance Statement: This study introduces a practical and innovative solution to improve hemodialysis water purification. By effectively reducing both chemical and microbiological contaminants, the TiO2-based filtration system has the potential to enhance patient safety and outcomes, particularly in settings where maintaining high water quality standards remains challenging.展开更多
Ordered mesoporous Fe/TiO2 was prepared by an evaporation-induced self-assembly method. The iron ions were in situ embedded in the pore wall of the TiO2 framework. The catalyst has excellent light-assisted Fenton cata...Ordered mesoporous Fe/TiO2 was prepared by an evaporation-induced self-assembly method. The iron ions were in situ embedded in the pore wall of the TiO2 framework. The catalyst has excellent light-assisted Fenton catalytic performance under UV and visible light irradiation. X-ray diffraction and transmission electron microscopy results showed that the TiO2 samples have an ordered two-dimensional hexagonal pore structure and an anatase phase structure with high crystallinity. The ordered pore structure of the TiO2 photocatalyst with a large specific surface area is beneficial to mass transfer and light harvesting. Furthermore, iron ions can be controlled by embedding them into the TiO2 framework to prevent iron ion loss and inactivation. After five cycles, the reaction rate of the ordered mesoporous Fe/TiO2 remained unchanged, indicating that the material has stable performance and broad application prospects for the purification of environmental pollutants.展开更多
TiO_(2)is the dominant and most widely researched photocatalyst for environmental remediation,however,the drawbacks,such as only responding to UV light(<5%of sunlight),low charge separation efficiency,and difficult...TiO_(2)is the dominant and most widely researched photocatalyst for environmental remediation,however,the drawbacks,such as only responding to UV light(<5%of sunlight),low charge separation efficiency,and difficulties in recycling,have severely hindered its practical application.Herein,we synthesized magnetically separable Fe_(3)O_(4)@MoS_(2)@mesoporous TiO_(2)(FMmT)photocatalysts via a simple,green,and template-free solvothermal method combined with ultrasonic hydrolysis.It is found that FMmT possesses a high specific surface area(55.09 m2·g−1),enhanced visible-light responsiveness(~521 nm),and remarkable photogenerated charge separation efficiency.In addition,the photocatalytic degradation efficiencies of FMmT for methylene blue(MB),rhodamine B(RhB),and tetracycline(TC)are 99.4%,98.5%,and 89.3%within 300 min,respectively.The corresponding degradation rates are 4.5,4.3,and 3.1 times higher than those of pure TiO_(2)separately.Owing to the high saturation magnetization(43.1 A·m^(2)·kg^(−1)),FMmT can achieve effective recycling with an applied magnetic field.The improved photocatalytic activity is closely related to the effective transport of photogenerated electrons by the active interlayer MoS_(2) and the electron–hole separation caused by the MoS_(2)@TiO_(2)heterojunction.Meanwhile,the excellent light-harvesting ability and abundant reactive sites of the mesoporous TiO_(2)shell further boost the photocatalytic efficiency of FMmT.This work provides a new approach and some experimental basis for the design and performance improvement of magnetic photocatalysts by innovatively incorporating MoS2 as the active interlayer and integrating it with a mesoporous shell.展开更多
By using the bimodal mesoporous silica(BMMS) as the carrier and butyl titanate as the titanium source, the TiO_2/BMMS catalyst was prepared. The samples were characterized by XRD, XRF, N_2 adsorption and desorption, F...By using the bimodal mesoporous silica(BMMS) as the carrier and butyl titanate as the titanium source, the TiO_2/BMMS catalyst was prepared. The samples were characterized by XRD, XRF, N_2 adsorption and desorption, FTIR, UVvis,SEM, EDS, and TEM techniques. The test results showed that TiO_2 was amorphous, the TiO_2/BMMS catalyst had an ordered bimodal mesoporous structure, and the chemical interaction existed between BMMS and TiO_2. Since the TiO_2/BMMS had a lower band gap, its photocatalytic activity was better than TiO_2. Under UV irradiation a one-pot PODS system was set up, using TiO_2/BMMS as the catalyst, H_2O_2 as the oxidant, and methanol as the solvent. The TiO_2/BMMS catalyst showed better photocatalytic activity than the mono-modal mesoporous TiO_2/SBA-15 catalyst, and the desulfurization rate of dibenzothiophene(DBT) over TiO_2/BMMS catalyst could reach 99._2%. The TiO_2/BMMS catalyst also had so good stability that the desulfurization rate of DBT did not drop apparently after 8 cycles of reusing, and could still be close to 90%.展开更多
Mesoporous semiconducting metal oxides(SMOs)heterojunctions are appealing sensors for gas detecting.However,due to the different hydrolysis and condensation mechanism of every metal precursor and the contradiction bet...Mesoporous semiconducting metal oxides(SMOs)heterojunctions are appealing sensors for gas detecting.However,due to the different hydrolysis and condensation mechanism of every metal precursor and the contradiction between high crystallinity and high surface area,the synthesis of mesoporous SMOs heterojunctions with highly o rdered mesostructures,highly crystallized frameworks,and high surface area remains a huge challenge.In this work,we develop a novel"acid-base pair"adjusted solvent evaporation induced self-assembly(EISA)strategy to prepare highly crystallized ordered mesoporous TiO2/WO3(OM-TiO2/WO3)heterojunctions.The WCl6 and titanium isopropoxide(TIPO)are used as the precursors,respectively,which function as the"acid-base pair",enabling the coassembly with the structure directing agent(PEO-b-PS)into highly ordered meso structures.In addition,PEO-b-PS can be converted to rigid carbon which can protect the meso structures from collapse during the crystallization process.The resultant OM-TiO2/WO3 heterojunctions possess primitive cubic mesostructures,large pore size(~21.1 nm),highly crystalline frameworks and surface area(~98 m2/g).As a sensor for acetone,the obtained OM-TiO2/WO3 show excellent re sponse/recovery perfo rmance(3 s/5 s),good linear dependence,repeatability,selectivity,and long-term stability(35 days).展开更多
We synthesized a mesoporous film based on TiO2-reduced graphene oxide(RGO)hybrids using a one-step vapor-thermal method without the need for an additional annealing process.The vapor-thermally prepared TiO2-graphene h...We synthesized a mesoporous film based on TiO2-reduced graphene oxide(RGO)hybrids using a one-step vapor-thermal method without the need for an additional annealing process.The vapor-thermally prepared TiO2-graphene hybrid(VTH)features unique structures with an ultra-large specific surface area of^260 m^2 g^-1 and low aggregation,giving rise to enhanced light harvesting and increased charge generation and separation efficiency.It was observed that a mesoporous film with uniform pore distribution is simultaneously obtained during the VTH growth process.When a 5.0 wt%RGO VTH film was used as the active layer in photocatalysis,the highest photocatalytic activity for degradation of methyl orange was achieved.For another,when a 0.75 wt%RGO VTH film was used as the photoanode in a dye-sensitized solar cell,the power conversion efficiency reached 7.58%,which represents an increase of 73.1%compared to a solar cell using an a photoanode of pure TiO2 synthesized by a traditional solvothermal method.It is expected that this facile method for the synthesis of TiO2/graphene hybrid mesoporous films will be useful in practical applications for preparing other metal oxide/graphene hybrids with ultra-high photocatalytic activity and photovoltaic performance.展开更多
Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporo...Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporous TiO2) with superior photocatalytic hydrogen evolution capability through the synergistic impact of NiS/Ni3S4 (NiSx) cocatalyst and efficient hole scavenger has been demonstrated. The photocatalytic hydrogen evolution of TiO2-NiSx hybrids with the different content of NiSx and upon different organic hole scavengers was both investigated. The hybrid of TiO2 decorated with 3%(mole ratio of Ni^2+) NiSx cocatalyst in methanol solution showed the optimal photocatalytic hydrogen evolution rate of 981.59 μmol h^-1 g^-1 which was about 20 times higher than that of bare mesoporous TiO2. Our results suggested that the boosted hydrogen production performance is attributed to both the improved photoinduced electrons migration between NiS and Ni3S4 in cocatalyst and the high hole captured efficiency by hole scavengers of methanol.展开更多
Single crystal anatase TiO2 nanospindles （NSs） with highly exposed {101} facets were synthesized and employed as electron transport materials （ETMs） in perovskite solar cells （PSCs）. Time-resolved photoluminesce...Single crystal anatase TiO2 nanospindles （NSs） with highly exposed {101} facets were synthesized and employed as electron transport materials （ETMs） in perovskite solar cells （PSCs）. Time-resolved photoluminescence （TRPL） spectra revealed that the TiO2 NSs are more effective than TiO2 nanoparticles in accepting electrons from perovskite. Moreover. the TiO2 nanospindles further endowed the PSCs with good reproducibility and suppressed hysteresis. The best device with TiO2 NSs as ETMs yielded power conversion efficiency （PCE） of 19.6%, demonstrating that the home-made TiO2 NSs is a good ETM for PSCs.展开更多
Currently, lithium–sulfur batteries su er from several critical limitations that hinder their practical application, such as the large volumetric expansion of electrode, poor conductivity and lower sulfur utilization...Currently, lithium–sulfur batteries su er from several critical limitations that hinder their practical application, such as the large volumetric expansion of electrode, poor conductivity and lower sulfur utilization. In this work, TiO2 nanofibers with mesoporous structure have been synthesized by electrospinning and heat treating. As the host material of cathode for Li–S battery, the as prepared samples with novelty structure could enhance the conductivity of cathode composite, promote the utilization of sulfur, and relieve volume expansion for improving the electrochemical property. The initial discharge capacity of TiO2/S composite cathode is 703 mAh/g and the capacity remained at 652 mAh/g after 200 cycles at 0.1 C, whose the capacity retention remains is at 92.7%, demonstrating great prospect for application in high-performance Li–S batteries.展开更多
It has been demonstrated that the conductivity and electrochemical properties of TiO2 nanomate rials can be significantly improved by an incorporation of carbon additives.In the study,we develop a novel Ndoped TiO2 me...It has been demonstrated that the conductivity and electrochemical properties of TiO2 nanomate rials can be significantly improved by an incorporation of carbon additives.In the study,we develop a novel Ndoped TiO2 mesoporous nanostructure via the addition of carbon quantum dots(CQDs)solution following a scalable hydrothermal process.The as-made TiO2 product shows well-defined morphology,high conductivity,large surface area,and abundant mesopores.When evaluated as anodes for sodiumion batteries,the CQDs@TiO2 product annealed at 500℃exhibits a superior sodium storage capability.It delivers a high reversible capacity of 168.8 mAh/g at 100 mA/g over 500 cycles and long cycling stability.The remarkable performance of CQDs@TiO2 mainly arises from the large surface area and mesoporous architecture constructed by ultrathin TiO2 nanosheets,as well as the full coope ration between CQDs and TiO2.展开更多
Hollow mesoporous TiO2 spheres(THs)were prepared via template-directed deposition of TiO2 nanoparticles on the surface of carbon spheres.The carbon spheres were used as hard templates.Their diameters were controlled b...Hollow mesoporous TiO2 spheres(THs)were prepared via template-directed deposition of TiO2 nanoparticles on the surface of carbon spheres.The carbon spheres were used as hard templates.Their diameters were controlled by pH adjustment prior to a hydrothermal process.Physical properties,such as crystallinity,optical characteristics,microstructure and surface morphology of the samples were characterized.The results showed that the diameter of the carbon template could be well controlled in the range of 397-729 nm by adjusting the initial pH value of the dextrose solution from 3 to 10.Hollow TiO2 spheres with average diameters ranging from 171 to 668 nm and shell thicknesses ranging from 28 to 47 nm formed by heat treatment at 450℃.The photocatalytic performance of hollow TiO2 spheres and TiO2 nanoparticles was examined under UVA irradiation using a methyl orange aqueous solution as an artificial dye.The study revealed that the THs synthesized using a dextrose solution at pH 7 had a higher photocatalytic activity compared to other samples since it had the lowest shell thickness and the proper optical band gap of 3.12 eV with the longest lifetime of electron-hole pair separation.展开更多
Ag loaded mesoporous silica-embedded TiO_2 nanocomposites were successfully synthesized via two different routes,including one-pot solvothermal method and solvothermal-chemical reduction method,both using Titanium（Ⅳ...Ag loaded mesoporous silica-embedded TiO_2 nanocomposites were successfully synthesized via two different routes,including one-pot solvothermal method and solvothermal-chemical reduction method,both using Titanium（Ⅳ） n-butoxide（Ti（OC_4H_9）_4） as a precursor,formic acid as a solvent and reducing agent,silver nitrate as a silver source and tetraethyl silicate（TEOS） as a stabilizer.The transmission electron microscopic（TEM） images showed that silica-embedded anatase TiO_2 sample exhibited approximately rhombic shape and Ag nanoparticles could be embedded into the nanocomposites or deposited on the surface with high dispersion.The N_2 adsorption-desorption isotherms indicated that the silica-embedded anatase TiO_2 had obvious mesoporous structure with a BET specific surface area of 203.5 m^2·g^-1.All Ag loaded silica-embedded TiO_2composites showed a higher photocatalytic H2-generation activity from water splitting under simulative solar light irradiation than that of TiO2 products.The maximum H_2 production rate（6.10 mmol·h^-1·g^-1） was obtained over 2%Ag/silica-embedded TiO2 nanocomposites（2%Ag/MST） prepared by solvothermal-chemical reduction method,which was 20 times that achieved on the silica-embedded TiO2 sample.The enhanced photocatalytic H2-evolution activity of Ag loaded mesoporous silica-embedded TiO2 nanocomposites can be attributed to the multi-function of surface Ag co-catalyst,mesoporous structure,and embedding of silica.展开更多
