Developing heterojunction photocatalyst with well-matched interfaces andmultiple charge transfer paths is vital to boost carrier separation efficiency for photocatalytic antibiotics removal,but still remains a great c...Developing heterojunction photocatalyst with well-matched interfaces andmultiple charge transfer paths is vital to boost carrier separation efficiency for photocatalytic antibiotics removal,but still remains a great challenge.In present work,a new strategy of chloride anion intercalation in Bi_(2)O_(3)via one-pot hydrothermal process is proposed.The as-prepared Ta-BiOCl/Bi_(24)O_(31)Cl_(10)(TBB)heterojunctions are featured with Ta-Bi_(24)O_(31)Cl_(10)and Ta-BiOCl lined shoulder-by-shouleder via semi-coherent interfaces.In this TBB heterojunctions,the well-matched semi-coherent interfaces and shoulder-by-shoulder structures provide fast electron transfer andmultiple transfer paths,respectively,leading to enhanced visible light response and improved photogenerated charge separation.Meanwhile,a type-II heterojunction for photocharge separation has been obtained,in which photogenerated electrons are drove from the CB(conduction band)of Ta-Bi_(24)O_(31)Cl_(10)to the both of bilateral empty CB of Ta-BiOCl and gathered on the CB of Ta-BiOCl,while the photogenerated holes are left on the VB(valence band)of Ta-Bi_(24)O_(31)Cl_(10),effectively hindering the recombination of photogenerated electron-hole pairs.Furthermore,the separated electrons can effectively activate dissolved oxygen for the generation of reactive oxygen species(·O_(2)^(−)).Such TBB heterojunctions exhibit remarkably superior photocatalytic degradation activity for tetracycline hydrochloride(TCH)solution to Bi_(2)O_(3),Ta-BiOCl and Ta-Bi_(24)O_(31)Cl_(10).This work not only proposes a Ta-BiOCl/Bi_(24)O_(31)Cl_(10)shoulder-by-shoulder micro-ribbon architectures with semi-coherent interfaces and successive type-Ⅱheterojunction for highly efficient photocatalytic activity,but offers a new insight into the design of highly efficient heterojunction through phasestructure synergistic transformation strategy.展开更多
Bismuth oxide/titania, one interfacial composite semiconductor with high photocatalytic activity under solar light, was prepared at low temperature. The structure was characterized by X-ray diffractometry （XRD）, sca...Bismuth oxide/titania, one interfacial composite semiconductor with high photocatalytic activity under solar light, was prepared at low temperature. The structure was characterized by X-ray diffractometry （XRD）, scanning electron microscopy （SEM）, brunauer-emmett-teller （BET）, X-ray photoelectron spectroscopy （XPS） and diffuse reflection spectra （DRS）. The results indicate that deposited titania nanoparticles on bismuth oxide surface have micro-nano structure, and this composite material exhibits porosity and increased surface hydroxyl groups. Furthermore, the as-prepared photocatalyst shows higher photocatalytic activity to the degradation of 4-chlorophenol than pure titania or P25 under sunlight.展开更多
In order to solve the problems of environment pollution and high cost in traditional process of bismuth subcarbonate preparation, a new process using ball-milling transformation method from NH4HCO3 and Bi2O3 was propo...In order to solve the problems of environment pollution and high cost in traditional process of bismuth subcarbonate preparation, a new process using ball-milling transformation method from NH4HCO3 and Bi2O3 was proposed. Additionally, the kinetics of bismuth subcarbonate preparation was studied. Effects of reaction temperature, particle size of bismuth oxide, solid-to-liquid ratio and concentrations of ammonium bicarbonate on the conversion rate of bismuth oxide were studied. The results indicate that the conversion rate of bismuth oxide significantly increased under the conditions of higher temperature, smaller particle size, higher concentration of ammonium bicarbonate and smaller solid-to-liquid ratio. The XRD and ICP-AES analyses show that the purity of product is high. The reaction kinetics with activation energy of 9.783 kJ/mol was analyzed by shrinking core model, and the whole transformation process is controlled by solid product layer diffusion. A semi-empirical kinetics equation was obtained to describe the conversion process.展开更多
Oxygen vacancies(Vo)in electrocatalysts are closely correlated with the hydrogen evo-lution reaction(HER)activity.The role of vacancy defects and the effect of their concentration,how-ever,yet remains unclear.Herein,B...Oxygen vacancies(Vo)in electrocatalysts are closely correlated with the hydrogen evo-lution reaction(HER)activity.The role of vacancy defects and the effect of their concentration,how-ever,yet remains unclear.Herein,Bi2O3,an unfavorable electrocata-lyst for the HER due to a less than ideal hydrogen adsorption Gibbs free energy(ΔGH*),is utilized as a perfect model to explore the func-tion of Vo on HER performance.Through a facile plasma irradia-tion strategy,Bi2O3 nanosheets with different Vo concentrations are fabricated to evaluate the influence of defects on the HER process.Unexpectedly,while the generated oxygen vacancies contribute to the enhanced HER performance,higher Vo concentrations beyond a saturation value result in a significant drop in HER activity.By tunning the Vo concentration in the Bi_(2)O_(3)nanosheets via adjusting the treatment time,the Bi2O3 catalyst with an optimized oxygen vacancy concentration and detectable charge carrier concentration of 1.52×10^(24)cm^(−3)demonstrates enhanced HER performance with an overpotential of 174.2 mV to reach 10 mA cm^(−2),a Tafel slope of 80 mV dec−1,and an exchange current density of 316 mA cm−2 in an alkaline solution,which approaches the top-tier activity among Bi-based HER electrocatalysts.Density-functional theory calculations confirm the preferred adsorption of H*onto Bi2O3 as a function of oxygen chemical potential(ΔμO)and oxygen partial potential(PO2)and reveal that high Vo concentrations result in excessive stability of adsorbed hydrogen and hence the inferior HER activity.This study reveals the oxygen vacancy concentration-HER catalytic activity relationship and provides insights into activating catalytically inert materials into highly efficient electrocatalysts.展开更多
