Nickel/cobalt-layered double hydroxides(Ni Co-LDH) have been attracted increasing interest in the applications of anode materials for lithium ion battery(LIB), but the low cycle stability and rate performance are stil...Nickel/cobalt-layered double hydroxides(Ni Co-LDH) have been attracted increasing interest in the applications of anode materials for lithium ion battery(LIB), but the low cycle stability and rate performance are still limited its practice applications. To achieve high performance LIB, the surface-confined strategy has been applied to design and fabricate a new anode material of NiCo-LDH nanosheet anchored on the surface of Ti3C2 MXene(Ni Co-LDH/Ti3C2). The ultra-thin, bended and wrinkled α-phase crystal with an interlayer spacing of 8.1 ? can arrange on the conductive substrates Ti3C2 MXene directly, resulting in high electrolyte diffusion ability and low internal resistance. Furthermore, chemical bond interactions between the highly conductive Ti3C2 MXene and Ni Co-LDH nanosheets can greatly increase the ion and electron transport and reduce the volume expansion of NiCo-LDH during Li ion intercalation. As expected,the discharge capacity of 562 m Ah g-1 at 5.0 A g-1 for 800 cycles without degradation can be achieved,rate capability and cycle performance are better than that of NiCo-LDH(~100 mAh g-1). Furthermore, the density function theory(DFT) calculations were performed to demonstrate that Ni Co-LDH/Ti3C2 system can be used as a highly desirable and promising anode material for lithium ion battery.展开更多
Rechargeable lithium-carbon dioxide(Li-CO_(2))batteries have emerged as a highly promising approach to simultaneously address energy shortages and the greenhouse effect.However,certain limitations exist in Li-CO_(2)ba...Rechargeable lithium-carbon dioxide(Li-CO_(2))batteries have emerged as a highly promising approach to simultaneously address energy shortages and the greenhouse effect.However,certain limitations exist in Li-CO_(2)batteries like high charge overpotential and unstable Li metal interface,which adversely affect the energy efficiency and cycling life.The incorporation of soluble redox mediators(RMs)has proven effective in enhancing the charge transfer between lithium carbonate(Li_(2)CO_(3))and cathode,thereby substantially reducing the charge overpotential.Nevertheless,the severe shuttle effect of RMs results in the reactions with Li anode,not only exacerbating the corrosion of Li anode but also leading to the depletion of RMs and electrical energy efficiency.In this work,an organic compound containing large cation group,1-ethyl-3-methylimidazole bromide(EMIBr)is proposed as the defense donor RM for Li anode in Li-CO_(2)batteries to address the above problems simultaneously.During charging,Li_(2)CO_(3)oxidation kinetics can be accelerated by bromide anion pair(Br_(3)^(−)/Br^(−)).Meanwhile,the cations(EMI^(+))are preferentially adsorbed around the protruding tips of Li anode through electrostatic interaction driven by surface free energy,forming protective layers that effectively inhibit further Li deposition at these tips,which is verified by DFT calculations.Additionally,Li dendrites growth is inhibited by the electrostatic repulsion of polar groups in EMIBr,resulting in uniform Li deposition.Consequently,a lower overpotential(∼1.17 V)and a longer cycle life(∼200 cycles)have been obtained for Li-CO_(2)battery incorporating EMIBr.展开更多
LithiumvanadatesLiV_(3)O_(8)-LiV_(6)O_(15)(LVO)witha heterojunction structure are synthesized using a conventional high-temperature solid-state method to address the challenges of low ionic conductivity,rapid capacity...LithiumvanadatesLiV_(3)O_(8)-LiV_(6)O_(15)(LVO)witha heterojunction structure are synthesized using a conventional high-temperature solid-state method to address the challenges of low ionic conductivity,rapid capacity decay,and poor cycling performance in conventional lithium-ion battery cathode materials.The charge-discharge processes of LVO span multiple platforms,delivering an impressive specific discharge capacity of 219.4 mAh.g^(-1) at 1C.Remarkably,LVO exhibits a high-capacity retention rate of 81.3%after 800 cycles within the typical operating voltage range of lithium-ion batteries(2.8-4.3V).Rate capability tests and electrochemical impedance spectroscopy(EIS)reveal that,compared to traditional cathode materials,LVO significantly enhances Li*diffusion rates(D_(Li*))and reduces charge transfer resistance(Ret).展开更多