An Fe/TiO2catalyst with uniform mesopores was synthesized using Pluronic F127as a structuredirecting agent.This catalyst was used for selective catalytic reduction of NO with NH3.The catalytic activity and resistance ...An Fe/TiO2catalyst with uniform mesopores was synthesized using Pluronic F127as a structuredirecting agent.This catalyst was used for selective catalytic reduction of NO with NH3.The catalytic activity and resistance to H2O and SO2of Fe/TiO2prepared by a template method were better than those of catalysts synthesized using impregnation and coprecipitation.The samples were characterized using N2‐physisorption,transmission electron microscopy,ultraviolet‐visibl spectroscopy,X‐ray photoelectron spectroscopy,and in situ diffuse reflectance infrared Fouriertransform spectroscopy.The results showed that Pluronic F127acted as a structural and chemical promoter;it not only promoted the formation of a uniform mesoporous structure,leading to a higher surface area,but also improved dispersion of the active phase.In addition,the larger number of Lewis acidic sites,indicated by the presence of coordinated NH3species(1188cm-1)and the N–H stretching modes of coordinated NH3(3242and3388cm-1),were beneficial to mid‐temperature selective catalytic reduction reactions.展开更多
The mesoporous Ti O2 has been synthesized by evaporation induced self assembly(EISA) method. The thermogravimetric/differential scanning calorimetric(TG/DSC), X-ray diffraction(XRD), high-resolution transmission elect...The mesoporous Ti O2 has been synthesized by evaporation induced self assembly(EISA) method. The thermogravimetric/differential scanning calorimetric(TG/DSC), X-ray diffraction(XRD), high-resolution transmission electron microscopy(HR-TEM) and N2 adsorption desorption and adsorption are used to study the effects of the synthesized process condition on the microstructure of the as-synthesized mesoporous Ti O2. The photocatalytic performances of as-synthesized samples are evaluated by the degradation of the formaldehyde under ultraviolet light irradiations. The results demonstrate that the as-synthesized mesoporous Ti O2 are anatase with the uniform size about 20-40 nm. The sample is prepared using cetyltrimethyl ammonium bromide(CTAB) as the template with average pore size distribution of 8.12 nm, specific surface area of 68.47 m2/g and pore volume of 0.213 m L/g. The samples show decomposition of formaldehyde 95.8% under ultraviolet light irradiations for 90 min. These results provide a basic experimental process for preparation mesoporous Ti O2, which will posses a broad prospect in terms of the applications in improving indoor air quality.展开更多
Mesoporous anatase TiO2 spheres with high surface area（119 m^2g^（-1）） were successfully synthesized via a facile and green template-free method. The prepared TiO2 was characterized by X-ray diffraction（XRD）,N2 a...Mesoporous anatase TiO2 spheres with high surface area（119 m^2g^（-1）） were successfully synthesized via a facile and green template-free method. The prepared TiO2 was characterized by X-ray diffraction（XRD）,N2 adsorption, scanning electron microscopy（SEM）, transmission electron microscopy（TEM） and UV–vis absorbance spectra. It was found that the prepared TiO2 is characterized by pure anatase phase, which shows uniform spheres and has a typical mesostructure with a high specific surface area and a large pore volume. The effects of complexant（acetylacetone） amount, crystallization temperature and calcination temperature were also investigated. Based on the results, a sketch for the preparation of mesoporous TiO2 was proposed. First, complex formed between tetrabutyl titanate and acetylacetone in ethanol. After introduction of aqueous of ammonia sulfate and urea, hydrolysis of tetrabutyl titanate would occur slowly,and sol of TiO2 was formed. Then, crystallization proceeded under hydrothermal conditions. Calcination process favored the formation of bigger TiO2 crystal through combining of the small crystals in TiO2.This led to the formation of bigger mesopores between TiO2 crystals. Photocatalytic activity of the prepared TiO2 was evaluated by decomposition of methyl orange.展开更多
Highly active mesoporous TiO_2 of about 6 nm crystal size and 280.7 m^2/g specific surface areas has been successfully synthesized via controlled hydrolysis of titanium butoxide at acidic medium. It was characterized ...Highly active mesoporous TiO_2 of about 6 nm crystal size and 280.7 m^2/g specific surface areas has been successfully synthesized via controlled hydrolysis of titanium butoxide at acidic medium. It was characterized by means of XRD（X-ray diffraction）, SEM（scanning electron microscopy）, TEM（transmission electron microscopy）, FT-IR（Fourier transform infrared spectroscopy）, TGA（thermogravimetric analysis）, DSC（differential scanning calorimetry） and BET（Brunauer–Emmett–Teller） surface area. The degradation of dichlorophenol-indophenol（DCPIP） under ultraviolet（UV） light was studied to evaluate the photocatalytic activity of samples. The effects of different parameters and kinetics were investigated. Accordingly, a complete degradation of DCPIP dye was achieved by applying the optimal operational conditions of 1 g/L of catalyst, 10 mg/L of DCPIP, pH of 3 and the temperature at 25 ± 3°C after 3 min under UV irradiation. Meanwhile, the Langmuir–Hinshelwood kinetic model described the variations in pure photocatalytic branch in consistent with a first order power law model.The results proved that the prepared TiO_2 nanoparticle has a photocatalytic activity significantly better than Degussa P-25.展开更多
Mesoporous TiO_2-B/anatase microparticles have been in-situ synthesized from K_2Ti_2O_5 without template.The TiO_2-B phase around the particle surface accelerates the diffusion of charges through the interface,while t...Mesoporous TiO_2-B/anatase microparticles have been in-situ synthesized from K_2Ti_2O_5 without template.The TiO_2-B phase around the particle surface accelerates the diffusion of charges through the interface,while the anatase phase in the core maintains the capacity stability.The heterojunction interface between the main polymorph of anatase and the trace of TiO_2-B exhibits promising lithium ion battery performance.This trace of 5%(by mass) TiO_2-B determined by Raman spectra brings the first discharge capacity of this material to 247 mA · h ·g^(-1),giving 20%improvement compared to the anatase counterpart Stability testing at 1 C reveals that the capacity maintains at 171 mA·h·^(-1),which is better than 162 mA·h·g^(-1) for single phase anatase or 159 mA·h·g^(-1) for TiO_2-B.The mesoporous TiO_2-B/anatase rnicroparticles also show superior rate performance with 100 mA·h·g^(-1) at 40 C,increased by nearly 25%as compared to pure anatase.This opens a possibility of a general design route,which can be applied to other metal oxide electrode materials for rechargeable batteries and supercapacitors.展开更多