Access to safe drinking water free from microbial pollution is an issue of global concern. The use of photocatalytic thin films in water treatment has focused on titanium dioxide, which requires UV-activation, proving...Access to safe drinking water free from microbial pollution is an issue of global concern. The use of photocatalytic thin films in water treatment has focused on titanium dioxide, which requires UV-activation, proving a potential barrier to upscaling and implementation in the real world. Visible-light-activated photocatalytic thin films, such as bismuth oxide, have recently been shown to have antimicrobial properties. However, more understanding of the photocatalytic effect on the microbial population in water is required. Glass beads coated with bismuth oxide were incubated with either Microcystis aeruginosa, Anabaena sp. or free-floating genomic DNA. The presence of bismuth oxide-coated glass beads was able to rapidly stop a population of cyanobacteria from increasing. The coated beads were also able to degrade genomic DNA. Leachate from the beads showed no increase in toxicity against human liver cells. This data demonstrates the efficacy of bismuth oxide-coated glass beads for controlling potentially dangerous cyanobacterial populations, whilst potentially reducing the amount of free-floating genomic DNA(an essential issue in the face of antimicrobial resistance) – all of which should be essential considerations in emerging water treatment technologies.展开更多
Two series of cobalt(Ⅲ)\|containing spinel catalysts were prepared by the decomposition of the corresponding nitrates. The catalysts doped with bismuth oxide exhibit a higher activity in the wet air oxidation of acet...Two series of cobalt(Ⅲ)\|containing spinel catalysts were prepared by the decomposition of the corresponding nitrates. The catalysts doped with bismuth oxide exhibit a higher activity in the wet air oxidation of acetic acid than those without dopant bismuth oxide. The catalysts were investigated by XRD,TEM,ESR,UV\|DRS and XPS,and the interaction between Co and Bi was studied as well. It has been found that nano\|sized bismuth oxide is paved on the surface of cobalt spinel crystal and the structures of cobalt(Ⅲ)\|containing spinel are still maintained. The shift of the binding energy of Bi\-\{\%4f\%\-\{7/2\}\} is related to the catalytic activity of these catalysts doped with bismuth oxide.展开更多
Since low overpotential for the anodic ethanol oxidation reaction(EOR)can favor the higher output voltage and power of direct ethanol fuel cells(DEFCs),it is critical to design new EOR catalysts with efficient ethanol...Since low overpotential for the anodic ethanol oxidation reaction(EOR)can favor the higher output voltage and power of direct ethanol fuel cells(DEFCs),it is critical to design new EOR catalysts with efficient ethanol-to-CO_(2)activity at low applied potentials.Thereby,carbon-supported Ir-Bi_(2)O_(3)(Ir-Bi_(2)O_(3)/C)catalysts with highly dispersive bismuth oxide on the iridium surface are designed and prepared,which can merit splitting the ethanol C–C bond and promoting the oxidation of C1 intermediates at the bifunctional interfaces.The as-obtained Ir-Bi2O3/C catalysts show superior EOR mass activity of up to ca.2250 m A mgIr-1.Moreover,they exhibit the record lowest onset oxidation potentials(0.17–0.22 V vs.RHE)and the peak potential(ca.0.58 V vs.RHE),being 130–300 m V lower than the previous landmark noble metallic catalysts.Furthermore,an apparent C1 pathway faraday efficiency(FEC1)of 28%±5.9%at 0.5 V vs.RHE can be obtained at Ir-Bi_(2)O_(3)/C.This work might provide new insights into the new anodic EOR catalysts for increasing the power of DEFCs.展开更多
Reduction smelting of the bismuth oxide residue from pressure leaching of bismuth sulfide was investigated in the FeO-SiO_2-CaO ternary slag system.The results show that all the recovery ratios of Bi,Ag,Cu and Pb incr...Reduction smelting of the bismuth oxide residue from pressure leaching of bismuth sulfide was investigated in the FeO-SiO_2-CaO ternary slag system.The results show that all the recovery ratios of Bi,Ag,Cu and Pb increase with the increase of reductive coal proportion,reaction temperature and time,while too much reductive coal would help Fe enter metal phase;CaO/SiO_2and Fe O/SiO_2 of the chosen slag system should be 0.5-0.75 and 1.25-1.75,respectively,for the reason that the slag system has the optimum mobility and is beneficial for the recovery of metals.The corresponding optimum conditions are determined as follows:the added coal proportion is 7%of the leaching residue,CaO/SiO_2 mass ratio in the chosen slag system is 0.5 and FeO-SiO_2 is 1.5,the reaction temperature is 1300°C and the reaction time is 40 min.Under the above conditions,the recovery ratios of Bi,Ag,Cu and Pb are 99.6%,99.8%,97.0%and 97.3%,respectively.展开更多
Novel environmentally friendly inorganic red pigments based on calcium bismuth oxide Ca3(Bi1-xREx)8O15(0≤x≤0.09;RE=Sc^(3+),Er^(3+),Y^(3+),Ho^(3+)and Dy^(3+)),were successfully synthesized and the color properties we...Novel environmentally friendly inorganic red pigments based on calcium bismuth oxide Ca3(Bi1-xREx)8O15(0≤x≤0.09;RE=Sc^(3+),Er^(3+),Y^(3+),Ho^(3+)and Dy^(3+)),were successfully synthesized and the color properties were characterized.The color of these pigments depended on the composition and the synthesis condition,and the most vivid red color was obtained for the Ca3(Bi0.93Y0.07)8O15 sample calcined thrice at 800℃for 2 h.The L*and a*values corresponding to brightness and red chromaticity for this pigment were 45.6 and+30.6,respectively,which were greater than those of a commercially available Fe2O3 pigment(L^(*)=38.4,a^(*)=+29.5).Since the present pigment is composed of nontoxic and safe elements,it should be an attractive alternative to the conventional Fe2O3 pigment.展开更多
Supported metal(oxide)clusters,with both rich surface sites and high atom utilization efficiency,have shown improved activity and selectivity for many catalytic reactions over nanoparticle and single atom catalysts.Ye...Supported metal(oxide)clusters,with both rich surface sites and high atom utilization efficiency,have shown improved activity and selectivity for many catalytic reactions over nanoparticle and single atom catalysts.Yet,the role of cluster catalysts has been rarely reported in CO_(2)electroreduction reaction(CO_(2)RR),which is a promising route for converting CO_(2)to liquid fuels like formic acid with renewable electricity.Here we develop a bismuth oxide(BiOn)cluster catalyst for highly efficient CO_(2)RR to formate.The BiOn cluster catalyst exhibits excellent activity,selectivity,and stability towards formate production,with a formate Faradaic efficiency of over 90%at a current density up to 500 mA·cm^(−2)in an alkaline membrane electrode assembly electrolyzer,corresponding to a mass activity as high as 3,750 A·gBi−1.The electrolyzer with the BiOn cluster catalyst delivers a remarkable formate production rate of 0.56 mmol·min−1 at a high single-pass CO_(2)conversion of 44%.Density functional theory calculations indicate that Bi4O_(3)cluster is more favorable for stabilizing the HCOO^(*)intermediate than Bi(001)surface and single site BiC_(4)motif,rationalizing the improved formate production over the BiOn cluster catalyst.This work highlights the great importance of cluster catalysts in activity and selectivity control in electrocatalytic CO_(2)conversion.展开更多
