Undoped and Ni–S co-doped mesoporous TiO2 nano materials were synthesized by using sol–gel method.The characteristic features of as prepared catalyst samples were investigated using various advanced spectroscopic an...Undoped and Ni–S co-doped mesoporous TiO2 nano materials were synthesized by using sol–gel method.The characteristic features of as prepared catalyst samples were investigated using various advanced spectroscopic and analytical techniques.The characterization results of the samples revealed that all the samples exhibited anatase phase(XRD),decreasing band gap(2.68 eV)(UV–Vis-DRS),small particle size(9.2 nm)(TEM),high surface area(142.156 m^2·g^-1)(BET),particles with spherical shape and smooth morphology(SEM);there is a frequency shift observed for co-doped sample(FT-IR)and the elemental composition electronic states and position of the doped elements(Ni and S)in the TiO2 lattice analyzed by XPS and EDX.These results supported the photocatalytic degradation of Bismarck Brown Red(BBR)achieved with in 110 min and also exhibited the antibacterial activity on Staphylococcus aureus(MTCC-3160),Pseudomonas fluorescence(MTCC-1688)under visible light irradiation.展开更多
The existence form and effect of La on the phase composition,morphology,recombination of photocarriers,and optical absorptivity of La-F codoped TiO2 were investigated.Experimental results indicate that all the phase c...The existence form and effect of La on the phase composition,morphology,recombination of photocarriers,and optical absorptivity of La-F codoped TiO2 were investigated.Experimental results indicate that all the phase composition of samples is anatase TiO2,the grain sizes decrease with the increasing of La content The catalysts have a well-defined spherical structure with an average size of 12-14 nm,and the doping elements are uniformly dispersed.Compared with pure TiO2,the absorption edge of La1.5F5-TiO2 red shifts from 388 to 437 nm,accordingly the energy gap(Eg) reduces from 32 to 2.84 eV,Besides,the recombination rate of electron-holes in La1.5F5-TiO2 is the weakest among the prepared samples,and the specific surface area of La1.5F5-TiO2 reaches 105.27 m2/g.The apparent reaction rate constant k of La1.5F5-TiO2 for methylene blue(MB) degradation under visible light obtained from the apparent first-order model achieves 0.0166±0.52 min-1,which is greater than 0.0033±0.09 min 1 of TiO2.Moreover,high-resolution transmission electron microscopy(HRTEM) observation reveals that there coexist La2O3 particles in the co-doped TiO2.展开更多
A series of Ce, H3PW12O40 co-doped TiO2 hollow fibers photocatalysts have been prepared by sol-gel method using ammonium ceric nitrate, H3PW12O40 and tetrabutyltitanate as precursors and cotton fibers as template, fol...A series of Ce, H3PW12O40 co-doped TiO2 hollow fibers photocatalysts have been prepared by sol-gel method using ammonium ceric nitrate, H3PW12O40 and tetrabutyltitanate as precursors and cotton fibers as template, followed by calcination at 500 ℃ in N2 atmosphere for 2 h. Scanning electron microscopy, X-ray diffraction, nitrogen adsorption-desorption mea- surements, and UV-Vis spectroscopy are employed to characterize the morphology, crystal structure, surface structure, and optical absorption properties of the samples. The photo- catalytic performance of the samples has been studied by photodegradation phenol in water under UV and visible light irradiation. The results show that the TiO2 fiber materials have hollow structures, and the co-doped TiO2 hollow fibers exhibit higher photocatalytic activities for the degradation of phenol than un-doped, single-doped TiO2 hollow fibers under UV and visible light. In addition, the recyclability of co-doped TiO2 fibers is also confirmed that the TiO2 fiber retains ca. 90% of its activity after being used four times. It is shown that the co-doped TiO2 fibers can be activated by visible light and may be potentially applied to the treatment of water contaminated by organic pollutants. The synergistic effect of Ce and H3PW12O40 co-doping plays an important role in improving the photocatalytic activity.展开更多
Doping engineering is an effective strategy for graphitic carbon nitride(g-C_(3)N_(4))to improve its photocat-alytic hydrogen evolution reaction(HER)performance.In this work,a novel nitrogen and sulfur co-doped g-C_(3...Doping engineering is an effective strategy for graphitic carbon nitride(g-C_(3)N_(4))to improve its photocat-alytic hydrogen evolution reaction(HER)performance.In this work,a novel nitrogen and sulfur co-doped g-C_(3)N_(4)(N,S-g-C_(3)N_(4))is elaborately designed on the basis of theoretical predictions of first-principle density functional theory(DFT).The calculated Gibbs free energy of adsorbed hydrogen(ΔGH∗)for N,S-g-C_(3)N_(4) at the N-doping active sites is extremely close to zero(0.01 eV).Inspired by the theoretical predictions,the N,S-g-C_(3)N_(4) is successfully fabricated through ammonia-rich pyrolysis synthesis strategy,in which ammonia is in-situ obtained by pyrolyzing melamine.Subsequent characterizations indicate that the N,S-g-C_(3)N_(4) possesses high specific surface area,outstanding light utilization,good hydrophilicity,and efficient carrier transfer efficiency.Consequently,the N,S-g-C_(3)N_(4) displays an extremely high H2 evolution rate of 8269.9μmol g−1 h−1,achieves an apparent quantum efficiency(AQE)of 3.24%,and also possesses outsatnding durability.Theoretical calculations further demonstrate that N and S dopants can not only introduce doping energy level to reduce the band gap,but also induce charge redistribution to facilitate hydrogen adsorption,thus promoting the photocatalytic HER process.Moreover,femtosecond transient absorption(fs-TA)spectroscopy further corroborates the efficient photogenerated carrier transport of N,S-g-C_(3)N_(4).This research highlights a promising and reliable strategy to achieve superior photocatalytic activity,and exhibits significant guidance for precise designing high-efficiency photocatalysts.展开更多
F-B co-doped TiO_(2)nanosheets with exposed anatase(001)facets were synthesized via a one-pot solvothermal method,and their photocatalytic hydrogen evolution performance was investigated.Characterization results confi...F-B co-doped TiO_(2)nanosheets with exposed anatase(001)facets were synthesized via a one-pot solvothermal method,and their photocatalytic hydrogen evolution performance was investigated.Characterization results confirm that this method effectively promotes the growth of the highly active anatase(001)facets and enhances visible and infrared light absorption while inducing oxygen vacancies.Under optimal conditions,the hydrogen evolution reaches 20.57μmol after 10 h of ultraviolet-visible(UV-Vis)light irradiation,exceeding the commercial TiO_(2)nanoparticles Degussa P25 by more than 10 times.These findings highlight the potential of F-B co-doped TiO_(2)nanosheets for efficient photocatalysis.展开更多