Much attention has been paid to the pollutant dimethylarsenic acid(DMA),because of its high toxicity even at very low doses.Although TiO2 photocatalytic oxidation(PCO)is one of the few effective methods for treating D...Much attention has been paid to the pollutant dimethylarsenic acid(DMA),because of its high toxicity even at very low doses.Although TiO2 photocatalytic oxidation(PCO)is one of the few effective methods for treating DMA-containing water,the efficient decomposition of DMA and simultaneous removal of toxic arsenic species remains a significant but challenging task.Here,defective mesoporous TiO2 with mixed-phase structure was synthesized and used as both photocatalyst and adsorbent for DMA removal.Due to the reduced band-gap and enhanced separation of photogenerated charge carriers,the oxygen-deficient TiO2 nanostructures exhibited 4.2 times higher PCO efficiency than commercial TiO2(P25).More importantly,the high surface area of the mesoporous TiO2 provided sufficient active sites for in-situ adsorption and reaction,resulting in the efficient removal of as-formed As(V).Combining the experimental and characterization results,the different roles of reactive species during PCO reactions were clarified.In the presence of hole(h+)as the dominant oxidation species,DMA was demethylated and transformed into MMA.Thereafter,MMA was subsequently reduced to As(Ⅲ)by photo-generated electrons.Superoxide radicals(O2·-)played a significant role in oxidizing As(Ⅲ)into As(Ⅴ),which was finally adsorptively removed by the mesoporous TiO2.展开更多
Mesoporous TiO2 （m-TiO2） nanoparticles were used to prepare the porous film electrodes for dye-sensitized solar cells, and a second metal oxide （MgO, ZnO, A1203, or NiO） modifi- cation was carried out by dipping t...Mesoporous TiO2 （m-TiO2） nanoparticles were used to prepare the porous film electrodes for dye-sensitized solar cells, and a second metal oxide （MgO, ZnO, A1203, or NiO） modifi- cation was carried out by dipping the m-TiO2 electrode into their respective nitrate solution followed by annealing at 500 ℃. Experimental results indicated that the above second metal oxide modifications on m-TiO2 electrode are shown in all cases to act as barrier layer for the interracial charge transfer processes, but film electron transport and interfacial charge recombination characteristics under applied bias voltage were dependent significantly on the existing states and kinds of these second metal oxides. Those changes based on sec- ond metal oxide modifications showed good correlation with the current-voltage analyses of dye-sensitized solar cell, and all modifications were found to increase the open-circuit photo- voltage in various degrees, while the MgO, ZnO, and NiO modifications result in 23%, 13%, and 6% improvement in cell conversion efficiency, respectively. The above observations indi- cate that controlling the charge transport and recombination is very important to improve the photovoltaic performance of TiO2-based solar cell.展开更多
In this work, electrospray technique combined sol-gel method was used to prepare porous TiO2 film. X-ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM) analyses were ...In this work, electrospray technique combined sol-gel method was used to prepare porous TiO2 film. X-ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM) analyses were conducted to examine the chemical composition, phase structure, and surface morphology of the sprayed TiO2 film. After calcined at 450℃ in air atmosphere for 2 h, mesoporous TiO2 nano-spheres clusters were formed on the surface of silicon wafer and the average size of nano-spheres was 250 nm. Ti presented as Ti 4+ oxidation state in TiO2 film, and the TiO2 film exhibited the anatase phase. The sprayed porous TiO2 films were employed as photocatalyst to degrade organic phosphorus in water samples. Compared with the TiO2 film prepared by Sol-Gel spin-coating method, the porous TiO2 film deposited by electrospray combined sol-gel method showed higher photocatalytic activity.展开更多
文摘Rationale: Endotoxin contamination in conventionally purified water poses serious risks to hemodialysis patients, leading to complications such as inflammation and sepsis. Addressing these risks is essential for enhancing patient safety and meeting global dialysis water quality standards. Advanced filtration technologies, such as titanium dioxide (TiO₂)-based nanoparticle filters, offer a promising approach to improve water purification processes in renal care. Objectives: This study aimed to develop and evaluate the effectiveness of a TiO₂-based nanoparticle microporous filtration system for hemodialysis water purification. The objectives included analyzing the system’s performance in reducing chemical contaminants (calcium, magnesium, aluminum, and lead) and microbiological contaminants (total viable count [TVC] and endotoxin units [EU]) across multiple renal centers. Methods: Water samples from three renal centers (RC1, RC2, and RC3) were analyzed pre- and post-filtration. TiO₂ nanoparticles were synthesized using the sol-gel method and characterized via Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy with Energy Dispersive X-ray analysis (SEM/EDX). The microporous filter, fabricated with TiO₂ nanoparticles, silicon dioxide, and polyethylene glycol (PEG), was tested for its ability to remove contaminants. Analytical techniques included spectroscopy for chemical analysis and microbiological assays for contaminant quantification. Results: Post-treatment analysis revealed significant reductions in chemical contaminants, with removal efficiencies averaging 78% for calcium, 80% for magnesium, 81% for aluminum, and 76.6% for lead across all centers. Microbiological contamination was also substantially reduced, with 78–80% removal of TVC and 76–84.6% reduction in EU levels. FTIR analysis confirmed the presence of hydroxyl groups critical for adsorption, while SEM/EDX characterization revealed a crystalline structure with a particle size of 1.45 nm, pore size of 4.11 μm, filter height of 2.56 mm, and bulk density of 0.58 g/cm³. Conclusion: The TiO₂-based nanoparticle filtration system demonstrated high efficacy in removing chemical and microbiological contaminants, significantly improving water quality for hemodialysis. These results highlight its potential as a practical solution for renal centers, especially in resource-constrained settings. Further studies are needed to evaluate its long-term performance and feasibility for widespread adoption. Recommendation: Renal centers should consider adopting TiO2-based nanoparticle filters to address persistent water quality challenges. Pilot implementations across diverse settings can provide insights into operational feasibility. Additional research should explore scalability, maintenance requirements, and cost-effectiveness to optimize integration into healthcare systems. Significance Statement: This study introduces a practical and innovative solution to improve hemodialysis water purification. By effectively reducing both chemical and microbiological contaminants, the TiO2-based filtration system has the potential to enhance patient safety and outcomes, particularly in settings where maintaining high water quality standards remains challenging.