A homogeneous layer of Bi_2O_3-Bi_(14)WO_(24) composite(BWO/Bi_2O_3) thin film was fabricated using a combination of electrodeposition and thermal treatment. The evenly distributed Bi14 WO24 component within the Bi_2O...A homogeneous layer of Bi_2O_3-Bi_(14)WO_(24) composite(BWO/Bi_2O_3) thin film was fabricated using a combination of electrodeposition and thermal treatment. The evenly distributed Bi14 WO24 component within the Bi_2O_3 layer was found to be important in stabilising the photoelectrochemical performances of Bi_2O_3 photoanode by promoting the photoelectron transport. The unmodified Bi_2O_3 suffered from severe photocorrosion as proven by X-ray diffraction(XRD) and inductively coupled plasma(ICP) analyses while the composite thin film was active without noticeable activity decay for at least 3 h of illumination. This strategy might be applicable to other photocatalysts with stability issues.展开更多
The photocatalytic degradation on the bismuth containing complex oxide was revised in detail including the synthesis and classification of photocatalyts, and then the photocatalytic reaction, scavenger, and the mechan...The photocatalytic degradation on the bismuth containing complex oxide was revised in detail including the synthesis and classification of photocatalyts, and then the photocatalytic reaction, scavenger, and the mechanism of reaction. In particular, the perspectives of photocatalytic degradation on the bismuth containing oxide were analyzed in detail.展开更多
The advancement in catalysis techniques for sustainable environmental applications,particularly an alternative to the current Haber-Bosch process for NH_(3),has recently gained widespread attention.Although photocatal...The advancement in catalysis techniques for sustainable environmental applications,particularly an alternative to the current Haber-Bosch process for NH_(3),has recently gained widespread attention.Although photocatalytic conversion of N_(2) to NH_(3) using solar energy is an eco-friendly method,it has the limitation of low quantum yield.Recently,2D Bi-based photocatalysts which exhibit higher visible light absorption than TiO_(2) and higher stability than MXene have been an active research topic,and their performance can be enhanced through improved visible light absorption properties by incorporating plasmonic gold nanoparticles while nitrogen adsorption could be enhanced through oxygen vacancy(OV)processes.In the present study,we explore the application of 2D nanosized Bi_(2)O_(3–x) and gold nanoparticles for visible light photo generation of NH_(3).HRTEM and XPS reveal that the formation of AuNP and nano-sized Bi_(2)O_(3–x) in AuNP/Bi_(2)O_(3–x) heterozygote structure promotes the charge carrier mobility and charge transport at the interface,resulting in a 2.6-fold increase in the photocatalytic activity compared to micro-sized Bi_(2)O_(3–x) with AuNP.The improved photocatalytic performance can be ascribed to significant enhancement of visible light absorption by plasmonic nanoparticles,fast charge transport and mobility(due to sheet morphology)and the N_(2) activation by OV in AuNP/Bi_(2)O_(3–x) heterozygote.Through a systematic experimental investigation involving catalysts,concentration,pH,and scavengers,the highest photocatalytic performance was achieved with the heterozygote structures of AuNP/n-Bi_(2)O_(3–x) under optimized conditions,yielding 432.5μmol gcat^(-1) h^(-1) of NH_(3).展开更多
Composites consisting of strontium stabilized bismuth oxide （Bi1.14Sr0.43O2.14, SSB） and silver were investigated as cathodes for intermediate-temperature solid oxide fuel cells with doped ceria electrolyte. There w...Composites consisting of strontium stabilized bismuth oxide （Bi1.14Sr0.43O2.14, SSB） and silver were investigated as cathodes for intermediate-temperature solid oxide fuel cells with doped ceria electrolyte. There were no chemical reactions between the two components. The microstructure of the interfaces between composite cathodes and Ce0.8Sm0.2O1.9 （SDC） electrolytes was examined by scanning electron microscopy （SEM）. Impedance spectroscopy measurements show that the performance of cathode fired at 700 ℃ is the best. When the content of Ag2O is 70 wt%, polarization resistance values for the SSB-Ag cathodes are as low as 0.2 Ωcm^2 at 700℃ and 0.29 Ωcm^2 at 650℃. These results are much smaller than some of other reported composite cathodes on doped ceria electrolyte and indicate that SSB-Ag composite is a potential cathode material for intermediate temperature SOFCs.展开更多
Electrocatalytic carbon dioxide reduction reaction(eCO_(2)RR)represents one of the most promising technologies for sustainable conversion of CO_(2) to value-added products.Although metal-organic frameworks(MOFs)can be...Electrocatalytic carbon dioxide reduction reaction(eCO_(2)RR)represents one of the most promising technologies for sustainable conversion of CO_(2) to value-added products.Although metal-organic frameworks(MOFs)can be vastly functionalized to create active sites for CO_(2)RR,low intrinsic electrical conductivity always makes MOFs unfavorable candidates for eCO_(2)RR.Besides,studies on how to regulate eCO_(2)RR activity of MOFs from linkers'functionalities viewpoint lag far behind when compared with the assembly of multinuclear metal-centered clusters.In this work,non-toxic bismuth(Ⅲ)oxide(Bi2O3)was incorporated into a series of two-dimensional(2D)MOFs(ZrLX)established from Zr-oxo clusters and triazine-centered 3-c linkers with different functionalities(LX=1-5)to give composites ZrLX/Bi2O3.To investigate how functionalities on linkers distantly tune the eCO_(2)RR performance of MOFs,electron-donating/withdrawing groups were installed at triazine core or benzoate terminals.It is found that ZrL2/Bi2O3(-F functionalized on triazine core)exhibits the best eCO_(2)RR performance with the highest Faradaic efficiency(FE)of 96.73%at-1.07 V vs.RHE,the largest electroactive surface(Cdi=4.23 mF cm-2)and the highest electrical conductivity(5.54 x 10-7 S cm-1),highlighting tuning linker functionalities and hence electronic structure as an alternative way to regulate eCO_(2)RR.展开更多
Engineering point defects such as metal and oxygen vacancies play a crucial role in manipulating the electrical,optical,and catalytic properties of oxide semiconductors for solar water splitting.Herein,we synthesized ...Engineering point defects such as metal and oxygen vacancies play a crucial role in manipulating the electrical,optical,and catalytic properties of oxide semiconductors for solar water splitting.Herein,we synthesized nanoporous CuBi_(2)O_(4)(np-CBO)photocathodes and engineered their surface point defects via rapid thermal processing(RTP)in controlled atmospheres(O_(2),N_(2),and vacuum).We found that the O_(2)-RTP treatment of np-CBO increased the charge carrier density effectively without hampering the nanoporous morphology,which was attributed to the formation of copper vacancies(VCu).Further analyses revealed that the amounts of oxygen vacancies(Vo)and Cu^(1+)were reduced simultaneously,and the relative electrochemical active surface area increased after the O_(2)-RTP treatment.Notably,the point defects(VC_(u),Cu^(1+),and Vo)regulated np-CBO achieved a superb water-splitting photocurrent density of-1.81 m A cm^(-2) under simulated sunlight illumination,which is attributed to the enhanced charge transport and transfer properties resulting from the regulated surface point defects.Finally,the reversibility of the formation of the point defects was checked by sequential RTP treatments(O_(2)-N_(2)-O_(2)-N_(2)),demonstrating the strong dependence of photocurrent response on the RTP cycles.Conclusively,the surface point defect engineering via RTP treatment in a controlled atmosphere is a rapid and facile strategy to promote charge transport and transfer properties of photoelectrodes for efficient solar water-splitting.展开更多