Self-assembled monolayers(SAMs)are widely used as hole transport materials in inverted perovskite solar cells,offering low parasitic absorption and suitability for semitransparent and tandem solar cells.While SAMs hav...Self-assembled monolayers(SAMs)are widely used as hole transport materials in inverted perovskite solar cells,offering low parasitic absorption and suitability for semitransparent and tandem solar cells.While SAMs have shown to be promising in small-area devices(≤1 cm^(2)),their application in larger areas has been limited by a lack of knowledge regarding alternative deposition methods beyond the common spin-coating approach.Here,we compare spin-coating and upscalable methods such as thermal evaporation and spray-coating for[2-(9H-carbazol-9-yl)ethyl]phosphonic acid(2PACz),one of the most common carbazole-based SAMs.The impact of these deposition methods on the device performance is investigated,revealing that the spray-coating technique yields higher device performance.Furthermore,our work provides guidelines for the deposition of SAM materials for the fabrication of perovskite solar modules.In addition,we provide an extensive characterization of 2PACz films focusing on thermal evaporation and spray-coating methods,which allow for thicker 2PACz deposition.It is found that the optimal 2PACz deposition conditions corresponding to the highest device performances do not always correlate with the monolayer characteristics.展开更多
While the thick growth of intermediate phase layers generally benefits the corrosion resistance of galvanized steels,it is unfavorable from the standpoints of mechanical integrity and economics.Thus,the influence of n...While the thick growth of intermediate phase layers generally benefits the corrosion resistance of galvanized steels,it is unfavorable from the standpoints of mechanical integrity and economics.Thus,the influence of nickel chloride-based fluxes and the typical zinc-ammonium chloride flux on galvanized coating thickness as well as coating morphology and composition is examined.The investigation of pretreated hot dip galvanized steel specimens for various durations has verified that nickel chloride fluxes influence the growth rate of the zeta interlayer.This results in the overall reduction of the coating thickness by as much as two times compared to those prepared with the conventional flux.Nickel from the fluxes gradually diffuses away from the substrate＇s surface,and hence the initial concentration of the nickel salts along with the hot dip duration needs to be controlled appropriately for effective use of nickel chloride-based fluxes in the galvanizing process.展开更多
Developing highly active bifunctional electrocatalysts for oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is of great significance in energy conversion and storage technologies.In this study,we system...Developing highly active bifunctional electrocatalysts for oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is of great significance in energy conversion and storage technologies.In this study,we systematically investigated the OER/ORR electrocatalytic activity of TMN_(4)@G system by using density functional theory(DFT)calculations.Globally,IrN_(4)@G is a very promising bifunctional catalyst for both OER and ORR with the extremely low overpotentials of 0.30 and 0.26 V,respectively.Such outstanding electrocatalytic performance is mainly attributed to the synergistic effect of Ir and N.More importantly,by constructing 2D activity volcano plots,we obtained the limiting overpotentials of TMN_(4)@G system with the values of 0.26 V for OER and 0.24 V for ORR.These findings open up new opportunities for further exploring graphene-based materials for highly efficient OER/ORR electrocatalysts.展开更多
The development of non-precious, high-efficient and durable electrocatalysts for H2 evolution in alkaline media is highly desirable. Herein we report NiCoP nanoleaves array vertically grown on Ni foam for H2 evolution...The development of non-precious, high-efficient and durable electrocatalysts for H2 evolution in alkaline media is highly desirable. Herein we report NiCoP nanoleaves array vertically grown on Ni foam for H2 evolution and overall water splitting via simple hydrothermal treatment and phosphorization. The selfsupported NiCoP nanoleaves architecture contributes to more exposed active sites, the smaller contact resistance between catalyst and substrate, faster ion diffusion and electron transfer. As a result, the optimized electrode requires only overpotentials of 98 and 173 mV to achieve current densities of 10 and100 m A cm-2 in 1.0 M KOH,respectively. Besides, used as both anode and cathode simultaneously, the electrode delivers current densities of 100 and 200 m A cm-2 at cell voltages of only 1.8 and 1.87 V, respectively. Moreover, the relatively high efficiency of about 11.4% for solar-driven water splitting further illustrates the application of our catalyst to sustainable development based on green technologies.展开更多