基金supported by the National Natural Science Foundation of China(21876114,21761142011,51572174)Shanghai Government(17SG44)+2 种基金International Joint Laboratory on Resource Chemistry(IJLRC)Ministry of Education of China(PCSIRT_IRT_16R49)supported by The Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning and Shuguang Research Program of Shanghai Education Committee~~
文摘Ordered mesoporous Fe/TiO2 was prepared by an evaporation-induced self-assembly method. The iron ions were in situ embedded in the pore wall of the TiO2 framework. The catalyst has excellent light-assisted Fenton catalytic performance under UV and visible light irradiation. X-ray diffraction and transmission electron microscopy results showed that the TiO2 samples have an ordered two-dimensional hexagonal pore structure and an anatase phase structure with high crystallinity. The ordered pore structure of the TiO2 photocatalyst with a large specific surface area is beneficial to mass transfer and light harvesting. Furthermore, iron ions can be controlled by embedding them into the TiO2 framework to prevent iron ion loss and inactivation. After five cycles, the reaction rate of the ordered mesoporous Fe/TiO2 remained unchanged, indicating that the material has stable performance and broad application prospects for the purification of environmental pollutants.
基金financially supported by the National Key R & D Projects (Nos. 2021YFC1910504, 2019YFC1907101, 2019YFC1907103, and 2017YFB0702304)the Key R & D Project in Ningxia Hui Autonomous Region, China (No. 2020BCE01001)+6 种基金the Key and Normal Projects National Natural Science Foundation of China (Nos. U2002212 and 51672024)the Xijiang Innovation and Entrepreneurship Team (No. 2017A0109004)the Fundamental Research Funds for the Central Universities (Nos. FRF-BD-20-24A, FRF-TP-20-031A1, FRF-IC-19-017Z, FRF-GF-19-032B, and 06500141)the Integration of Green Key Process Systems MIIT, Natural Science Foundation of Beijing Municipality (No. 2214073)the Guangdong Basic and Applied Research Foundation, China (No. 2020A1515110408)the Foshan Science and Technology Innovation Special Foundation, China (No. BK21BE002)the Postdoctor Research Foundation of Shunde Graduate School of University of Science and Technology Beijing (No. 2020BH004)
文摘TiO_(2)is the dominant and most widely researched photocatalyst for environmental remediation,however,the drawbacks,such as only responding to UV light(<5%of sunlight),low charge separation efficiency,and difficulties in recycling,have severely hindered its practical application.Herein,we synthesized magnetically separable Fe_(3)O_(4)@MoS_(2)@mesoporous TiO_(2)(FMmT)photocatalysts via a simple,green,and template-free solvothermal method combined with ultrasonic hydrolysis.It is found that FMmT possesses a high specific surface area(55.09 m2·g−1),enhanced visible-light responsiveness(~521 nm),and remarkable photogenerated charge separation efficiency.In addition,the photocatalytic degradation efficiencies of FMmT for methylene blue(MB),rhodamine B(RhB),and tetracycline(TC)are 99.4%,98.5%,and 89.3%within 300 min,respectively.The corresponding degradation rates are 4.5,4.3,and 3.1 times higher than those of pure TiO_(2)separately.Owing to the high saturation magnetization(43.1 A·m^(2)·kg^(−1)),FMmT can achieve effective recycling with an applied magnetic field.The improved photocatalytic activity is closely related to the effective transport of photogenerated electrons by the active interlayer MoS_(2) and the electron–hole separation caused by the MoS_(2)@TiO_(2)heterojunction.Meanwhile,the excellent light-harvesting ability and abundant reactive sites of the mesoporous TiO_(2)shell further boost the photocatalytic efficiency of FMmT.This work provides a new approach and some experimental basis for the design and performance improvement of magnetic photocatalysts by innovatively incorporating MoS2 as the active interlayer and integrating it with a mesoporous shell.
基金financially supported by the Program for Liaoning Excellent Talents in University,abbreviated as“LNET”(LJQ2015062)Program for Science and Technology Agency of Liaoning Province(20170540585)+1 种基金General Scientific Research Project of Liaoning Provincial Department of Education(L2015296,L2016018)Science and Technology Planning project of Fushun(FSKJHT201376)
文摘By using the bimodal mesoporous silica(BMMS) as the carrier and butyl titanate as the titanium source, the TiO_2/BMMS catalyst was prepared. The samples were characterized by XRD, XRF, N_2 adsorption and desorption, FTIR, UVvis,SEM, EDS, and TEM techniques. The test results showed that TiO_2 was amorphous, the TiO_2/BMMS catalyst had an ordered bimodal mesoporous structure, and the chemical interaction existed between BMMS and TiO_2. Since the TiO_2/BMMS had a lower band gap, its photocatalytic activity was better than TiO_2. Under UV irradiation a one-pot PODS system was set up, using TiO_2/BMMS as the catalyst, H_2O_2 as the oxidant, and methanol as the solvent. The TiO_2/BMMS catalyst showed better photocatalytic activity than the mono-modal mesoporous TiO_2/SBA-15 catalyst, and the desulfurization rate of dibenzothiophene(DBT) over TiO_2/BMMS catalyst could reach 99._2%. The TiO_2/BMMS catalyst also had so good stability that the desulfurization rate of DBT did not drop apparently after 8 cycles of reusing, and could still be close to 90%.