Aqueous battery-supercapacitor hybrid devices(BSHs)are of great importance to enrich electrochemical energy storage systems with both high energy and power densities.However,further improvement of BSHs in aqueous elec...Aqueous battery-supercapacitor hybrid devices(BSHs)are of great importance to enrich electrochemical energy storage systems with both high energy and power densities.However,further improvement of BSHs in aqueous electrolytes is greatly hampered by operating voltage and capacity limits.Different from the conventional intercalation/de-intercalation mechanism,Bi_(2)O_(3) implements charge storage by a reversible phase conversion mechanism.Herein,taking Bi_(2)O_(3) electrode with wide potential window(from-1.2 to 1 V vs.saturated calomel electrode)and high capacity as battery-type anode,we propose that the overall performance of aqueous BSHs can be greatly upgraded under neutral condition.By paring with stable layer-structuredδ-MnO_(2) cathode,a sodium-ion Bi_(2)O_(3)//MnO_(2) BSH with an ultrahigh voltage of 2.4 V in neutral sodium sulfate electrolyte is developed for the first time.This hybrid device exhibits high capacity(~215 C g^(-1) at 1 mA cm^(-2)),relatively long lifespan(~77.2%capacity retention after 1500 cycles),remarkable energy density(71.7 Wh kg^(-1)@400.5 W kg^(-1))and power density(3204.3 W kg^(-1)@18.8 Wh kg^(-1)).Electrochemical measurements combining a set of spectroscopic techniques reveal the reversible phase conversion between bismuth oxide and metallic bismuth(Bi_(2)O_(3)?Bi0)through Bi^(2+) transition phase in neutral sodium sulfate solution,which can deliver multielectron transfer up to 6,leading to the high-energy BSHs.Our work sheds light on the feasibility of using Bi_(2)O_(3) electrode under neutral condition to address the issue of narrow voltage and low capacity for aqueous BSHs.展开更多
Photoelectrochemical reduction of CO_(2)to produce CO with metal-organic frameworks(MOFs)is recognized as a desirable technology to mitigate CO_(2)emission and generate sustainable energy.To achieve highly efficient e...Photoelectrochemical reduction of CO_(2)to produce CO with metal-organic frameworks(MOFs)is recognized as a desirable technology to mitigate CO_(2)emission and generate sustainable energy.To achieve highly efficient electrocatalyst,it is essential to design a new material interface and uncover new reaction mechanisms or kinetics.Herein,we developed two metal-organic Cu-MOF and Bi-MOF layers using benzene tricarboxylic acid(H_(3)BTC)ligands on CuBi_(2)O_(4) photocathodes.Both MOF layers drastically improved the photoelectrochemical stability by suppressing the photo-corrosion through conformal surface passivation.The Cu-MOF modified CuBi_(2)O_(4) showed more significant charge separation and transfer efficiencies than the Bi-MOF modified control.Based on the transient photocurrent curves under the applied potential of 0.6 V vs.RHE,the rate-law analysis showed the CO_(2)photoreduction took place through a first-order reaction.Further,the photoelectrochemical impedance spectra(PEIS)revealed this reaction order,representing an“operando”analysis.Moreover,the reaction rate constant on Cu-MOF modified sample was higher than that on Bi-MOF modified one and bare CuBi_(2)O_(4).Combined with the density functional theory calculation,the surface absorption of CO_(2)and CO molecules and the higher energy barrier for*COOH intermediates could significantly determine the first order reaction.展开更多
Core-shell Bi-Bi2 O3/CNT(carbon nanotube) with 3-dimensional neural network structure where Bi-Bi2O3 nanospheres act as cell bodies supported by a 3-dimensional network of CNTs acting as synapses is designed and prepa...Core-shell Bi-Bi2 O3/CNT(carbon nanotube) with 3-dimensional neural network structure where Bi-Bi2O3 nanospheres act as cell bodies supported by a 3-dimensional network of CNTs acting as synapses is designed and prepared by simple solvothermal method and subsequent annealing autoreduction treatment,and this structure facilitates the efficient transport of electrons.It can provide two electron transfer paths due to the double contact of Bi2O3 shell with CNT and metal Bi core which enhances the efficiency of the electrochemical reaction.The Bi-Bi2 O3/CNT electrode shows a high gravimetric capacitance of 850 F g-1(1 A g-1),and the specific capacitance of Bi-Bi2O3/CNT can be still 714 F g-1 at 30 A g-1 indicating excellent rate performance.The asymmetric supercapacitor is assembled with Bi-Bi2 O3/CNT as the negative electrode and Ni(OH)2/CNT as the positive electrode,delivering a high energy density of 36.7 Wh kg-1 and a maximum power density of 8000 W kg-1.Therefore,the core-shell Bi-Bi2O3/CNT with 3-dimensional neural network structure as the negative electrode of supercapacitor shows great potential in the field of energy storage in the future.展开更多
A series of bismuth borate silica glasses were prepared and their densities, linear refractive indices and transmission spectra were measured. The optical gaps Eopt were obtained from the extrapolation of the linear p...A series of bismuth borate silica glasses were prepared and their densities, linear refractive indices and transmission spectra were measured. The optical gaps Eopt were obtained from the extrapolation of the linear portions to zero absorption. A decrease in the value of Eopt with increasing bismuth content may be explained by suggesting that the non-bridging oxygen ion content increases .It was found that high refractive index and narrow bandgap could lead into high third-order optical nonlinearity.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22208262,52271228,52202298,52201279,51834009,and 51801151)the Natural Science Foundation of Shaanxi Province(Nos.2021JQ-468,2020JZ-47)+3 种基金the Natural Science Foundation of Shaanxi Provincial Department of Education(No.21JP086)the Postdoctoral Research Foundation of China(Nos.2020M683528 and 2018M633643XB)the Young Talent Fund of Association for Science and Technology in Shaanxi,China(No.20230625)the Hundred Talent Program of Shaanxi Province.