Sodium-ion batteries(SIBs)are emerging as a promising alternative for large-scale energy storage,particularly in grid applications.Within the array of potential cathode materials,Fe/Mn-based layered oxides are notable...Sodium-ion batteries(SIBs)are emerging as a promising alternative for large-scale energy storage,particularly in grid applications.Within the array of potential cathode materials,Fe/Mn-based layered oxides are notable for their advantageous theoretical specific capacity,economic viability,and environmental sustainability.Nevertheless,the practical application of Fe/Mn-based layered oxides is constrained by their suboptimal cycle performance and rate capability during actual charging and discharging.Ion doping is an effective approach for addressing the aforementioned issues.In this context,we have successfully developed a novel K^(+) and Mg^(2+) codoped P2-Na_(0.7)Fe_(0.5)Mn_(0.5)O_(2) cathode to address these challenges.By doping with 0.05 K^(+) and 0.2 Mg^(2+),the cathode demonstrated excellent cycling stability,retaining 95% of its capacity after 50 cycles at 0.2C,whereas the undoped material retained only 59.7%.Even within a wider voltage range,the co-doped cathode retained 88% of its capacity after 100 cycles at 1C.This work integrated Mg^(2+) to activate oxygen redox reactions in Fe/Mn-based layered cathodes,thereby promoting a reversible hybrid redox process involving both anions and cations.Building on the Mg doping,larger K^(+) ions were introduced into the edge-sharing Na^(+) sites,enhancing the material's cyclic stability and expanding the interplanar distance.The significant improvement of Na^(+) diffusion coefficient by K^(+)/Mg^(2+) co-doping has been further confirmed via the galvanostatic intermittent titration technique(GITT).The study emphasizes the importance of co-doping with different coordination environments in future material design,aiming to achieve high operating voltage and energy density.展开更多
Volatile Organic Compounds(VOCs)are highly harmful to human beings and other organisms,and thus the elimination of VOCs is extremely urgent.Here,La-Si co-doped TiO_(2)microsphere photocatalysts,which were prepared by ...Volatile Organic Compounds(VOCs)are highly harmful to human beings and other organisms,and thus the elimination of VOCs is extremely urgent.Here,La-Si co-doped TiO_(2)microsphere photocatalysts,which were prepared by a hydrothermal method,exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO_(2).The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers,as verified by the electrochemical results in combination with density functional theory calculations.In addition,the Si dopant changed the microstructure and surface acidity,while the addition of La promoted the separation efficiency of charge carriers.More interestingly,it was found that singlet oxygen was the key species in the activation of molecular dioxygen,and it played a pivotal role in the photocatalytic decomposition of formaldehyde.This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.展开更多
Micro-porous TiO2 coatings co-doped with Zn^2＋ and Ag nanoparticles were fabricated on Ti by microarc oxidation （MAO） for 0.5, 1.5, 2 and 4 min, respectively. The evolutions of morphology and phase component of the...Micro-porous TiO2 coatings co-doped with Zn^2＋ and Ag nanoparticles were fabricated on Ti by microarc oxidation （MAO） for 0.5, 1.5, 2 and 4 min, respectively. The evolutions of morphology and phase component of the coating as a function of processing time were investigated. The microstructure of the 2 min treated coating was further observed by transmission electron microscopy to explore the coating formation mechanism. The amounts of Ag and Zn released from the 2 min treated coating were measured and the antibacterial properties of the coatings against Staphylococcus aureus （S. aureus） were also investigated. The obtained results showed that with prolonged MAO time, the contents of Ag and Zn on the coating surfaces increased. All the coatings were micro-porous with pore diameters of 1 -4μm; however, some pores were blocked by deposits on the 4 min treated coating. The 2 rain treated coating was composed of amorphous TiO2, anatase, futile, ZnO, Zn2TiO4 and homogenously distributed Ag nanoparticles. After immersion, Zn^2＋, Ag^＋, Ti^2＋ and Ca^2＋ were released from the coating and with the immersion time prolonged, the accumulated concentrations of these ions increased. After immersion for 36 weeks, the accumulated Zn2. and Ag^＋ concentrations were 6.88 and 0.684 ppm, respectively, which are higher than the minimal inhibitory concentration but much lower than the cytotoxic concentration. Compared with polished Ti control, the coatings co-doped with Zn^2＋ and Ag nanoparticles significantly inhibited the ad- hesions of S. uureus and reduced the amounts of planktonic bacteria in culture medium, indicating that the Zn and Ag co-doped TiO2 could be a bio-adaptable coating for long-lasting anti-microbial performance.展开更多
Y and Eu co-doped nano-TiO2 photocatalysts were successfully prepared via a sol-gel method and characterized by X-ray diffraction（XRD）, transmission electron microscopy（TEM）, ultraviolet-visible spectrophotometry...Y and Eu co-doped nano-TiO2 photocatalysts were successfully prepared via a sol-gel method and characterized by X-ray diffraction（XRD）, transmission electron microscopy（TEM）, ultraviolet-visible spectrophotometry（UV-vis）, photoluminescence（PL） and Fourier transform infrared（FT-IR） spectra. Experimental results indicated that Y and Eu doping inhibited the growth of crystalline size and the transformation from anatase to rutile phase and had the function of reducing particle reunion. At the same time, co-doping could also enhance the absorption in visible region and then narrowed the band gap. The photocatalytic activities of the samples were evaluated by the degradation of methylene blue（MB） under ultraviolet（UV） light irradiation, which showed much enhanced photocatalytic activities over un-doped TiO2. The degradation rate of 1.5% Y/Eu-TiO2 of methylene blue was 86%, which was about 5 times of that of un-doped TiO2, and the possible reasons for the improvement of photocatalytic activities were analyzed. In this experiment, the dopant amount of rare earth was 1.5% and the ratio of Y：Eu was 2：3 for the maximum photocatalytic degradation, and the sample calcined at 500℃ showed the best reactivity. For the best samples above, the removal rate of phenol under visble light was 53% whthin 2 h.展开更多
A novel lanthanum and sulfur co-doped TiO2 photocatalyst was synthesized by precipitation-dipping method,and characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM)and UV-Vis diffuse reflectance ...A novel lanthanum and sulfur co-doped TiO2 photocatalyst was synthesized by precipitation-dipping method,and characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM)and UV-Vis diffuse reflectance spectroscopy.Compared with the S-doped TiO,La-doped TiO2 and the standard Degussa P25 photocatalysts,the lanthanum and sulfur co-doped TiO2 photocatalyst(the molar percentage of La is 3.0%)calcined at 450℃for 2 h showed the strongest absorption for visible light and highest activities for degradation of reactive blue 19 dye in aqueous solution under visible light(λ〉400 nm)irradiation.It was also discovered that the co-doping of lanthanum and sulfur hindered the aggregation and growth of TiO2 particles,and the doping of lanthanum reduced slightly the phase transition temperature ofTiO2 from anatase to rutile.展开更多
K−Na co-doped δ-MnO_(2)(KNMOH)nanoflowers were synthesized,and their cytotoxic effects against HeLa cervical cancer cells were evaluated.The KNMOH exhibited significant dose-and time-dependent cytotoxicity at concent...K−Na co-doped δ-MnO_(2)(KNMOH)nanoflowers were synthesized,and their cytotoxic effects against HeLa cervical cancer cells were evaluated.The KNMOH exhibited significant dose-and time-dependent cytotoxicity at concentrations of 50 and 100μg/mL.After 24 h of incubation treatment,cell viability decreased to(36.8±6.5)% and(33.4±6.4)%at 50 and 100μg/mL,respectively.With extended exposure to 48 h,cell viability was(45.2±2.3)%and(32.3±2.8)%at the same concentrations.Phase-contrast microscopy revealed characteristic morphological changes including cell shrinkage and membrane blebbing formation,indicative of cell death.These findings demonstrate the potential of KNMOH nanoflowers as a cytotoxic agent for cervical cancer applications and provide a foundation for further mechanistic studies.展开更多