基金supported by the National Natural Science Foundation of China(Nos.51822202 and 51772050)China Postdoctoral Science Foundation(No.2019M651342)+2 种基金Shanghai Rising-Star Program(No.18QA1400100)Youth Top-notch Talent Support Program of Shanghai,the Shanghai Committee of Science and Technology,China(No.19520713200)DHU Distinguished Young Professor Program and Fundamental Research Funds for the Central Universities。
文摘Mesoporous semiconducting metal oxides(SMOs)heterojunctions are appealing sensors for gas detecting.However,due to the different hydrolysis and condensation mechanism of every metal precursor and the contradiction between high crystallinity and high surface area,the synthesis of mesoporous SMOs heterojunctions with highly o rdered mesostructures,highly crystallized frameworks,and high surface area remains a huge challenge.In this work,we develop a novel"acid-base pair"adjusted solvent evaporation induced self-assembly(EISA)strategy to prepare highly crystallized ordered mesoporous TiO2/WO3(OM-TiO2/WO3)heterojunctions.The WCl6 and titanium isopropoxide(TIPO)are used as the precursors,respectively,which function as the"acid-base pair",enabling the coassembly with the structure directing agent(PEO-b-PS)into highly ordered meso structures.In addition,PEO-b-PS can be converted to rigid carbon which can protect the meso structures from collapse during the crystallization process.The resultant OM-TiO2/WO3 heterojunctions possess primitive cubic mesostructures,large pore size(~21.1 nm),highly crystalline frameworks and surface area(~98 m2/g).As a sensor for acetone,the obtained OM-TiO2/WO3 show excellent re sponse/recovery perfo rmance(3 s/5 s),good linear dependence,repeatability,selectivity,and long-term stability(35 days).
文摘We synthesized a mesoporous film based on TiO2-reduced graphene oxide(RGO)hybrids using a one-step vapor-thermal method without the need for an additional annealing process.The vapor-thermally prepared TiO2-graphene hybrid(VTH)features unique structures with an ultra-large specific surface area of^260 m^2 g^-1 and low aggregation,giving rise to enhanced light harvesting and increased charge generation and separation efficiency.It was observed that a mesoporous film with uniform pore distribution is simultaneously obtained during the VTH growth process.When a 5.0 wt%RGO VTH film was used as the active layer in photocatalysis,the highest photocatalytic activity for degradation of methyl orange was achieved.For another,when a 0.75 wt%RGO VTH film was used as the photoanode in a dye-sensitized solar cell,the power conversion efficiency reached 7.58%,which represents an increase of 73.1%compared to a solar cell using an a photoanode of pure TiO2 synthesized by a traditional solvothermal method.It is expected that this facile method for the synthesis of TiO2/graphene hybrid mesoporous films will be useful in practical applications for preparing other metal oxide/graphene hybrids with ultra-high photocatalytic activity and photovoltaic performance.
基金the National Natural Science Foundation of China(21501137)the Hubei Natural Science Foundation for financial support(2018CFB680)Support from the Australian Research Council(ARC)through ARC Discovery projects(DP130102699,DP 130102274,DP160102627)
文摘Photocatalytic solar energy conversion to hydrogen is sustainable and attractive for addressing the global energy and environmental issue. Herein, a novel photocatalytic system (NiS/Ni3S4 cocatalysts modified mesoporous TiO2) with superior photocatalytic hydrogen evolution capability through the synergistic impact of NiS/Ni3S4 (NiSx) cocatalyst and efficient hole scavenger has been demonstrated. The photocatalytic hydrogen evolution of TiO2-NiSx hybrids with the different content of NiSx and upon different organic hole scavengers was both investigated. The hybrid of TiO2 decorated with 3%(mole ratio of Ni^2+) NiSx cocatalyst in methanol solution showed the optimal photocatalytic hydrogen evolution rate of 981.59 μmol h^-1 g^-1 which was about 20 times higher than that of bare mesoporous TiO2. Our results suggested that the boosted hydrogen production performance is attributed to both the improved photoinduced electrons migration between NiS and Ni3S4 in cocatalyst and the high hole captured efficiency by hole scavengers of methanol.
基金supported by the National Natural Science Foundation of China(Grand No.21773128)Key Research and Development Projects of Sichuan Province(Grand No.2017GZ0052)+1 种基金National Postdoctoral Program for Innovative Talents(BX201600138)Anshan Hifichem Co.,Ltd
文摘Single crystal anatase TiO2 nanospindles （NSs） with highly exposed {101} facets were synthesized and employed as electron transport materials （ETMs） in perovskite solar cells （PSCs）. Time-resolved photoluminescence （TRPL） spectra revealed that the TiO2 NSs are more effective than TiO2 nanoparticles in accepting electrons from perovskite. Moreover. the TiO2 nanospindles further endowed the PSCs with good reproducibility and suppressed hysteresis. The best device with TiO2 NSs as ETMs yielded power conversion efficiency （PCE） of 19.6%, demonstrating that the home-made TiO2 NSs is a good ETM for PSCs.
基金Supported by National Nature Science Foundation of China(Grant No.61774022)Education Department of Jilin Province of China(Grant No.JJKH20181030KJ)
文摘Currently, lithium–sulfur batteries su er from several critical limitations that hinder their practical application, such as the large volumetric expansion of electrode, poor conductivity and lower sulfur utilization. In this work, TiO2 nanofibers with mesoporous structure have been synthesized by electrospinning and heat treating. As the host material of cathode for Li–S battery, the as prepared samples with novelty structure could enhance the conductivity of cathode composite, promote the utilization of sulfur, and relieve volume expansion for improving the electrochemical property. The initial discharge capacity of TiO2/S composite cathode is 703 mAh/g and the capacity remained at 652 mAh/g after 200 cycles at 0.1 C, whose the capacity retention remains is at 92.7%, demonstrating great prospect for application in high-performance Li–S batteries.
基金financial support from the Shuguang Program supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.18SG035)Shanghai Pujiang Program(No.17PJD015)。
文摘It has been demonstrated that the conductivity and electrochemical properties of TiO2 nanomate rials can be significantly improved by an incorporation of carbon additives.In the study,we develop a novel Ndoped TiO2 mesoporous nanostructure via the addition of carbon quantum dots(CQDs)solution following a scalable hydrothermal process.The as-made TiO2 product shows well-defined morphology,high conductivity,large surface area,and abundant mesopores.When evaluated as anodes for sodiumion batteries,the CQDs@TiO2 product annealed at 500℃exhibits a superior sodium storage capability.It delivers a high reversible capacity of 168.8 mAh/g at 100 mA/g over 500 cycles and long cycling stability.The remarkable performance of CQDs@TiO2 mainly arises from the large surface area and mesoporous architecture constructed by ultrathin TiO2 nanosheets,as well as the full coope ration between CQDs and TiO2.