文摘Developing heterojunction photocatalyst with well-matched interfaces andmultiple charge transfer paths is vital to boost carrier separation efficiency for photocatalytic antibiotics removal,but still remains a great challenge.In present work,a new strategy of chloride anion intercalation in Bi_(2)O_(3)via one-pot hydrothermal process is proposed.The as-prepared Ta-BiOCl/Bi_(24)O_(31)Cl_(10)(TBB)heterojunctions are featured with Ta-Bi_(24)O_(31)Cl_(10)and Ta-BiOCl lined shoulder-by-shouleder via semi-coherent interfaces.In this TBB heterojunctions,the well-matched semi-coherent interfaces and shoulder-by-shoulder structures provide fast electron transfer andmultiple transfer paths,respectively,leading to enhanced visible light response and improved photogenerated charge separation.Meanwhile,a type-II heterojunction for photocharge separation has been obtained,in which photogenerated electrons are drove from the CB(conduction band)of Ta-Bi_(24)O_(31)Cl_(10)to the both of bilateral empty CB of Ta-BiOCl and gathered on the CB of Ta-BiOCl,while the photogenerated holes are left on the VB(valence band)of Ta-Bi_(24)O_(31)Cl_(10),effectively hindering the recombination of photogenerated electron-hole pairs.Furthermore,the separated electrons can effectively activate dissolved oxygen for the generation of reactive oxygen species(·O_(2)^(−)).Such TBB heterojunctions exhibit remarkably superior photocatalytic degradation activity for tetracycline hydrochloride(TCH)solution to Bi_(2)O_(3),Ta-BiOCl and Ta-Bi_(24)O_(31)Cl_(10).This work not only proposes a Ta-BiOCl/Bi_(24)O_(31)Cl_(10)shoulder-by-shoulder micro-ribbon architectures with semi-coherent interfaces and successive type-Ⅱheterojunction for highly efficient photocatalytic activity,but offers a new insight into the design of highly efficient heterojunction through phasestructure synergistic transformation strategy.
基金Project supported by the Scientific Research Foundation of Nanjing University of Information Science and Technology, ChinaProject (2010490511) supported by the Open Foundation of State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, China
文摘Bismuth oxide/titania, one interfacial composite semiconductor with high photocatalytic activity under solar light, was prepared at low temperature. The structure was characterized by X-ray diffractometry （XRD）, scanning electron microscopy （SEM）, brunauer-emmett-teller （BET）, X-ray photoelectron spectroscopy （XPS） and diffuse reflection spectra （DRS）. The results indicate that deposited titania nanoparticles on bismuth oxide surface have micro-nano structure, and this composite material exhibits porosity and increased surface hydroxyl groups. Furthermore, the as-prepared photocatalyst shows higher photocatalytic activity to the degradation of 4-chlorophenol than pure titania or P25 under sunlight.
基金Project(50774099)supported by the National Natural Science Foundation of China
文摘In order to solve the problems of environment pollution and high cost in traditional process of bismuth subcarbonate preparation, a new process using ball-milling transformation method from NH4HCO3 and Bi2O3 was proposed. Additionally, the kinetics of bismuth subcarbonate preparation was studied. Effects of reaction temperature, particle size of bismuth oxide, solid-to-liquid ratio and concentrations of ammonium bicarbonate on the conversion rate of bismuth oxide were studied. The results indicate that the conversion rate of bismuth oxide significantly increased under the conditions of higher temperature, smaller particle size, higher concentration of ammonium bicarbonate and smaller solid-to-liquid ratio. The XRD and ICP-AES analyses show that the purity of product is high. The reaction kinetics with activation energy of 9.783 kJ/mol was analyzed by shrinking core model, and the whole transformation process is controlled by solid product layer diffusion. A semi-empirical kinetics equation was obtained to describe the conversion process.
基金This work was financially supported by the Australian Research Council(ARC)through Future Fellowship grants(FT180100387 and FT160100281)Discovery Projects(DP200103568,DP210100472,and DP200102546)+1 种基金WL thanks the support of the Science and Technology Commission of Shanghai Municipality(19520713200)Open access funding provided by Shanghai Jiao Tong University
文摘Oxygen vacancies(Vo)in electrocatalysts are closely correlated with the hydrogen evo-lution reaction(HER)activity.The role of vacancy defects and the effect of their concentration,how-ever,yet remains unclear.Herein,Bi2O3,an unfavorable electrocata-lyst for the HER due to a less than ideal hydrogen adsorption Gibbs free energy(ΔGH*),is utilized as a perfect model to explore the func-tion of Vo on HER performance.Through a facile plasma irradia-tion strategy,Bi2O3 nanosheets with different Vo concentrations are fabricated to evaluate the influence of defects on the HER process.Unexpectedly,while the generated oxygen vacancies contribute to the enhanced HER performance,higher Vo concentrations beyond a saturation value result in a significant drop in HER activity.By tunning the Vo concentration in the Bi_(2)O_(3)nanosheets via adjusting the treatment time,the Bi2O3 catalyst with an optimized oxygen vacancy concentration and detectable charge carrier concentration of 1.52×10^(24)cm^(−3)demonstrates enhanced HER performance with an overpotential of 174.2 mV to reach 10 mA cm^(−2),a Tafel slope of 80 mV dec−1,and an exchange current density of 316 mA cm−2 in an alkaline solution,which approaches the top-tier activity among Bi-based HER electrocatalysts.Density-functional theory calculations confirm the preferred adsorption of H*onto Bi2O3 as a function of oxygen chemical potential(ΔμO)and oxygen partial potential(PO2)and reveal that high Vo concentrations result in excessive stability of adsorbed hydrogen and hence the inferior HER activity.This study reveals the oxygen vacancy concentration-HER catalytic activity relationship and provides insights into activating catalytically inert materials into highly efficient electrocatalysts.