Modulating the electronic structure of a photocatalyst and constructing spatially separated redox sites are key strategies for achieving the photocatalytic dual-channel generation of H_(2)O_(2).In this study,a graphen...Modulating the electronic structure of a photocatalyst and constructing spatially separated redox sites are key strategies for achieving the photocatalytic dual-channel generation of H_(2)O_(2).In this study,a graphene-modified non-compensated Cu/N-co-doped titanium dioxide(Cu-N-TiO_(2)/rGO)photocatalyst was designed for the efficient synthesis of H_(2)O_(2) via a dual-channel pathway.Precise modulation of the TiO_(2) conduction band position was achieved through the synergistic coupling of Cu 3d orbitals hybridized with Ti 3d orbitals and hybridization of N 2p orbitals with O 2p orbitals.This approach significantly improved the utilization of sunlight while satisfying the redox potential requirements.Cu doping not only promoted the formation of oxygen vacancies but also reduced the formation of Ti^(3+)ions,the photogenerated charge recombination centers.The non-compensated doping of N effectively increased the solubility of Cu^(2+)ions in the titanium dioxide lattice,enhanced the adsorption of hydroxyl radical intermediates,and created conditions for the subsequent hydroxyl radical combinations promoting the generation of H_(2)O_(2).In addition,the introduction of highly conductive graphene improved the interfacial carrier separation efficiency while realizing the spatial separation of redox sites,creating conditions for dual-channel reactions.The experimental results showed that the H_(2)O_(2) yield of Cu-N-TiO_(2)/rGO under simulated sunlight reached 1266.7μmol/L,which was 25.2 times higher than that of pristine TiO_(2).This study elucidated the synergistic mechanism of the energy band structure modulation and interfacial optimization,which provided a new idea for the design of dual-channel H_(2)O_(2) production photocatalysts.展开更多
In this paper,a visible light-responsive Sn^(2+)and N co-doped TiO_(2)photocatalyst was prepared by facile one-pot hydrothermal method.All as-prepared samples were characterized in detail by a series of characterizati...In this paper,a visible light-responsive Sn^(2+)and N co-doped TiO_(2)photocatalyst was prepared by facile one-pot hydrothermal method.All as-prepared samples were characterized in detail by a series of characterization approaches.The results showed that the Sn^(2+)and N elements were co-doped into TiO_(2),while the catalyst still maintains anatase crystal structure and gets irregular little nanocluster in diameter of 9–10 nm with higher specific surface area.The absorption edge of Sn^(2+)and N co-doped TiO_(2)extends to the visible light region.Compared with Sn^(2+)-doped TiO_(2)and N-TiO_(2),the absorption edges have obvious red-shift of about 50 and 70 nm,respectively.The synergistic effect of O 2p-N 2p and O 2p-Sn 5s hybridization to form impurity levels is the main reason for the red-shift.The hydrogen production performance of the Sn^(2+)and N co-doping TiO_(2)(n(N)/n(Ti)=1)catalyst reached the maximum value of 0.37 mmol·h^(-1)·g^(-1)under visible light,which is higher than that of N-doped TiO_(2)and SnTiO_(2)-doped TiO_(2)singly.This result is due to the wider visible light region-responsive ability of Sn^(2+)and N codoped into TiO_(2).Furthermore,mild hydrothermal methods will not make the Sn^(2+)oxidized to Sn^(4+),which make the catalysts still maintain high photocatalytic performance.This work provides a simple and mild method for the preparation of dual-element co-doped TiO_(2)with high crystallinity,excellent performance and broad application prospects.展开更多
Carbon-based adsorption and TiO_(2)-based photocatalysis are both safe and low-cost ways of pollutant pu-rification.Constructing C-TiO_(2)architectures can effectively improve removal efficiency.However,most of those ...Carbon-based adsorption and TiO_(2)-based photocatalysis are both safe and low-cost ways of pollutant pu-rification.Constructing C-TiO_(2)architectures can effectively improve removal efficiency.However,most of those carbon frames only acted as supporting substrates,exhibiting rather limited synergistic action from TiO_(2)and carbon.Herein,Fe/N co-doped nano-TiO_(2)wrapped on mesoporous carbon spheres with a core-shell structure was designed.The Fe,N co-doped carbon sphere with a hierarchical structure im-proved the synergy of adsorption and transfer during the photocatalytic process.Without extra dopant,the Fe and N partly exposed on the surface realized the in-situ migrating into the TiO_(2)shell to en-hance the interface effect,which significantly promoted the photocatalytic efficiency of the composite.Furthermore,the photocatalytic efficiency of the composite was investigated through two typical pollu-tants under visible-light irradiation.The degradation efficiencies for rhodamine B and paraxylene were 96.2%in 60 min and 94.1%in 20 min,respectively,with the apparent rate constant of 0.045 min^(-1)and 0.049 min^(-1),8.3 and 11.4 times of that for bare TiO_(2).The composite is likely advantageous for treating diverse environmental pollutants.展开更多
Enhancing catalytic efficiency and selectivity is critical issues for CO_(2) conversion.The rod-like Cu/N co-doped TiO_(2) samples(Cu/N-TiO_(2)) were synthesized by the electrospinning-calcination method.The substitut...Enhancing catalytic efficiency and selectivity is critical issues for CO_(2) conversion.The rod-like Cu/N co-doped TiO_(2) samples(Cu/N-TiO_(2)) were synthesized by the electrospinning-calcination method.The substitutional Cu and interstitial N doping not only enhanced visible-light absorption ability,but also formed the Ti(Ⅲ)sites.The obviously synergistic effect between the photocatalysis and thermalcatalysis appeared for CO_(2) conversion over the 8-Cu/N-TiO_(2) catalyst.After 9 h visible-light-illumination at 160℃,the CO,CH4and O_(2) yields reached 49.7,1455.1 and 2910.2μmol/gcat,respectively.In the 7thcycling,the yields of two main CH4and O_(2) products were slightly down by less than 11.5%,and the selectivity of CH_(4) product kept above 98%.Combined with the theoretical surface mode,Cu/N co-doping could promote the adsorption-ability for H_(2)O and CO_(2) molecules and reduce activation-energy for CO_(2)conversion.Hence,the co-doping construction showed a great significance of designing efficient photothermal catalysts for the CO_(2)conversion application.展开更多