基金financially supported by Mahasarakham University in 2020。
文摘Hollow mesoporous TiO2 spheres(THs)were prepared via template-directed deposition of TiO2 nanoparticles on the surface of carbon spheres.The carbon spheres were used as hard templates.Their diameters were controlled by pH adjustment prior to a hydrothermal process.Physical properties,such as crystallinity,optical characteristics,microstructure and surface morphology of the samples were characterized.The results showed that the diameter of the carbon template could be well controlled in the range of 397-729 nm by adjusting the initial pH value of the dextrose solution from 3 to 10.Hollow TiO2 spheres with average diameters ranging from 171 to 668 nm and shell thicknesses ranging from 28 to 47 nm formed by heat treatment at 450℃.The photocatalytic performance of hollow TiO2 spheres and TiO2 nanoparticles was examined under UVA irradiation using a methyl orange aqueous solution as an artificial dye.The study revealed that the THs synthesized using a dextrose solution at pH 7 had a higher photocatalytic activity compared to other samples since it had the lowest shell thickness and the proper optical band gap of 3.12 eV with the longest lifetime of electron-hole pair separation.
基金Funded by Priority Academic Program Development(PAPD)of Jiangsu Higher Education Institutions
文摘Ag loaded mesoporous silica-embedded TiO_2 nanocomposites were successfully synthesized via two different routes,including one-pot solvothermal method and solvothermal-chemical reduction method,both using Titanium（Ⅳ） n-butoxide（Ti（OC_4H_9）_4） as a precursor,formic acid as a solvent and reducing agent,silver nitrate as a silver source and tetraethyl silicate（TEOS） as a stabilizer.The transmission electron microscopic（TEM） images showed that silica-embedded anatase TiO_2 sample exhibited approximately rhombic shape and Ag nanoparticles could be embedded into the nanocomposites or deposited on the surface with high dispersion.The N_2 adsorption-desorption isotherms indicated that the silica-embedded anatase TiO_2 had obvious mesoporous structure with a BET specific surface area of 203.5 m^2·g^-1.All Ag loaded silica-embedded TiO_2composites showed a higher photocatalytic H2-generation activity from water splitting under simulative solar light irradiation than that of TiO2 products.The maximum H_2 production rate（6.10 mmol·h^-1·g^-1） was obtained over 2%Ag/silica-embedded TiO2 nanocomposites（2%Ag/MST） prepared by solvothermal-chemical reduction method,which was 20 times that achieved on the silica-embedded TiO2 sample.The enhanced photocatalytic H2-evolution activity of Ag loaded mesoporous silica-embedded TiO2 nanocomposites can be attributed to the multi-function of surface Ag co-catalyst,mesoporous structure,and embedding of silica.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA07030300)~~
文摘An Fe/TiO2catalyst with uniform mesopores was synthesized using Pluronic F127as a structuredirecting agent.This catalyst was used for selective catalytic reduction of NO with NH3.The catalytic activity and resistance to H2O and SO2of Fe/TiO2prepared by a template method were better than those of catalysts synthesized using impregnation and coprecipitation.The samples were characterized using N2‐physisorption,transmission electron microscopy,ultraviolet‐visibl spectroscopy,X‐ray photoelectron spectroscopy,and in situ diffuse reflectance infrared Fouriertransform spectroscopy.The results showed that Pluronic F127acted as a structural and chemical promoter;it not only promoted the formation of a uniform mesoporous structure,leading to a higher surface area,but also improved dispersion of the active phase.In addition,the larger number of Lewis acidic sites,indicated by the presence of coordinated NH3species(1188cm-1)and the N–H stretching modes of coordinated NH3(3242and3388cm-1),were beneficial to mid‐temperature selective catalytic reduction reactions.
基金Projects(51102026,51272032) supported by the Program for the National Natural Science Foundation of ChinaProject(11A014) supported by the Scientific Research Fund of Hunan Provincial Education DepartmentProject supported by the Aid Program for Science and Technology Innovative Research Team in Higher Educational Instituions of Hunan Province,China
文摘The mesoporous Ti O2 has been synthesized by evaporation induced self assembly(EISA) method. The thermogravimetric/differential scanning calorimetric(TG/DSC), X-ray diffraction(XRD), high-resolution transmission electron microscopy(HR-TEM) and N2 adsorption desorption and adsorption are used to study the effects of the synthesized process condition on the microstructure of the as-synthesized mesoporous Ti O2. The photocatalytic performances of as-synthesized samples are evaluated by the degradation of the formaldehyde under ultraviolet light irradiations. The results demonstrate that the as-synthesized mesoporous Ti O2 are anatase with the uniform size about 20-40 nm. The sample is prepared using cetyltrimethyl ammonium bromide(CTAB) as the template with average pore size distribution of 8.12 nm, specific surface area of 68.47 m2/g and pore volume of 0.213 m L/g. The samples show decomposition of formaldehyde 95.8% under ultraviolet light irradiations for 90 min. These results provide a basic experimental process for preparation mesoporous Ti O2, which will posses a broad prospect in terms of the applications in improving indoor air quality.
基金supported by the National Natural Science Foundation of China (Nos. 21206150, U1304209 and U1204215)the Foundation for University Young Key Teacher by Henan Province (No. 2014GGJS-005)
文摘Mesoporous anatase TiO2 spheres with high surface area（119 m^2g^（-1）） were successfully synthesized via a facile and green template-free method. The prepared TiO2 was characterized by X-ray diffraction（XRD）,N2 adsorption, scanning electron microscopy（SEM）, transmission electron microscopy（TEM） and UV–vis absorbance spectra. It was found that the prepared TiO2 is characterized by pure anatase phase, which shows uniform spheres and has a typical mesostructure with a high specific surface area and a large pore volume. The effects of complexant（acetylacetone） amount, crystallization temperature and calcination temperature were also investigated. Based on the results, a sketch for the preparation of mesoporous TiO2 was proposed. First, complex formed between tetrabutyl titanate and acetylacetone in ethanol. After introduction of aqueous of ammonia sulfate and urea, hydrolysis of tetrabutyl titanate would occur slowly,and sol of TiO2 was formed. Then, crystallization proceeded under hydrothermal conditions. Calcination process favored the formation of bigger TiO2 crystal through combining of the small crystals in TiO2.This led to the formation of bigger mesopores between TiO2 crystals. Photocatalytic activity of the prepared TiO2 was evaluated by decomposition of methyl orange.