文摘Access to safe drinking water free from microbial pollution is an issue of global concern. The use of photocatalytic thin films in water treatment has focused on titanium dioxide, which requires UV-activation, proving a potential barrier to upscaling and implementation in the real world. Visible-light-activated photocatalytic thin films, such as bismuth oxide, have recently been shown to have antimicrobial properties. However, more understanding of the photocatalytic effect on the microbial population in water is required. Glass beads coated with bismuth oxide were incubated with either Microcystis aeruginosa, Anabaena sp. or free-floating genomic DNA. The presence of bismuth oxide-coated glass beads was able to rapidly stop a population of cyanobacteria from increasing. The coated beads were also able to degrade genomic DNA. Leachate from the beads showed no increase in toxicity against human liver cells. This data demonstrates the efficacy of bismuth oxide-coated glass beads for controlling potentially dangerous cyanobacterial populations, whilst potentially reducing the amount of free-floating genomic DNA(an essential issue in the face of antimicrobial resistance) – all of which should be essential considerations in emerging water treatment technologies.
文摘Two series of cobalt(Ⅲ)\|containing spinel catalysts were prepared by the decomposition of the corresponding nitrates. The catalysts doped with bismuth oxide exhibit a higher activity in the wet air oxidation of acetic acid than those without dopant bismuth oxide. The catalysts were investigated by XRD,TEM,ESR,UV\|DRS and XPS,and the interaction between Co and Bi was studied as well. It has been found that nano\|sized bismuth oxide is paved on the surface of cobalt spinel crystal and the structures of cobalt(Ⅲ)\|containing spinel are still maintained. The shift of the binding energy of Bi\-\{\%4f\%\-\{7/2\}\} is related to the catalytic activity of these catalysts doped with bismuth oxide.
基金supported by the National Natural Science Foundation of China(NSFC,22172121)the Natural Science Foundation of Sichuan Province(NSFSC,2023NSFSC1076)+1 种基金the Young Talent Project of State Ethnic Affairs Commissionthe Fundamental Research Funds for the Central Universities(ZYN2023106),Southwest Minzu University。
文摘Since low overpotential for the anodic ethanol oxidation reaction(EOR)can favor the higher output voltage and power of direct ethanol fuel cells(DEFCs),it is critical to design new EOR catalysts with efficient ethanol-to-CO_(2)activity at low applied potentials.Thereby,carbon-supported Ir-Bi_(2)O_(3)(Ir-Bi_(2)O_(3)/C)catalysts with highly dispersive bismuth oxide on the iridium surface are designed and prepared,which can merit splitting the ethanol C–C bond and promoting the oxidation of C1 intermediates at the bifunctional interfaces.The as-obtained Ir-Bi2O3/C catalysts show superior EOR mass activity of up to ca.2250 m A mgIr-1.Moreover,they exhibit the record lowest onset oxidation potentials(0.17–0.22 V vs.RHE)and the peak potential(ca.0.58 V vs.RHE),being 130–300 m V lower than the previous landmark noble metallic catalysts.Furthermore,an apparent C1 pathway faraday efficiency(FEC1)of 28%±5.9%at 0.5 V vs.RHE can be obtained at Ir-Bi_(2)O_(3)/C.This work might provide new insights into the new anodic EOR catalysts for increasing the power of DEFCs.
基金Project(134414) supported by the Postdoctoral Funded Program of Central South University,China
文摘Reduction smelting of the bismuth oxide residue from pressure leaching of bismuth sulfide was investigated in the FeO-SiO_2-CaO ternary slag system.The results show that all the recovery ratios of Bi,Ag,Cu and Pb increase with the increase of reductive coal proportion,reaction temperature and time,while too much reductive coal would help Fe enter metal phase;CaO/SiO_2and Fe O/SiO_2 of the chosen slag system should be 0.5-0.75 and 1.25-1.75,respectively,for the reason that the slag system has the optimum mobility and is beneficial for the recovery of metals.The corresponding optimum conditions are determined as follows:the added coal proportion is 7%of the leaching residue,CaO/SiO_2 mass ratio in the chosen slag system is 0.5 and FeO-SiO_2 is 1.5,the reaction temperature is 1300°C and the reaction time is 40 min.Under the above conditions,the recovery ratios of Bi,Ag,Cu and Pb are 99.6%,99.8%,97.0%and 97.3%,respectively.
基金supported by the Development of Alternative Technology for Hazardous Chemical SubstancesDevelopment of Novel Environment-and Human-friendly Inorganic Pigments for Three Primary Colors(FY2010-2014)programs of the New Energy+1 种基金Industrial Technology Development Organization(NEDO)the Ministry of Economy,Trade and Industry,Japan(METI).
文摘Novel environmentally friendly inorganic red pigments based on calcium bismuth oxide Ca3(Bi1-xREx)8O15(0≤x≤0.09;RE=Sc^(3+),Er^(3+),Y^(3+),Ho^(3+)and Dy^(3+)),were successfully synthesized and the color properties were characterized.The color of these pigments depended on the composition and the synthesis condition,and the most vivid red color was obtained for the Ca3(Bi0.93Y0.07)8O15 sample calcined thrice at 800℃for 2 h.The L*and a*values corresponding to brightness and red chromaticity for this pigment were 45.6 and+30.6,respectively,which were greater than those of a commercially available Fe2O3 pigment(L^(*)=38.4,a^(*)=+29.5).Since the present pigment is composed of nontoxic and safe elements,it should be an attractive alternative to the conventional Fe2O3 pigment.
基金the National Key Research and Development Program of China(No.2021YFA1501503),the National Natural Science Foundation of China(Nos.22002121,22172121,and 22002155)the Open Project Fund of State Key Laboratory of Catalysis(No.N-19-04)+2 种基金the Fundamental Research Funds for the Central Universities(No.2021HQZZ05),the Key Laboratory of Fundamental Chemistry of the State Ethnic Commission(No.2021PTJS25)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA21061010),the Natural Science Foundation of Liaoning Province(No.2021-MS-022)the High-Level Talents Innovation Project of Dalian City(No.2020RQ038).
文摘Supported metal(oxide)clusters,with both rich surface sites and high atom utilization efficiency,have shown improved activity and selectivity for many catalytic reactions over nanoparticle and single atom catalysts.Yet,the role of cluster catalysts has been rarely reported in CO_(2)electroreduction reaction(CO_(2)RR),which is a promising route for converting CO_(2)to liquid fuels like formic acid with renewable electricity.Here we develop a bismuth oxide(BiOn)cluster catalyst for highly efficient CO_(2)RR to formate.The BiOn cluster catalyst exhibits excellent activity,selectivity,and stability towards formate production,with a formate Faradaic efficiency of over 90%at a current density up to 500 mA·cm^(−2)in an alkaline membrane electrode assembly electrolyzer,corresponding to a mass activity as high as 3,750 A·gBi−1.The electrolyzer with the BiOn cluster catalyst delivers a remarkable formate production rate of 0.56 mmol·min−1 at a high single-pass CO_(2)conversion of 44%.Density functional theory calculations indicate that Bi4O_(3)cluster is more favorable for stabilizing the HCOO^(*)intermediate than Bi(001)surface and single site BiC_(4)motif,rationalizing the improved formate production over the BiOn cluster catalyst.This work highlights the great importance of cluster catalysts in activity and selectivity control in electrocatalytic CO_(2)conversion.