Bacterial infection and related diseases are threatening the health of human beings.Photocatalytic disinfection as a simple and low-cost disinfection strategy is attracting more and more attention.In this work,TiO2 na...Bacterial infection and related diseases are threatening the health of human beings.Photocatalytic disinfection as a simple and low-cost disinfection strategy is attracting more and more attention.In this work,TiO2 nanoparticles(NPs)were modified by co-doping of Ce and Er using the sol-gel method,which endowed TiO2 NPs with enhanced visible light photocatalytic performance but not pure ultraviolet photocatalytic properties compared the untreated TiO2.Our results disclosed that as the doping content of Er increased,the photocatalytic activity of modified TiO2 NPs initially increased and subsequently decreased.The same trend occurred for Ce doping.When the doping dose of Er and Ce is 0.5 mol%and 0.2 mol%,the 0.5Ce0.2Ti-O calcined at 800℃ presented the best antibacterial properties,with the antibacterial efficiency of 91.23%and 92.8%for Staphylococcus aureus and Escherichia coli,respectively.The existence of Er ions is thought to successfully turn the near-infrared radiation into visible region,which is easier to be absorbed by TiO2 NPs.Meanwhile,the addition of Ce ions can effectively extend spectral response range and inhibit the recombination of electrons and holes,enhancing the photocatalytic disinfection activity of co-doped TiO2.展开更多
Lattice‐doping and surface decoration are prospective routes to improve the visible‐light photocatalytic ability of TiO2,but the two techniques are difficult to combine into one preparation process because they are ...Lattice‐doping and surface decoration are prospective routes to improve the visible‐light photocatalytic ability of TiO2,but the two techniques are difficult to combine into one preparation process because they are usually conducted under different conditions,which limits the efficiency of TiO2 modification.In this study,TiO2 was successfully modified by simultaneous lattice‐doping and surface decoration,and the visible‐light photocatalytic capacity was largely improved.Upon comparing the method reported here with previous ones,the most significant difference is that Fe(II)‐phenanthroline was first used as the co‐precursor of the introduced elements of C,N,and Fe.These three elements were simultaneously introduced to TiO2 at high levels by this co‐precursor method.The as‐synthesized photocatalysts were systemically investigated and analyzed by several characterization methods such as XRD,FT‐IR,XPS,Raman spectroscopy,EPR,UV‐Vis DRS,photoluminescence spectra,photocurrent,electrochemical impedance spectra,TEM,and HRTEM.The photocatalytic degradation of 4‐NP under visible‐light irradiation was used to evaluate the photocatalytic activity of the photocatalysts.Based on the experimental data,a probable mechanism for the photocatalytic degradation by the photocatalysts is proposed.This is a novel method of using one source to simultaneously introduce metal and non‐metal elements to TiO2 at high levels,which may provide a new way to prepare highly effective TiO2 photocatalysts.展开更多
Hollow nanostructures with external shells and inner voids have been proved to greatly shorten the transport distance of ions/electrons and buffer volume change,especially for the large-sized potassium-ions in seconda...Hollow nanostructures with external shells and inner voids have been proved to greatly shorten the transport distance of ions/electrons and buffer volume change,especially for the large-sized potassium-ions in secondary batteries.In this work,hollow carbon(HC) nanospheres embedded with S,P co-doped NiSe_(2)nanoparticles are fabricated by "drop and dry" and "dissolving and precipitation" processes to form Ni(OH)2nanocrystals followed by annealing with S and P dopants to form nanoparticles.The resultant S,P-NiSe_(2)/HC composite exhibits excellent cyclic performance with 131.6 mA h g^(-1)at1000 mA g^(-1)after 3000 cycles for K^(+)storage and a capacity of 417.1 mA h g^(-1)at 1000 mA g^(-1)after1000 cycles for Li^(+)storage.K-ion full cells are assembled and deliver superior cycling stability with a ca pacity of 72.5 mA h g^(-1)at 200 mA g^(-1)after 500 cycles.The hollow carbon shell with excellent electrical conductivity effectively promotes the transporta tion and tolerates large volume variation for both K^(+)and Li^(+).Density functional theory calculations confirm that the S and P co-doping NiSe_(2) enables stronger adsorption of K^(+)ions and higher electrical conductivity that contributes to the improved electrochemical performance.展开更多
Nitrogen(N)and phosphorus(P)co-doped anatase TiO_(2) nanosheets were realized by low-temperature self-doping N-TiO_(2) followed by high-temperature P doping with foreign precursor.It is found that P doping process can...Nitrogen(N)and phosphorus(P)co-doped anatase TiO_(2) nanosheets were realized by low-temperature self-doping N-TiO_(2) followed by high-temperature P doping with foreign precursor.It is found that P doping process can maintain good TiO_(2) nanosheets morphology with exposed{001}facets.Chemical state of dopants indicates that N and P atoms replace O on O sites in TiO_(2) lattice.Compared with pure TiO_(2) and N-doped TiO_(2),N-P codoped TiO_(2) nanosheets exhibits stronger optical absorption and higher degradation rate of dye molecules in visible light regime.The enhanced photocatalytic properties are attributed to two factors.On one hand,N-P co-doping can effectively reduce band gap of TiO_(2) from 3.20 to 2.48 eV,leading to an enhancement of the absorption in visible light regime.On the other hand,the presence of exposed{001}facets of TiO_(2) nanosheets can induce the effective sepa-ration of photogenerated electrons and holes in reaction.展开更多
Various compositions of cobalt and sulfur co-doped titania nano-photocatalyst are synthesized via sol–gel method. A number of techniques including X-ray diffraction（XRD）, ultraviolet–visible（UV–Vis）, Rutherford...Various compositions of cobalt and sulfur co-doped titania nano-photocatalyst are synthesized via sol–gel method. A number of techniques including X-ray diffraction（XRD）, ultraviolet–visible（UV–Vis）, Rutherford backscattering spectrometry（RBS）, thermal gravimetric analysis（TGA）Raman, N2 sorption, electron microscopy are used to examine composition, crystalline phase, morphology, distribution of dopants, surface area and optical properties o synthesized materials. The synthesized materials consisted of quasispherical nanoparticles of anatase phase exhibiting a high surface area and homogeneous distribution o dopants. Cobalt and sulfur co-doped titania demonstrated remarkable structural and optical properties leading to an efficient photocatalytic activity for degradation of dyes and phenol under visible light irradiations. Moreover, the effect of dye concentration catalyst dose and p H on photodegradation behavior of environmental pollutants and recyclability of the catalyst is also examined to optimize the activity of nano-photocatalys and gain a better understanding of the process.展开更多
基金the University Grants Commission (UGC) for providing BSR fellowship
文摘Undoped and Ni–S co-doped mesoporous TiO2 nano materials were synthesized by using sol–gel method.The characteristic features of as prepared catalyst samples were investigated using various advanced spectroscopic and analytical techniques.The characterization results of the samples revealed that all the samples exhibited anatase phase(XRD),decreasing band gap(2.68 eV)(UV–Vis-DRS),small particle size(9.2 nm)(TEM),high surface area(142.156 m^2·g^-1)(BET),particles with spherical shape and smooth morphology(SEM);there is a frequency shift observed for co-doped sample(FT-IR)and the elemental composition electronic states and position of the doped elements(Ni and S)in the TiO2 lattice analyzed by XPS and EDX.These results supported the photocatalytic degradation of Bismarck Brown Red(BBR)achieved with in 110 min and also exhibited the antibacterial activity on Staphylococcus aureus(MTCC-3160),Pseudomonas fluorescence(MTCC-1688)under visible light irradiation.