Charge engineering of carbon materials with many defects shows great potential in electrocatalysis,and molybdenum carbide(Mo2C)is one of the noble-metal-free electrocatalysts with the most potential.Herein,we study th...Charge engineering of carbon materials with many defects shows great potential in electrocatalysis,and molybdenum carbide(Mo2C)is one of the noble-metal-free electrocatalysts with the most potential.Herein,we study the Mo2C on pyridinic nitrogen-doped defective carbon sheets(MoNCs)as catalysts for the hydrogen evolution reaction.Theoretical calculations imply that the introduction of Mo2C produces a graphene wave structure,which in some senses behaves like N doping to form localized charges.Being an active electrocatalyst,MoNCs demonstrate a Tafel slope as low as 60.6 mV dec-1 and high durability of up to 10 h in acidic media.Besides charge engineering,plentiful defects and hierarchical morphology also contribute to good performance.This work underlines the importance of charge engineering to boost catalytic performance.展开更多
The hydrogen evolution reaction (HER) and dendrite growth associated with Zn anode have become the main bottlenecks for the further development of zinc ion batteries (ZIBs).In this work,the electrochemical activity of...The hydrogen evolution reaction (HER) and dendrite growth associated with Zn anode have become the main bottlenecks for the further development of zinc ion batteries (ZIBs).In this work,the electrochemical activity of H_(3)O^(+) is inhibited by the supramolecular host–vip complex composed of H_(3)O^(+) as vip and 18-crown-6 as host.The even Zn plating is induced by the host–vip complex electrostatic shielding layer on Zn anode,as detected by in-situ optical microscopy.The lamellar Zn is plated which profits from the improved Zn plating behavior.Density functional theory (DFT) calculation presents the stable structure of complex.The less produced H_(2) content is monitored online by a mass spectrometer during Zn plating/stripping,which indicates HER can be hampered by the host–vip behavior.Thus,the ZIBs with long life and high Coulombic efficiency are achieved via introducing 18-crown-6.The proposed host–vip supramolecular interaction is expected to facilitate the furthermore development of Zn batteries.展开更多
Open-cell aluminium foams can be produced with the structural replication of dimensional accuracy from polymeric foam patterns through a pressure infiltration casting process.The strength of open-cell foam is much les...Open-cell aluminium foams can be produced with the structural replication of dimensional accuracy from polymeric foam patterns through a pressure infiltration casting process.The strength of open-cell foam is much less than that of the closed-cell counterpart,and thereby subjects to mainly functional applications.An improvement in mechanical properties of the foams can be implemented with the addition of ceramic particles.In the present study,the composite foams were produced using AC3A alloy added with varying contents of SiC particles.The resultant foams have ceramic particles embedded in the alloy matrix and on the strut surface.Higher volume fraction of ceramic particles resulted in an increase in the compressive strength,energy absorption and microhardness of the foams.The improvement of these properties is due to the modification of the microstructure of the foams and the increased strength in the node and struts at which the ceramic particles reside.展开更多
In present study, a simultaneous electrospinning and electrospraying（SEE） process was employed to produce microclusters of TiO2 nanoparticles and interlock them in nanofibrous network. The photocatalytic composite m...In present study, a simultaneous electrospinning and electrospraying（SEE） process was employed to produce microclusters of TiO2 nanoparticles and interlock them in nanofibrous network. The photocatalytic composite membranes（PCMs） were fabricated by electrospraying TiO2 nanoparticle suspension into microcluster form that dispersed and entrapped within nylon-6 electrospun fiber membrane. Three PCMs membrane with TiO2 content of 52.0, 83.6,and 91.7 wt.% were successfully fabricated. The membrane consisted of TiO2 microclusters,ranging in sizes from around 0.3 to 10 μm, distributed uniformly within the nylon-6 nanofibrous network. PCMs photocatalytic activity against Methylene Blue（MB） in aqueous solution showed more than 98% MB removal efficiency after 120 min of photocatalytic oxidation（PCO） for all PCMs. For PCM with the highest TiO2 content tested for 5 PCO cycles, it was found that most of their TiO2 content remained incorporated within the nanofibrous structure. The concept of nanoparticles clusters entrapment with SEE fabrication employed here provide a simple and effective method for reducing detachment of nanostructure phase from nanocomposite membrane.展开更多