基金supported by the Australian Research Council under the Laureate Fellowship Scheme(FL140100081)
文摘A homogeneous layer of Bi_2O_3-Bi_(14)WO_(24) composite(BWO/Bi_2O_3) thin film was fabricated using a combination of electrodeposition and thermal treatment. The evenly distributed Bi14 WO24 component within the Bi_2O_3 layer was found to be important in stabilising the photoelectrochemical performances of Bi_2O_3 photoanode by promoting the photoelectron transport. The unmodified Bi_2O_3 suffered from severe photocorrosion as proven by X-ray diffraction(XRD) and inductively coupled plasma(ICP) analyses while the composite thin film was active without noticeable activity decay for at least 3 h of illumination. This strategy might be applicable to other photocatalysts with stability issues.
基金Supported by the Self-raised Project for the Basic Research for Application of Yunnan Province(2013FZ109)the Follow-up Project of Qujing Normal University for the National Natural Science Foundation(2106512005)+1 种基金the Innovation and Entrepreneurship Project for College Students of Qujing Normal Universitythe Project for Innovation Team of the Applied Chemical Material Preparation of Qujing Normal University(2106531001)
文摘The photocatalytic degradation on the bismuth containing complex oxide was revised in detail including the synthesis and classification of photocatalyts, and then the photocatalytic reaction, scavenger, and the mechanism of reaction. In particular, the perspectives of photocatalytic degradation on the bismuth containing oxide were analyzed in detail.
基金Financial support for this work by the National Research Foundation of Korea(2022R1F1A1074682,2022R1A4A1031687)Korea University,and the KU-KIST Research Fund.
文摘The advancement in catalysis techniques for sustainable environmental applications,particularly an alternative to the current Haber-Bosch process for NH_(3),has recently gained widespread attention.Although photocatalytic conversion of N_(2) to NH_(3) using solar energy is an eco-friendly method,it has the limitation of low quantum yield.Recently,2D Bi-based photocatalysts which exhibit higher visible light absorption than TiO_(2) and higher stability than MXene have been an active research topic,and their performance can be enhanced through improved visible light absorption properties by incorporating plasmonic gold nanoparticles while nitrogen adsorption could be enhanced through oxygen vacancy(OV)processes.In the present study,we explore the application of 2D nanosized Bi_(2)O_(3–x) and gold nanoparticles for visible light photo generation of NH_(3).HRTEM and XPS reveal that the formation of AuNP and nano-sized Bi_(2)O_(3–x) in AuNP/Bi_(2)O_(3–x) heterozygote structure promotes the charge carrier mobility and charge transport at the interface,resulting in a 2.6-fold increase in the photocatalytic activity compared to micro-sized Bi_(2)O_(3–x) with AuNP.The improved photocatalytic performance can be ascribed to significant enhancement of visible light absorption by plasmonic nanoparticles,fast charge transport and mobility(due to sheet morphology)and the N_(2) activation by OV in AuNP/Bi_(2)O_(3–x) heterozygote.Through a systematic experimental investigation involving catalysts,concentration,pH,and scavengers,the highest photocatalytic performance was achieved with the heterozygote structures of AuNP/n-Bi_(2)O_(3–x) under optimized conditions,yielding 432.5μmol gcat^(-1) h^(-1) of NH_(3).
基金Funded by the National Natural Science Foundation of China(No.20576063)the 973 Project of Ministry of Science and Technology in China(No.T2000026410)
文摘Composites consisting of strontium stabilized bismuth oxide （Bi1.14Sr0.43O2.14, SSB） and silver were investigated as cathodes for intermediate-temperature solid oxide fuel cells with doped ceria electrolyte. There were no chemical reactions between the two components. The microstructure of the interfaces between composite cathodes and Ce0.8Sm0.2O1.9 （SDC） electrolytes was examined by scanning electron microscopy （SEM）. Impedance spectroscopy measurements show that the performance of cathode fired at 700 ℃ is the best. When the content of Ag2O is 70 wt%, polarization resistance values for the SSB-Ag cathodes are as low as 0.2 Ωcm^2 at 700℃ and 0.29 Ωcm^2 at 650℃. These results are much smaller than some of other reported composite cathodes on doped ceria electrolyte and indicate that SSB-Ag composite is a potential cathode material for intermediate temperature SOFCs.
基金supported by the National Natural Science Foundation of China(22371054,22301045)the Foundation of Basic and Applied Basic Research of Guangdong Province(2020B1515120024,2024A1515012801)+1 种基金Science and Technology Planning Project of Guangdong Province(2021A0505030066,2023A0505050164)Science and Technology Program of Guangzhou(202201010244).
文摘Electrocatalytic carbon dioxide reduction reaction(eCO_(2)RR)represents one of the most promising technologies for sustainable conversion of CO_(2) to value-added products.Although metal-organic frameworks(MOFs)can be vastly functionalized to create active sites for CO_(2)RR,low intrinsic electrical conductivity always makes MOFs unfavorable candidates for eCO_(2)RR.Besides,studies on how to regulate eCO_(2)RR activity of MOFs from linkers'functionalities viewpoint lag far behind when compared with the assembly of multinuclear metal-centered clusters.In this work,non-toxic bismuth(Ⅲ)oxide(Bi2O3)was incorporated into a series of two-dimensional(2D)MOFs(ZrLX)established from Zr-oxo clusters and triazine-centered 3-c linkers with different functionalities(LX=1-5)to give composites ZrLX/Bi2O3.To investigate how functionalities on linkers distantly tune the eCO_(2)RR performance of MOFs,electron-donating/withdrawing groups were installed at triazine core or benzoate terminals.It is found that ZrL2/Bi2O3(-F functionalized on triazine core)exhibits the best eCO_(2)RR performance with the highest Faradaic efficiency(FE)of 96.73%at-1.07 V vs.RHE,the largest electroactive surface(Cdi=4.23 mF cm-2)and the highest electrical conductivity(5.54 x 10-7 S cm-1),highlighting tuning linker functionalities and hence electronic structure as an alternative way to regulate eCO_(2)RR.