基金Project supported by the Natural Science Foundation of China(21407084,51474133)
文摘The existence form and effect of La on the phase composition,morphology,recombination of photocarriers,and optical absorptivity of La-F codoped TiO2 were investigated.Experimental results indicate that all the phase composition of samples is anatase TiO2,the grain sizes decrease with the increasing of La content The catalysts have a well-defined spherical structure with an average size of 12-14 nm,and the doping elements are uniformly dispersed.Compared with pure TiO2,the absorption edge of La1.5F5-TiO2 red shifts from 388 to 437 nm,accordingly the energy gap(Eg) reduces from 32 to 2.84 eV,Besides,the recombination rate of electron-holes in La1.5F5-TiO2 is the weakest among the prepared samples,and the specific surface area of La1.5F5-TiO2 reaches 105.27 m2/g.The apparent reaction rate constant k of La1.5F5-TiO2 for methylene blue(MB) degradation under visible light obtained from the apparent first-order model achieves 0.0166±0.52 min-1,which is greater than 0.0033±0.09 min 1 of TiO2.Moreover,high-resolution transmission electron microscopy(HRTEM) observation reveals that there coexist La2O3 particles in the co-doped TiO2.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.41373127） and Liaon- ing Provincial Natural Science Foundation of China （No.2013020121）.
文摘A series of Ce, H3PW12O40 co-doped TiO2 hollow fibers photocatalysts have been prepared by sol-gel method using ammonium ceric nitrate, H3PW12O40 and tetrabutyltitanate as precursors and cotton fibers as template, followed by calcination at 500 ℃ in N2 atmosphere for 2 h. Scanning electron microscopy, X-ray diffraction, nitrogen adsorption-desorption mea- surements, and UV-Vis spectroscopy are employed to characterize the morphology, crystal structure, surface structure, and optical absorption properties of the samples. The photo- catalytic performance of the samples has been studied by photodegradation phenol in water under UV and visible light irradiation. The results show that the TiO2 fiber materials have hollow structures, and the co-doped TiO2 hollow fibers exhibit higher photocatalytic activities for the degradation of phenol than un-doped, single-doped TiO2 hollow fibers under UV and visible light. In addition, the recyclability of co-doped TiO2 fibers is also confirmed that the TiO2 fiber retains ca. 90% of its activity after being used four times. It is shown that the co-doped TiO2 fibers can be activated by visible light and may be potentially applied to the treatment of water contaminated by organic pollutants. The synergistic effect of Ce and H3PW12O40 co-doping plays an important role in improving the photocatalytic activity.
基金supported by the National Natural Science Foun-dation of China(No.62004143)the Key R&D Program of Hubei Province(No.2022BAA084)the Natural Science Foundation of Hubei Province(No.2021CFB133).
文摘Doping engineering is an effective strategy for graphitic carbon nitride(g-C_(3)N_(4))to improve its photocat-alytic hydrogen evolution reaction(HER)performance.In this work,a novel nitrogen and sulfur co-doped g-C_(3)N_(4)(N,S-g-C_(3)N_(4))is elaborately designed on the basis of theoretical predictions of first-principle density functional theory(DFT).The calculated Gibbs free energy of adsorbed hydrogen(ΔGH∗)for N,S-g-C_(3)N_(4) at the N-doping active sites is extremely close to zero(0.01 eV).Inspired by the theoretical predictions,the N,S-g-C_(3)N_(4) is successfully fabricated through ammonia-rich pyrolysis synthesis strategy,in which ammonia is in-situ obtained by pyrolyzing melamine.Subsequent characterizations indicate that the N,S-g-C_(3)N_(4) possesses high specific surface area,outstanding light utilization,good hydrophilicity,and efficient carrier transfer efficiency.Consequently,the N,S-g-C_(3)N_(4) displays an extremely high H2 evolution rate of 8269.9μmol g−1 h−1,achieves an apparent quantum efficiency(AQE)of 3.24%,and also possesses outsatnding durability.Theoretical calculations further demonstrate that N and S dopants can not only introduce doping energy level to reduce the band gap,but also induce charge redistribution to facilitate hydrogen adsorption,thus promoting the photocatalytic HER process.Moreover,femtosecond transient absorption(fs-TA)spectroscopy further corroborates the efficient photogenerated carrier transport of N,S-g-C_(3)N_(4).This research highlights a promising and reliable strategy to achieve superior photocatalytic activity,and exhibits significant guidance for precise designing high-efficiency photocatalysts.
基金National Natural Science Foundation of China(No.81861138040)。
文摘F-B co-doped TiO_(2)nanosheets with exposed anatase(001)facets were synthesized via a one-pot solvothermal method,and their photocatalytic hydrogen evolution performance was investigated.Characterization results confirm that this method effectively promotes the growth of the highly active anatase(001)facets and enhances visible and infrared light absorption while inducing oxygen vacancies.Under optimal conditions,the hydrogen evolution reaches 20.57μmol after 10 h of ultraviolet-visible(UV-Vis)light irradiation,exceeding the commercial TiO_(2)nanoparticles Degussa P25 by more than 10 times.These findings highlight the potential of F-B co-doped TiO_(2)nanosheets for efficient photocatalysis.
基金financially supported by the National Natural Science Foundation of China(12175089,12205127,52220105010)the Key Research and Development Program of Yunnan Province(202103AF140006)+3 种基金the Applied Basic Research Programs of Yunnan Provincial Science and Technology Department(202001AW070004,202301AS070051,202301AU070064)Yunnan Industrial Innovative Talents Program for“Xingdian Talent Support Plan”(KKXY202252001)Yunnan Program for Introducing Foreign Talents(202305AO350042)Yunnan Major Scientific and Technological Projects(202202AG050003).