Thin and flexible composite solid-state electrolyte(SSE) is considered to be a prospective candidate for lithium-oxygen(Li-O_(2)) batteries with the aim to address the problems of unsatisfied safety, terrible durabili...Thin and flexible composite solid-state electrolyte(SSE) is considered to be a prospective candidate for lithium-oxygen(Li-O_(2)) batteries with the aim to address the problems of unsatisfied safety, terrible durability as well as inferior electrochemical performance. Herein, in order to improve the safety and durability, a succinonitrile(SN) modified composite SSE is proposed. In this SSE, SN is introduced for eliminating the boundary between ceramic particles, increasing the amorphous region of polymer and ensuring fast ionic transport. Subsequently, the symmetric battery based on the proposed SSE achieves a long cycle life of 3000 h. Moreover, the elaborate cathode interface through the SN participation effectively reduces the barriers to the combination between lithium ions and electrons, facilitating the corresponding electrochemical reactions.As a result, the solid-state Li-O_(2)battery based on this SSE and tuned cathode interface achieves improved electrochemical performance including large specific capacity over 12,000 m Ah g^(-1), enhanced rate capacity as well as stable cycle life of 54 cycles at room temperature. This ingenious design provides a new orientation for the evolution of solid-state Li-O_(2)batteries.展开更多
MXene,an emerging two-dimensional(2D)layered material,has received worldwide attention in various energy storage systems because of its excellent properties.Nevertheless,the low capacity of pristine MXene restricts it...MXene,an emerging two-dimensional(2D)layered material,has received worldwide attention in various energy storage systems because of its excellent properties.Nevertheless,the low capacity of pristine MXene restricts its application in energy storage devices especially for the lithium-ion batteries(LIBs).To address the above issue,herein,a stable and highly conductive double transition metal MXene(Ti_(2)NbC_(2)T_(x)) is successfully fabricated,which provides enlarged interlayer spacing and excellent conductivity for fast ion diffusion and charge transfer.Taking the Ti_(2)NbC_(2)T_(x)s anode for LIBs,a superior specific capacity of 196.2 mAh·g-1and an excellent long-term cycling stability of~100%after 400cycles under 0.1 A·g^(-1) are achieved for LIBs.In particular,Ti_(2)NbC_(2)T_(x) delivers an impressive capacity retention of 81%over 4000 cycle under 1 A·g^(-1),outperforming the Ti_(3)C_(2)T_(x) and various previously reported MXene-based materials.Our results offer an attractive strategy for the future application of MXene-based materials.展开更多
The effects of chitosan characteristics including the degree of deacetylation, molecular weight, particle size, pH pretreatment and immobilization time on the immobilization of nitrite-oxidizing bacteria （NOB） on bi...The effects of chitosan characteristics including the degree of deacetylation, molecular weight, particle size, pH pretreatment and immobilization time on the immobilization of nitrite-oxidizing bacteria （NOB） on biopolymeric chitosan were investigated. Nitrite removal efficiency of immobilized NOB depended on the degree of deacetylation, particle size, pH pretreatment on the surface of chitosan and immobilization time. Scanning electron microscope characterization illustrated that the number of NOB cells attached to the surface of chitosan increased with an increment of immobilization time. The optimal condition for NOB immobilization on chitosan was achieved during a 24-hr immobilization period using chitosan with the degree of deacetylation larger than 80% and various particle size ranges between 1-5 mm at pH 6.5. In general, the NOB immobilized on chitosan flakes has a high potential to remove excess nitrite from wastewater and aquaculture systems.展开更多
Electrochemical nitrogen fixation via a convenient and sustainable manner,exhibits an intriguing prospect for ammonia generation under ambient conditions.Currently,the design and development of high-efficiency and low...Electrochemical nitrogen fixation via a convenient and sustainable manner,exhibits an intriguing prospect for ammonia generation under ambient conditions.Currently,the design and development of high-efficiency and low-cost electrocatalysts remains the major challenge confronting nitrogen reduction reaction(NRR).Herein,anchoring the single Mo atom on the C_(9)N_(4) substrate(Mo@C_(9)N_(4)) to form an efficient single-atom catalyst(SAC) is proposed for the conversion of N2 to NH3.By employing density functional theory(DFT) calculations,we demonstrated that gas phase N2 can be sufficiently activated and efficiently reduced to NH3 on the surface of Mo@C_(9)N_(4).Meanwhile,we found that the NRR dominantly occurred on the Mo center via a preferred distal pathway with favorable limiting potential of 0.40 V.Importantly,the as-established Mo@C_(9)N_(4) catalyst exhibits an outstanding structural stability and good selectivity toward NRR.These findings provide a promising platform for designing Mo-based SACs for electrochemical N2 fixation.展开更多