基金funded by the Science and Technology Development Fund (STDF), Ministry of Scientific Research (No. 1414, "Quantum Dots Nanomaterials Dye Sensitized Solar Cells")
文摘Highly active mesoporous TiO_2 of about 6 nm crystal size and 280.7 m^2/g specific surface areas has been successfully synthesized via controlled hydrolysis of titanium butoxide at acidic medium. It was characterized by means of XRD（X-ray diffraction）, SEM（scanning electron microscopy）, TEM（transmission electron microscopy）, FT-IR（Fourier transform infrared spectroscopy）, TGA（thermogravimetric analysis）, DSC（differential scanning calorimetry） and BET（Brunauer–Emmett–Teller） surface area. The degradation of dichlorophenol-indophenol（DCPIP） under ultraviolet（UV） light was studied to evaluate the photocatalytic activity of samples. The effects of different parameters and kinetics were investigated. Accordingly, a complete degradation of DCPIP dye was achieved by applying the optimal operational conditions of 1 g/L of catalyst, 10 mg/L of DCPIP, pH of 3 and the temperature at 25 ± 3°C after 3 min under UV irradiation. Meanwhile, the Langmuir–Hinshelwood kinetic model described the variations in pure photocatalytic branch in consistent with a first order power law model.The results proved that the prepared TiO_2 nanoparticle has a photocatalytic activity significantly better than Degussa P-25.
基金Supported by the Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT 0732)the National Natural Science Foundation of China(21136004,20736002,21176113,20876073)+2 种基金NSFC-RGC(20731160614)China Postdoctoral Science Foundation(20110491407)the National Basic Research Program of China(2009CB623407,2009CB219902 and 2009CB226103)
文摘Mesoporous TiO_2-B/anatase microparticles have been in-situ synthesized from K_2Ti_2O_5 without template.The TiO_2-B phase around the particle surface accelerates the diffusion of charges through the interface,while the anatase phase in the core maintains the capacity stability.The heterojunction interface between the main polymorph of anatase and the trace of TiO_2-B exhibits promising lithium ion battery performance.This trace of 5%(by mass) TiO_2-B determined by Raman spectra brings the first discharge capacity of this material to 247 mA · h ·g^(-1),giving 20%improvement compared to the anatase counterpart Stability testing at 1 C reveals that the capacity maintains at 171 mA·h·^(-1),which is better than 162 mA·h·g^(-1) for single phase anatase or 159 mA·h·g^(-1) for TiO_2-B.The mesoporous TiO_2-B/anatase rnicroparticles also show superior rate performance with 100 mA·h·g^(-1) at 40 C,increased by nearly 25%as compared to pure anatase.This opens a possibility of a general design route,which can be applied to other metal oxide electrode materials for rechargeable batteries and supercapacitors.
基金supported by the National Natural Science Foundation of China(Nos.51678556 and 51578531)the National Key Research&Development Program of China(No.2016YFC0400806)
文摘Much attention has been paid to the pollutant dimethylarsenic acid(DMA),because of its high toxicity even at very low doses.Although TiO2 photocatalytic oxidation(PCO)is one of the few effective methods for treating DMA-containing water,the efficient decomposition of DMA and simultaneous removal of toxic arsenic species remains a significant but challenging task.Here,defective mesoporous TiO2 with mixed-phase structure was synthesized and used as both photocatalyst and adsorbent for DMA removal.Due to the reduced band-gap and enhanced separation of photogenerated charge carriers,the oxygen-deficient TiO2 nanostructures exhibited 4.2 times higher PCO efficiency than commercial TiO2(P25).More importantly,the high surface area of the mesoporous TiO2 provided sufficient active sites for in-situ adsorption and reaction,resulting in the efficient removal of as-formed As(V).Combining the experimental and characterization results,the different roles of reactive species during PCO reactions were clarified.In the presence of hole(h+)as the dominant oxidation species,DMA was demethylated and transformed into MMA.Thereafter,MMA was subsequently reduced to As(Ⅲ)by photo-generated electrons.Superoxide radicals(O2·-)played a significant role in oxidizing As(Ⅲ)into As(Ⅴ),which was finally adsorptively removed by the mesoporous TiO2.
文摘Mesoporous TiO2 （m-TiO2） nanoparticles were used to prepare the porous film electrodes for dye-sensitized solar cells, and a second metal oxide （MgO, ZnO, A1203, or NiO） modifi- cation was carried out by dipping the m-TiO2 electrode into their respective nitrate solution followed by annealing at 500 ℃. Experimental results indicated that the above second metal oxide modifications on m-TiO2 electrode are shown in all cases to act as barrier layer for the interracial charge transfer processes, but film electron transport and interfacial charge recombination characteristics under applied bias voltage were dependent significantly on the existing states and kinds of these second metal oxides. Those changes based on sec- ond metal oxide modifications showed good correlation with the current-voltage analyses of dye-sensitized solar cell, and all modifications were found to increase the open-circuit photo- voltage in various degrees, while the MgO, ZnO, and NiO modifications result in 23%, 13%, and 6% improvement in cell conversion efficiency, respectively. The above observations indi- cate that controlling the charge transport and recombination is very important to improve the photovoltaic performance of TiO2-based solar cell.
基金Supported by the National Basic Research Program of China (No. 2009CB320300)National Natural Science Foundation of China (No. 61072023)National High Technology Research and Development Programs (No.2012AA040506, No. 2012AA101608)
文摘In this work, electrospray technique combined sol-gel method was used to prepare porous TiO2 film. X-ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD), and Scanning Electron Microscope (SEM) analyses were conducted to examine the chemical composition, phase structure, and surface morphology of the sprayed TiO2 film. After calcined at 450℃ in air atmosphere for 2 h, mesoporous TiO2 nano-spheres clusters were formed on the surface of silicon wafer and the average size of nano-spheres was 250 nm. Ti presented as Ti 4+ oxidation state in TiO2 film, and the TiO2 film exhibited the anatase phase. The sprayed porous TiO2 films were employed as photocatalyst to degrade organic phosphorus in water samples. Compared with the TiO2 film prepared by Sol-Gel spin-coating method, the porous TiO2 film deposited by electrospray combined sol-gel method showed higher photocatalytic activity.