文摘Sodium-ion batteries(SIBs)are emerging as a promising alternative for large-scale energy storage,particularly in grid applications.Within the array of potential cathode materials,Fe/Mn-based layered oxides are notable for their advantageous theoretical specific capacity,economic viability,and environmental sustainability.Nevertheless,the practical application of Fe/Mn-based layered oxides is constrained by their suboptimal cycle performance and rate capability during actual charging and discharging.Ion doping is an effective approach for addressing the aforementioned issues.In this context,we have successfully developed a novel K^(+) and Mg^(2+) codoped P2-Na_(0.7)Fe_(0.5)Mn_(0.5)O_(2) cathode to address these challenges.By doping with 0.05 K^(+) and 0.2 Mg^(2+),the cathode demonstrated excellent cycling stability,retaining 95% of its capacity after 50 cycles at 0.2C,whereas the undoped material retained only 59.7%.Even within a wider voltage range,the co-doped cathode retained 88% of its capacity after 100 cycles at 1C.This work integrated Mg^(2+) to activate oxygen redox reactions in Fe/Mn-based layered cathodes,thereby promoting a reversible hybrid redox process involving both anions and cations.Building on the Mg doping,larger K^(+) ions were introduced into the edge-sharing Na^(+) sites,enhancing the material's cyclic stability and expanding the interplanar distance.The significant improvement of Na^(+) diffusion coefficient by K^(+)/Mg^(2+) co-doping has been further confirmed via the galvanostatic intermittent titration technique(GITT).The study emphasizes the importance of co-doping with different coordination environments in future material design,aiming to achieve high operating voltage and energy density.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.22076063,22076098,and 21477047)the Natural Science Foundation of Shandong Province(No.ZR2020MB033)+1 种基金the Key Laboratory of Photochemical Conversion and Optoelectronic Materials,TIPC,CAS(No.PCOM202106)the program for Taishan Scholars of Shandong Province,and the Science and Technology Programof the University of Jinan(No.XKY2111).
文摘Volatile Organic Compounds(VOCs)are highly harmful to human beings and other organisms,and thus the elimination of VOCs is extremely urgent.Here,La-Si co-doped TiO_(2)microsphere photocatalysts,which were prepared by a hydrothermal method,exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO_(2).The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers,as verified by the electrochemical results in combination with density functional theory calculations.In addition,the Si dopant changed the microstructure and surface acidity,while the addition of La promoted the separation efficiency of charge carriers.More interestingly,it was found that singlet oxygen was the key species in the activation of molecular dioxygen,and it played a pivotal role in the photocatalytic decomposition of formaldehyde.This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.
基金the financial support of the National Program on Key Basic Research Project of China ("973 Program", Grant No. 2012CB619103)the National Natural Science Foundation of China (Grant Nos. 51201129, 51371137, 51571158)+2 种基金the Natural Science Foundation of Shanxi Province (Grant No. 2015JQ5130)the Open Research Fund of State Key Laboratory of BioelectronicsSoutheast University and the Fundamental Research Funds for the Central Universities
文摘Micro-porous TiO2 coatings co-doped with Zn^2＋ and Ag nanoparticles were fabricated on Ti by microarc oxidation （MAO） for 0.5, 1.5, 2 and 4 min, respectively. The evolutions of morphology and phase component of the coating as a function of processing time were investigated. The microstructure of the 2 min treated coating was further observed by transmission electron microscopy to explore the coating formation mechanism. The amounts of Ag and Zn released from the 2 min treated coating were measured and the antibacterial properties of the coatings against Staphylococcus aureus （S. aureus） were also investigated. The obtained results showed that with prolonged MAO time, the contents of Ag and Zn on the coating surfaces increased. All the coatings were micro-porous with pore diameters of 1 -4μm; however, some pores were blocked by deposits on the 4 min treated coating. The 2 rain treated coating was composed of amorphous TiO2, anatase, futile, ZnO, Zn2TiO4 and homogenously distributed Ag nanoparticles. After immersion, Zn^2＋, Ag^＋, Ti^2＋ and Ca^2＋ were released from the coating and with the immersion time prolonged, the accumulated concentrations of these ions increased. After immersion for 36 weeks, the accumulated Zn2. and Ag^＋ concentrations were 6.88 and 0.684 ppm, respectively, which are higher than the minimal inhibitory concentration but much lower than the cytotoxic concentration. Compared with polished Ti control, the coatings co-doped with Zn^2＋ and Ag nanoparticles significantly inhibited the ad- hesions of S. uureus and reduced the amounts of planktonic bacteria in culture medium, indicating that the Zn and Ag co-doped TiO2 could be a bio-adaptable coating for long-lasting anti-microbial performance.
基金Project supported by National Natural Science Foundation of China(51174020)
文摘Y and Eu co-doped nano-TiO2 photocatalysts were successfully prepared via a sol-gel method and characterized by X-ray diffraction（XRD）, transmission electron microscopy（TEM）, ultraviolet-visible spectrophotometry（UV-vis）, photoluminescence（PL） and Fourier transform infrared（FT-IR） spectra. Experimental results indicated that Y and Eu doping inhibited the growth of crystalline size and the transformation from anatase to rutile phase and had the function of reducing particle reunion. At the same time, co-doping could also enhance the absorption in visible region and then narrowed the band gap. The photocatalytic activities of the samples were evaluated by the degradation of methylene blue（MB） under ultraviolet（UV） light irradiation, which showed much enhanced photocatalytic activities over un-doped TiO2. The degradation rate of 1.5% Y/Eu-TiO2 of methylene blue was 86%, which was about 5 times of that of un-doped TiO2, and the possible reasons for the improvement of photocatalytic activities were analyzed. In this experiment, the dopant amount of rare earth was 1.5% and the ratio of Y：Eu was 2：3 for the maximum photocatalytic degradation, and the sample calcined at 500℃ showed the best reactivity. For the best samples above, the removal rate of phenol under visble light was 53% whthin 2 h.
基金the National Natural Science Foundation of China(No.20677008)the Innovation Foundation of Donghua University for Doctors
文摘A novel lanthanum and sulfur co-doped TiO2 photocatalyst was synthesized by precipitation-dipping method,and characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM)and UV-Vis diffuse reflectance spectroscopy.Compared with the S-doped TiO,La-doped TiO2 and the standard Degussa P25 photocatalysts,the lanthanum and sulfur co-doped TiO2 photocatalyst(the molar percentage of La is 3.0%)calcined at 450℃for 2 h showed the strongest absorption for visible light and highest activities for degradation of reactive blue 19 dye in aqueous solution under visible light(λ〉400 nm)irradiation.It was also discovered that the co-doping of lanthanum and sulfur hindered the aggregation and growth of TiO2 particles,and the doping of lanthanum reduced slightly the phase transition temperature ofTiO2 from anatase to rutile.
文摘K−Na co-doped δ-MnO_(2)(KNMOH)nanoflowers were synthesized,and their cytotoxic effects against HeLa cervical cancer cells were evaluated.The KNMOH exhibited significant dose-and time-dependent cytotoxicity at concentrations of 50 and 100μg/mL.After 24 h of incubation treatment,cell viability decreased to(36.8±6.5)% and(33.4±6.4)%at 50 and 100μg/mL,respectively.With extended exposure to 48 h,cell viability was(45.2±2.3)%and(32.3±2.8)%at the same concentrations.Phase-contrast microscopy revealed characteristic morphological changes including cell shrinkage and membrane blebbing formation,indicative of cell death.These findings demonstrate the potential of KNMOH nanoflowers as a cytotoxic agent for cervical cancer applications and provide a foundation for further mechanistic studies.