Constructing a protective layer on Zn anode surface with high lattice matching to Zn(002)can facilitate preferential growth along the(002)crystal plane and suppress dendritic growth as well as interface side reactions...Constructing a protective layer on Zn anode surface with high lattice matching to Zn(002)can facilitate preferential growth along the(002)crystal plane and suppress dendritic growth as well as interface side reactions.Whereas most of protective layers are complex and costly,making commercial applications challenging.Herein,we introduce a facile method involving the addition of CuCl_(2) electrolyte additives to conventional electrolyte systems,which,through rapid displacement reactions and controlled electrochemical cycling,forms a CuZn_(5) alloy layer with 97.2%lattice matching to the(002)plane(CuZn_(5)@Zn),thus regulating the(002)plane epitaxial deposition.As a result,the symmetric cells with CuZn_(5)@Zn demonstrate an ultra-long cycle life of 3600 h at 1 mA cm^(-2).Under extreme conditions of high current density(20 m A cm^(-2))and high zinc utilization(DOD_(Zn)=50%),stable cycling performance is maintained for 220 and 350 h,respectively.Furthermore,the CuZn_(5)@Zn||NH_(4)V_(4)O_(10)full cell maintains a capacity of 120 m A h g^(-1)even after 10,000 cycles at a high current density of 10 A g^(-1).This work presents a facile and efficient strategy for constructing stable metal anode materials,with implications for the development of next-generation rechargeable batteries.展开更多
Polypropylene（PP） meltblown fibers were coated with titanium dioxide（Ti O2） nanoparticles using layer-by-layer（Lb L） deposition technique. The fibers were first modified with 3layers of poly（4-styrenesulfonic a...Polypropylene（PP） meltblown fibers were coated with titanium dioxide（Ti O2） nanoparticles using layer-by-layer（Lb L） deposition technique. The fibers were first modified with 3layers of poly（4-styrenesulfonic acid）（PSS） and poly（diallyl-dimethylammonium chloride）（PDADMAC） to improve the anchoring of the Ti O2 nanoparticle clusters. PDADMAC, which is positively charged, was then used as counter polyelectrolyte in tandem with anionic Ti O2 nanoparticles to construct Ti O2/PDADMAC bilayer in the Lb L fashion. The number of deposited Ti O2/PDADMAC layers was varied from 1 to 7 bilayer, and could be used to adjust Ti O2 loading. The Lb L technique showed higher Ti O2 loading efficiency than the impregnation approach. The modified fibers were tested for their photocatalytic activity against a model dye, Methylene Blue（MB）. Results showed that the Ti O2 modified fibers exhibited excellent photocatalytic activity efficiency similar to that of Ti O2 powder dispersed in solution. The deposition of Ti O23 bilayer on the PP substrate was sufficient to produce nanocomposite fibers that could bleach the MB solution in less than 4 hr.Ti O2-Lb L constructions also preserved Ti O2 adhesion on substrate surface after 1 cycle of photocatalytic test. Successive photocatalytic test showed decline in MB reduction rate with loss of Ti O2 particles from the substrate outer surface. However, even in the third cycle, the Ti O2 modified fibers are still moderately effective as it could remove more than 95% of MB after 8 hr of treatment.展开更多
Solid-state sodium batteries(SSSBs)are poised to replace lithium-ion batteries as viable alternatives for energy storage systems owing to their high safety and reliability,abundance of raw material,and low costs.Howev...Solid-state sodium batteries(SSSBs)are poised to replace lithium-ion batteries as viable alternatives for energy storage systems owing to their high safety and reliability,abundance of raw material,and low costs.However,as the core constituent of SSSBs,solid-state electrolytes(SSEs)with low ionic conductivities at room temperature(RT)and unstable interfaces with electrodes hinder the development of SSSBs.Recently,composite SSEs(CSSEs),which inherit the desirable properties of two phases,high RT ionic conductivity,and high interfacial stability,have emerged as viable alternatives;however,their governing mechanism remains unclear.In this review,we summarize the recent research progress of CSSEs,classified into inorganic-inorganic,polymer-polymer,and inorganic-polymer types,and discuss their structure-property relationship in detail.Moreover,the CSSE-electrode interface issues and effective strategies to promote intimate and stable interfaces are summarized.Finally,the trends in the design of CSSEs and CSSE-electrode interfaces are presented,along with the future development prospects of high-performance SSSBs.展开更多