基金supported by the Basic Science Research Program through the National Research Foundation of Korea,funded by the Ministry of Science,ICT,and Future Planning(NRF Award No.NRF-2019R1A2C2002024 and 2021R1A4A1031357)supported by the Basic Science Research Program through NRF funded by the Ministry of Education(NRF Award No.NRF2020R1A6A1A03043435)。
文摘Engineering point defects such as metal and oxygen vacancies play a crucial role in manipulating the electrical,optical,and catalytic properties of oxide semiconductors for solar water splitting.Herein,we synthesized nanoporous CuBi_(2)O_(4)(np-CBO)photocathodes and engineered their surface point defects via rapid thermal processing(RTP)in controlled atmospheres(O_(2),N_(2),and vacuum).We found that the O_(2)-RTP treatment of np-CBO increased the charge carrier density effectively without hampering the nanoporous morphology,which was attributed to the formation of copper vacancies(VCu).Further analyses revealed that the amounts of oxygen vacancies(Vo)and Cu^(1+)were reduced simultaneously,and the relative electrochemical active surface area increased after the O_(2)-RTP treatment.Notably,the point defects(VC_(u),Cu^(1+),and Vo)regulated np-CBO achieved a superb water-splitting photocurrent density of-1.81 m A cm^(-2) under simulated sunlight illumination,which is attributed to the enhanced charge transport and transfer properties resulting from the regulated surface point defects.Finally,the reversibility of the formation of the point defects was checked by sequential RTP treatments(O_(2)-N_(2)-O_(2)-N_(2)),demonstrating the strong dependence of photocurrent response on the RTP cycles.Conclusively,the surface point defect engineering via RTP treatment in a controlled atmosphere is a rapid and facile strategy to promote charge transport and transfer properties of photoelectrodes for efficient solar water-splitting.
基金supported by the National Natural Science Foundation of China (21872105, 22072107)the Science & Technology Commission of Shanghai Municipality (19DZ2271500)。
文摘Aqueous battery-supercapacitor hybrid devices(BSHs)are of great importance to enrich electrochemical energy storage systems with both high energy and power densities.However,further improvement of BSHs in aqueous electrolytes is greatly hampered by operating voltage and capacity limits.Different from the conventional intercalation/de-intercalation mechanism,Bi_(2)O_(3) implements charge storage by a reversible phase conversion mechanism.Herein,taking Bi_(2)O_(3) electrode with wide potential window(from-1.2 to 1 V vs.saturated calomel electrode)and high capacity as battery-type anode,we propose that the overall performance of aqueous BSHs can be greatly upgraded under neutral condition.By paring with stable layer-structuredδ-MnO_(2) cathode,a sodium-ion Bi_(2)O_(3)//MnO_(2) BSH with an ultrahigh voltage of 2.4 V in neutral sodium sulfate electrolyte is developed for the first time.This hybrid device exhibits high capacity(~215 C g^(-1) at 1 mA cm^(-2)),relatively long lifespan(~77.2%capacity retention after 1500 cycles),remarkable energy density(71.7 Wh kg^(-1)@400.5 W kg^(-1))and power density(3204.3 W kg^(-1)@18.8 Wh kg^(-1)).Electrochemical measurements combining a set of spectroscopic techniques reveal the reversible phase conversion between bismuth oxide and metallic bismuth(Bi_(2)O_(3)?Bi0)through Bi^(2+) transition phase in neutral sodium sulfate solution,which can deliver multielectron transfer up to 6,leading to the high-energy BSHs.Our work sheds light on the feasibility of using Bi_(2)O_(3) electrode under neutral condition to address the issue of narrow voltage and low capacity for aqueous BSHs.
基金supported by the National Natural Science Foundation of China(Project.U1604121)and Startup funding from Suzhou University of Science and Technology.
文摘Photoelectrochemical reduction of CO_(2)to produce CO with metal-organic frameworks(MOFs)is recognized as a desirable technology to mitigate CO_(2)emission and generate sustainable energy.To achieve highly efficient electrocatalyst,it is essential to design a new material interface and uncover new reaction mechanisms or kinetics.Herein,we developed two metal-organic Cu-MOF and Bi-MOF layers using benzene tricarboxylic acid(H_(3)BTC)ligands on CuBi_(2)O_(4) photocathodes.Both MOF layers drastically improved the photoelectrochemical stability by suppressing the photo-corrosion through conformal surface passivation.The Cu-MOF modified CuBi_(2)O_(4) showed more significant charge separation and transfer efficiencies than the Bi-MOF modified control.Based on the transient photocurrent curves under the applied potential of 0.6 V vs.RHE,the rate-law analysis showed the CO_(2)photoreduction took place through a first-order reaction.Further,the photoelectrochemical impedance spectra(PEIS)revealed this reaction order,representing an“operando”analysis.Moreover,the reaction rate constant on Cu-MOF modified sample was higher than that on Bi-MOF modified one and bare CuBi_(2)O_(4).Combined with the density functional theory calculation,the surface absorption of CO_(2)and CO molecules and the higher energy barrier for*COOH intermediates could significantly determine the first order reaction.
文摘Core-shell Bi-Bi2 O3/CNT(carbon nanotube) with 3-dimensional neural network structure where Bi-Bi2O3 nanospheres act as cell bodies supported by a 3-dimensional network of CNTs acting as synapses is designed and prepared by simple solvothermal method and subsequent annealing autoreduction treatment,and this structure facilitates the efficient transport of electrons.It can provide two electron transfer paths due to the double contact of Bi2O3 shell with CNT and metal Bi core which enhances the efficiency of the electrochemical reaction.The Bi-Bi2 O3/CNT electrode shows a high gravimetric capacitance of 850 F g-1(1 A g-1),and the specific capacitance of Bi-Bi2O3/CNT can be still 714 F g-1 at 30 A g-1 indicating excellent rate performance.The asymmetric supercapacitor is assembled with Bi-Bi2 O3/CNT as the negative electrode and Ni(OH)2/CNT as the positive electrode,delivering a high energy density of 36.7 Wh kg-1 and a maximum power density of 8000 W kg-1.Therefore,the core-shell Bi-Bi2O3/CNT with 3-dimensional neural network structure as the negative electrode of supercapacitor shows great potential in the field of energy storage in the future.
基金Supported by the National Natural Science Foundation of China(No.60677015)the Science and Technology Department of Zhejiang Province (No.20061664)the Natural Science Foundation of Ningbo (No.2006A610020)
文摘A series of bismuth borate silica glasses were prepared and their densities, linear refractive indices and transmission spectra were measured. The optical gaps Eopt were obtained from the extrapolation of the linear portions to zero absorption. A decrease in the value of Eopt with increasing bismuth content may be explained by suggesting that the non-bridging oxygen ion content increases .It was found that high refractive index and narrow bandgap could lead into high third-order optical nonlinearity.