文摘Modulating the electronic structure of a photocatalyst and constructing spatially separated redox sites are key strategies for achieving the photocatalytic dual-channel generation of H_(2)O_(2).In this study,a graphene-modified non-compensated Cu/N-co-doped titanium dioxide(Cu-N-TiO_(2)/rGO)photocatalyst was designed for the efficient synthesis of H_(2)O_(2) via a dual-channel pathway.Precise modulation of the TiO_(2) conduction band position was achieved through the synergistic coupling of Cu 3d orbitals hybridized with Ti 3d orbitals and hybridization of N 2p orbitals with O 2p orbitals.This approach significantly improved the utilization of sunlight while satisfying the redox potential requirements.Cu doping not only promoted the formation of oxygen vacancies but also reduced the formation of Ti^(3+)ions,the photogenerated charge recombination centers.The non-compensated doping of N effectively increased the solubility of Cu^(2+)ions in the titanium dioxide lattice,enhanced the adsorption of hydroxyl radical intermediates,and created conditions for the subsequent hydroxyl radical combinations promoting the generation of H_(2)O_(2).In addition,the introduction of highly conductive graphene improved the interfacial carrier separation efficiency while realizing the spatial separation of redox sites,creating conditions for dual-channel reactions.The experimental results showed that the H_(2)O_(2) yield of Cu-N-TiO_(2)/rGO under simulated sunlight reached 1266.7μmol/L,which was 25.2 times higher than that of pristine TiO_(2).This study elucidated the synergistic mechanism of the energy band structure modulation and interfacial optimization,which provided a new idea for the design of dual-channel H_(2)O_(2) production photocatalysts.
基金This study was financially supported by the Natural Science Foundation of China(No.21663009)the National Key R&D Projects of China(No.2018YFC1801706-01)the Science and Technology Supporting Project of Guizhou Province(Nos.[2019]2835 and[2021]480).
文摘In this paper,a visible light-responsive Sn^(2+)and N co-doped TiO_(2)photocatalyst was prepared by facile one-pot hydrothermal method.All as-prepared samples were characterized in detail by a series of characterization approaches.The results showed that the Sn^(2+)and N elements were co-doped into TiO_(2),while the catalyst still maintains anatase crystal structure and gets irregular little nanocluster in diameter of 9–10 nm with higher specific surface area.The absorption edge of Sn^(2+)and N co-doped TiO_(2)extends to the visible light region.Compared with Sn^(2+)-doped TiO_(2)and N-TiO_(2),the absorption edges have obvious red-shift of about 50 and 70 nm,respectively.The synergistic effect of O 2p-N 2p and O 2p-Sn 5s hybridization to form impurity levels is the main reason for the red-shift.The hydrogen production performance of the Sn^(2+)and N co-doping TiO_(2)(n(N)/n(Ti)=1)catalyst reached the maximum value of 0.37 mmol·h^(-1)·g^(-1)under visible light,which is higher than that of N-doped TiO_(2)and SnTiO_(2)-doped TiO_(2)singly.This result is due to the wider visible light region-responsive ability of Sn^(2+)and N codoped into TiO_(2).Furthermore,mild hydrothermal methods will not make the Sn^(2+)oxidized to Sn^(4+),which make the catalysts still maintain high photocatalytic performance.This work provides a simple and mild method for the preparation of dual-element co-doped TiO_(2)with high crystallinity,excellent performance and broad application prospects.
基金The work was supported by the National Natural Science Foun-dation of China(No.21974057).
文摘Carbon-based adsorption and TiO_(2)-based photocatalysis are both safe and low-cost ways of pollutant pu-rification.Constructing C-TiO_(2)architectures can effectively improve removal efficiency.However,most of those carbon frames only acted as supporting substrates,exhibiting rather limited synergistic action from TiO_(2)and carbon.Herein,Fe/N co-doped nano-TiO_(2)wrapped on mesoporous carbon spheres with a core-shell structure was designed.The Fe,N co-doped carbon sphere with a hierarchical structure im-proved the synergy of adsorption and transfer during the photocatalytic process.Without extra dopant,the Fe and N partly exposed on the surface realized the in-situ migrating into the TiO_(2)shell to en-hance the interface effect,which significantly promoted the photocatalytic efficiency of the composite.Furthermore,the photocatalytic efficiency of the composite was investigated through two typical pollu-tants under visible-light irradiation.The degradation efficiencies for rhodamine B and paraxylene were 96.2%in 60 min and 94.1%in 20 min,respectively,with the apparent rate constant of 0.045 min^(-1)and 0.049 min^(-1),8.3 and 11.4 times of that for bare TiO_(2).The composite is likely advantageous for treating diverse environmental pollutants.
基金National Natural Science Foundation of China(No.51802082)Key Scientific and Technological Project of Henan Province(No.222102320100)Program for Science&Technology Innovation Talents in Universities of Henan Province(No.21HATIT016).
文摘Enhancing catalytic efficiency and selectivity is critical issues for CO_(2) conversion.The rod-like Cu/N co-doped TiO_(2) samples(Cu/N-TiO_(2)) were synthesized by the electrospinning-calcination method.The substitutional Cu and interstitial N doping not only enhanced visible-light absorption ability,but also formed the Ti(Ⅲ)sites.The obviously synergistic effect between the photocatalysis and thermalcatalysis appeared for CO_(2) conversion over the 8-Cu/N-TiO_(2) catalyst.After 9 h visible-light-illumination at 160℃,the CO,CH4and O_(2) yields reached 49.7,1455.1 and 2910.2μmol/gcat,respectively.In the 7thcycling,the yields of two main CH4and O_(2) products were slightly down by less than 11.5%,and the selectivity of CH_(4) product kept above 98%.Combined with the theoretical surface mode,Cu/N co-doping could promote the adsorption-ability for H_(2)O and CO_(2) molecules and reduce activation-energy for CO_(2)conversion.Hence,the co-doping construction showed a great significance of designing efficient photothermal catalysts for the CO_(2)conversion application.
基金supported by the National Science Fund for Distinguished Young Scholars 51925104National Natural Science Foundation of China nos.51871162,51671081+2 种基金Natural Science Fund of Hubei Province,2018CFA064,RGC/NSFC(N_HKU725-1616)Hong Kong ITC(ITS/287/17,GHX/002/14SZ)as Health and Medical Research Fund(No.03142446).