The uncontrollable dendrites growth and intricately water-induced side reactions occurred on zinc anode leads to safety issues and poor electrochemical kinetics,which largely limit the widespread application of zinc-i...The uncontrollable dendrites growth and intricately water-induced side reactions occurred on zinc anode leads to safety issues and poor electrochemical kinetics,which largely limit the widespread application of zinc-ion batteries(ZIBs).Herein,ethylenediaminetetraacetic acid disodium salt(EDTA-2Na)is utilized as an electrolyte additive to strengthen the reversibility and cycling stability of zinc anode.Experimental results and theoretical calculation demonstrate that the EDTA-2Na presents a much stronger coordination with Zn^(2+)when comparing with H_(2)O molecular,implying the EDTA-2Na is capable to enter the solvation shell of[Zn(OH_(2))_(6)]^(2+)and coordinate with Zn^(2+)ions,thus achieving a flat and smooth zinc deposition with less by-products(Zn_(4)SO_(4)(OH)6·xH_(2)O and H_(2)).Consequently,the zinc symmetric battery with EDTA-2Na additive delivers an excellent cycling stability up to 1800 h under current density of 1 mA cm^(-2),and the hydrogen evolution reaction(HER),corrosion,by-product issues are significantly inhibited.Moreover,the rate performance and stability of coin-type and pouch-type Zn||MnO2/graphite batteries are significantly boosted via EDTA-2Na additive(248 mAh g^(-1)at 0.1 A g^(-1),81.3%after 1000 cycles at a A g^(-1)).This kind of electrolyte additive with chelation and desolvation functions shed lights on strategies of improving zinc anode stability for further application of ZIBs.展开更多
Impurity segregation even small amounts,can drastically change the cohesive properties of the grain boundaries(GB),eventually leading to intergranular embrittlement and failure of the materials,thereby effectively con...Impurity segregation even small amounts,can drastically change the cohesive properties of the grain boundaries(GB),eventually leading to intergranular embrittlement and failure of the materials,thereby effectively controlling the types and the concentrations of the impurity is very important.In this work,the nonmetallic impurities(C,H,O,N) segregation and their effects on the strength of Zr(10 1 2) GB were thoroughly investigated using first-principles calculations based on density functional theory.A comprehensive analysis of the interstitial configurations and the relative site energies indicating that C,N and O overwhelmingly prefer the octahedral sites,only H,prefers to reside in the tetrahedral sites.Moreover,the strengthening/embrittlement potency of impurity atoms on the GB was estimated using both the Rice-Wang model and first-principles tensile test calculations.The results show that all impurities,exhibit a strong segregation tendency near the GB region.The segregation of C,N and O has a remarkable strengthening effect on strength of the GB,whereas the presence of impurity H weaken the GB.Most importantly,the underlying mechanism of the strength change of the GBs due to the segregation of impurities was profoundly discussed by charge density and the bond lengths analyses,revealing that the strengthening effect especially for C-doped GB,mainly comes from an enhancement of the charge density across the GB plane.In the end,we expect that our results will be certainly useful for future theoretical and experimental investigations on Zr and its alloys.展开更多
基金Rachadapisek Sompoch project,Chulalongkorn University(CU_GR_62_14_62_02)the Energy Conservation and Promotion Fund Office,Ministry of Energy+2 种基金the NSFC(grant 51421091)National Science Foundation for Distinguished Young Scholars for Hebei Province of China(grant E2016203376)Asahi Glass Foundation。
文摘Nickel/cobalt-layered double hydroxides(Ni Co-LDH) have been attracted increasing interest in the applications of anode materials for lithium ion battery(LIB), but the low cycle stability and rate performance are still limited its practice applications. To achieve high performance LIB, the surface-confined strategy has been applied to design and fabricate a new anode material of NiCo-LDH nanosheet anchored on the surface of Ti3C2 MXene(Ni Co-LDH/Ti3C2). The ultra-thin, bended and wrinkled α-phase crystal with an interlayer spacing of 8.1 ? can arrange on the conductive substrates Ti3C2 MXene directly, resulting in high electrolyte diffusion ability and low internal resistance. Furthermore, chemical bond interactions between the highly conductive Ti3C2 MXene and Ni Co-LDH nanosheets can greatly increase the ion and electron transport and reduce the volume expansion of NiCo-LDH during Li ion intercalation. As expected,the discharge capacity of 562 m Ah g-1 at 5.0 A g-1 for 800 cycles without degradation can be achieved,rate capability and cycle performance are better than that of NiCo-LDH(~100 mAh g-1). Furthermore, the density function theory(DFT) calculations were performed to demonstrate that Ni Co-LDH/Ti3C2 system can be used as a highly desirable and promising anode material for lithium ion battery.
基金financially supported by National Natural Science Foundation of China(No.22075171).
文摘Rechargeable lithium-carbon dioxide(Li-CO_(2))batteries have emerged as a highly promising approach to simultaneously address energy shortages and the greenhouse effect.However,certain limitations exist in Li-CO_(2)batteries like high charge overpotential and unstable Li metal interface,which adversely affect the energy efficiency and cycling life.The incorporation of soluble redox mediators(RMs)has proven effective in enhancing the charge transfer between lithium carbonate(Li_(2)CO_(3))and cathode,thereby substantially reducing the charge overpotential.Nevertheless,the severe shuttle effect of RMs results in the reactions with Li anode,not only exacerbating the corrosion of Li anode but also leading to the depletion of RMs and electrical energy efficiency.In this work,an organic compound containing large cation group,1-ethyl-3-methylimidazole bromide(EMIBr)is proposed as the defense donor RM for Li anode in Li-CO_(2)batteries to address the above problems simultaneously.During charging,Li_(2)CO_(3)oxidation kinetics can be accelerated by bromide anion pair(Br_(3)^(−)/Br^(−)).Meanwhile,the cations(EMI^(+))are preferentially adsorbed around the protruding tips of Li anode through electrostatic interaction driven by surface free energy,forming protective layers that effectively inhibit further Li deposition at these tips,which is verified by DFT calculations.Additionally,Li dendrites growth is inhibited by the electrostatic repulsion of polar groups in EMIBr,resulting in uniform Li deposition.Consequently,a lower overpotential(∼1.17 V)and a longer cycle life(∼200 cycles)have been obtained for Li-CO_(2)battery incorporating EMIBr.
基金supported by the National Natural Science Foundation of China(Nos.52125405 and U22A20108)Thailand Science Research and Innovation Fund Chulalongkorn University,National Research Council of Thailand(NRCT)+1 种基金Chulalongkorn University(No.42A660383)the Hub of Talents:Sustainable Materials for Circular Economy,National Research Council of Thailand(NRCT).
文摘LithiumvanadatesLiV_(3)O_(8)-LiV_(6)O_(15)(LVO)witha heterojunction structure are synthesized using a conventional high-temperature solid-state method to address the challenges of low ionic conductivity,rapid capacity decay,and poor cycling performance in conventional lithium-ion battery cathode materials.The charge-discharge processes of LVO span multiple platforms,delivering an impressive specific discharge capacity of 219.4 mAh.g^(-1) at 1C.Remarkably,LVO exhibits a high-capacity retention rate of 81.3%after 800 cycles within the typical operating voltage range of lithium-ion batteries(2.8-4.3V).Rate capability tests and electrochemical impedance spectroscopy(EIS)reveal that,compared to traditional cathode materials,LVO significantly enhances Li*diffusion rates(D_(Li*))and reduces charge transfer resistance(Ret).
基金supported by funding from the Energy Materials and Surface Sciences Unit of the Okinawa Institute of Science and Technology Graduate University,the OIST R&D Cluster Research Program,the OIST Proof of Concept(POC)Program,the JSPS KAKENHI Grant Number JP21F21754 and Alexander von Humboldt Foundation。
文摘Self-assembled monolayers(SAMs)are widely used as hole transport materials in inverted perovskite solar cells,offering low parasitic absorption and suitability for semitransparent and tandem solar cells.While SAMs have shown to be promising in small-area devices(≤1 cm^(2)),their application in larger areas has been limited by a lack of knowledge regarding alternative deposition methods beyond the common spin-coating approach.Here,we compare spin-coating and upscalable methods such as thermal evaporation and spray-coating for[2-(9H-carbazol-9-yl)ethyl]phosphonic acid(2PACz),one of the most common carbazole-based SAMs.The impact of these deposition methods on the device performance is investigated,revealing that the spray-coating technique yields higher device performance.Furthermore,our work provides guidelines for the deposition of SAM materials for the fabrication of perovskite solar modules.In addition,we provide an extensive characterization of 2PACz films focusing on thermal evaporation and spray-coating methods,which allow for thicker 2PACz deposition.It is found that the optimal 2PACz deposition conditions corresponding to the highest device performances do not always correlate with the monolayer characteristics.
基金Item Sponsored by Iron and Steel Institute of Thailand(ISIT) for Research Funding(022/2552)
文摘While the thick growth of intermediate phase layers generally benefits the corrosion resistance of galvanized steels,it is unfavorable from the standpoints of mechanical integrity and economics.Thus,the influence of nickel chloride-based fluxes and the typical zinc-ammonium chloride flux on galvanized coating thickness as well as coating morphology and composition is examined.The investigation of pretreated hot dip galvanized steel specimens for various durations has verified that nickel chloride fluxes influence the growth rate of the zeta interlayer.This results in the overall reduction of the coating thickness by as much as two times compared to those prepared with the conventional flux.Nickel from the fluxes gradually diffuses away from the substrate＇s surface,and hence the initial concentration of the nickel salts along with the hot dip duration needs to be controlled appropriately for effective use of nickel chloride-based fluxes in the galvanizing process.