文摘Bacterial infection and related diseases are threatening the health of human beings.Photocatalytic disinfection as a simple and low-cost disinfection strategy is attracting more and more attention.In this work,TiO2 nanoparticles(NPs)were modified by co-doping of Ce and Er using the sol-gel method,which endowed TiO2 NPs with enhanced visible light photocatalytic performance but not pure ultraviolet photocatalytic properties compared the untreated TiO2.Our results disclosed that as the doping content of Er increased,the photocatalytic activity of modified TiO2 NPs initially increased and subsequently decreased.The same trend occurred for Ce doping.When the doping dose of Er and Ce is 0.5 mol%and 0.2 mol%,the 0.5Ce0.2Ti-O calcined at 800℃ presented the best antibacterial properties,with the antibacterial efficiency of 91.23%and 92.8%for Staphylococcus aureus and Escherichia coli,respectively.The existence of Er ions is thought to successfully turn the near-infrared radiation into visible region,which is easier to be absorbed by TiO2 NPs.Meanwhile,the addition of Ce ions can effectively extend spectral response range and inhibit the recombination of electrons and holes,enhancing the photocatalytic disinfection activity of co-doped TiO2.
基金supported by the National Natural Science Foundation of China(51368044,51568051,51668046)the National Science Fund for Excellent Young Scholars(51422807)+6 种基金the Science and Technology Supporting Program of Jiangxi Province(20151BBG70018)the Natural Science Foundation of Jiangxi Province for Distinguished Young Scholars(20162BCB23041)the Science Foundation for Young Scientists of Jiangxi Province-Key Project(20171ACB21034)the Science and Technology Project of Jiangxi Provincial Education Department(GJJ160700)the Natural Science Foundation of Jiangxi Province(20161BAB216102)the Jiangxi Province Educational Reform Project(JXJG-16-8-7)the Nanchang Hangkong University Educational Reform Project(JY1604,JY1605,KCPY-1511)~~
文摘Lattice‐doping and surface decoration are prospective routes to improve the visible‐light photocatalytic ability of TiO2,but the two techniques are difficult to combine into one preparation process because they are usually conducted under different conditions,which limits the efficiency of TiO2 modification.In this study,TiO2 was successfully modified by simultaneous lattice‐doping and surface decoration,and the visible‐light photocatalytic capacity was largely improved.Upon comparing the method reported here with previous ones,the most significant difference is that Fe(II)‐phenanthroline was first used as the co‐precursor of the introduced elements of C,N,and Fe.These three elements were simultaneously introduced to TiO2 at high levels by this co‐precursor method.The as‐synthesized photocatalysts were systemically investigated and analyzed by several characterization methods such as XRD,FT‐IR,XPS,Raman spectroscopy,EPR,UV‐Vis DRS,photoluminescence spectra,photocurrent,electrochemical impedance spectra,TEM,and HRTEM.The photocatalytic degradation of 4‐NP under visible‐light irradiation was used to evaluate the photocatalytic activity of the photocatalysts.Based on the experimental data,a probable mechanism for the photocatalytic degradation by the photocatalysts is proposed.This is a novel method of using one source to simultaneously introduce metal and non‐metal elements to TiO2 at high levels,which may provide a new way to prepare highly effective TiO2 photocatalysts.
基金financially supported by the Shenzhen Science and Technology Program(JCYJ20220530141012028),ChinaThe National Natural Science Foundation of China(22005178),China+2 种基金The Key Research and Development Program of Shandong Province(2021ZLGX01),ChianThe fellowship of China Postdoctoral Science Foundation(2022M722333),Chianthe Jiangsu Funding Program for Excellent Postdoctoral Talent,Chian。
文摘Hollow nanostructures with external shells and inner voids have been proved to greatly shorten the transport distance of ions/electrons and buffer volume change,especially for the large-sized potassium-ions in secondary batteries.In this work,hollow carbon(HC) nanospheres embedded with S,P co-doped NiSe_(2)nanoparticles are fabricated by "drop and dry" and "dissolving and precipitation" processes to form Ni(OH)2nanocrystals followed by annealing with S and P dopants to form nanoparticles.The resultant S,P-NiSe_(2)/HC composite exhibits excellent cyclic performance with 131.6 mA h g^(-1)at1000 mA g^(-1)after 3000 cycles for K^(+)storage and a capacity of 417.1 mA h g^(-1)at 1000 mA g^(-1)after1000 cycles for Li^(+)storage.K-ion full cells are assembled and deliver superior cycling stability with a ca pacity of 72.5 mA h g^(-1)at 200 mA g^(-1)after 500 cycles.The hollow carbon shell with excellent electrical conductivity effectively promotes the transporta tion and tolerates large volume variation for both K^(+)and Li^(+).Density functional theory calculations confirm that the S and P co-doping NiSe_(2) enables stronger adsorption of K^(+)ions and higher electrical conductivity that contributes to the improved electrochemical performance.
基金financially supported by the National Natural Science Foundation of China(Nos.61434002,51571135)National Science Foundation of United States(Nos.DMR-1104994,CBET-1510121)+2 种基金Shanxi Scholars Program(No.[2012]12)"One Hundred Talented People"of Shanxi ProvinceShanxi Province Foundations(Nos.[2012]10,[2013]9)
文摘Nitrogen(N)and phosphorus(P)co-doped anatase TiO_(2) nanosheets were realized by low-temperature self-doping N-TiO_(2) followed by high-temperature P doping with foreign precursor.It is found that P doping process can maintain good TiO_(2) nanosheets morphology with exposed{001}facets.Chemical state of dopants indicates that N and P atoms replace O on O sites in TiO_(2) lattice.Compared with pure TiO_(2) and N-doped TiO_(2),N-P codoped TiO_(2) nanosheets exhibits stronger optical absorption and higher degradation rate of dye molecules in visible light regime.The enhanced photocatalytic properties are attributed to two factors.On one hand,N-P co-doping can effectively reduce band gap of TiO_(2) from 3.20 to 2.48 eV,leading to an enhancement of the absorption in visible light regime.On the other hand,the presence of exposed{001}facets of TiO_(2) nanosheets can induce the effective sepa-ration of photogenerated electrons and holes in reaction.
文摘Various compositions of cobalt and sulfur co-doped titania nano-photocatalyst are synthesized via sol–gel method. A number of techniques including X-ray diffraction（XRD）, ultraviolet–visible（UV–Vis）, Rutherford backscattering spectrometry（RBS）, thermal gravimetric analysis（TGA）Raman, N2 sorption, electron microscopy are used to examine composition, crystalline phase, morphology, distribution of dopants, surface area and optical properties o synthesized materials. The synthesized materials consisted of quasispherical nanoparticles of anatase phase exhibiting a high surface area and homogeneous distribution o dopants. Cobalt and sulfur co-doped titania demonstrated remarkable structural and optical properties leading to an efficient photocatalytic activity for degradation of dyes and phenol under visible light irradiations. Moreover, the effect of dye concentration catalyst dose and p H on photodegradation behavior of environmental pollutants and recyclability of the catalyst is also examined to optimize the activity of nano-photocatalys and gain a better understanding of the process.