基金supported by the National Science Foundation for Distinguished Young Scholars for Hebei Province of China(grant E2016203376)the Thailand Research Fund(RSA6080017)the Energy Conservation Promotion Fund and the Energy Conservation Promotion Fund Office,Ministry of Energy。
文摘Developing highly active bifunctional electrocatalysts for oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)is of great significance in energy conversion and storage technologies.In this study,we systematically investigated the OER/ORR electrocatalytic activity of TMN_(4)@G system by using density functional theory(DFT)calculations.Globally,IrN_(4)@G is a very promising bifunctional catalyst for both OER and ORR with the extremely low overpotentials of 0.30 and 0.26 V,respectively.Such outstanding electrocatalytic performance is mainly attributed to the synergistic effect of Ir and N.More importantly,by constructing 2D activity volcano plots,we obtained the limiting overpotentials of TMN_(4)@G system with the values of 0.26 V for OER and 0.24 V for ORR.These findings open up new opportunities for further exploring graphene-based materials for highly efficient OER/ORR electrocatalysts.
基金the financial support from the Changsha Science and Technology Plan(kq1801065)Hunan Provincial Science and Technology Plan Project(No.2017TP1001)+1 种基金state Key Laboratory Fundthe postdoctoral research funding plan in Central South University(Grant No.140050022)。
文摘The development of non-precious, high-efficient and durable electrocatalysts for H2 evolution in alkaline media is highly desirable. Herein we report NiCoP nanoleaves array vertically grown on Ni foam for H2 evolution and overall water splitting via simple hydrothermal treatment and phosphorization. The selfsupported NiCoP nanoleaves architecture contributes to more exposed active sites, the smaller contact resistance between catalyst and substrate, faster ion diffusion and electron transfer. As a result, the optimized electrode requires only overpotentials of 98 and 173 mV to achieve current densities of 10 and100 m A cm-2 in 1.0 M KOH,respectively. Besides, used as both anode and cathode simultaneously, the electrode delivers current densities of 100 and 200 m A cm-2 at cell voltages of only 1.8 and 1.87 V, respectively. Moreover, the relatively high efficiency of about 11.4% for solar-driven water splitting further illustrates the application of our catalyst to sustainable development based on green technologies.
基金the financial support from Changsha Science and Technology Plan (kq1801065)Hunan Provincial Science and Technology Plan Project (No. 2017TP1001)+5 种基金State Key Laboratory Fundthe National Key R&D Program of China (2018YFB0704100)the NSFC grant (No. 11627901)the Scientific Challenge Project of China (No. TZ2018001)the visit at the National Joint Engineering Laboratory of Power Grid with Electric Vehicles (Shandong University)supported by the IMD supercomputing center
文摘Charge engineering of carbon materials with many defects shows great potential in electrocatalysis,and molybdenum carbide(Mo2C)is one of the noble-metal-free electrocatalysts with the most potential.Herein,we study the Mo2C on pyridinic nitrogen-doped defective carbon sheets(MoNCs)as catalysts for the hydrogen evolution reaction.Theoretical calculations imply that the introduction of Mo2C produces a graphene wave structure,which in some senses behaves like N doping to form localized charges.Being an active electrocatalyst,MoNCs demonstrate a Tafel slope as low as 60.6 mV dec-1 and high durability of up to 10 h in acidic media.Besides charge engineering,plentiful defects and hierarchical morphology also contribute to good performance.This work underlines the importance of charge engineering to boost catalytic performance.
基金the partial financial support from the National Natural Science Foundation of China (22075171)。
文摘The hydrogen evolution reaction (HER) and dendrite growth associated with Zn anode have become the main bottlenecks for the further development of zinc ion batteries (ZIBs).In this work,the electrochemical activity of H_(3)O^(+) is inhibited by the supramolecular host–vip complex composed of H_(3)O^(+) as vip and 18-crown-6 as host.The even Zn plating is induced by the host–vip complex electrostatic shielding layer on Zn anode,as detected by in-situ optical microscopy.The lamellar Zn is plated which profits from the improved Zn plating behavior.Density functional theory (DFT) calculation presents the stable structure of complex.The less produced H_(2) content is monitored online by a mass spectrometer during Zn plating/stripping,which indicates HER can be hampered by the host–vip behavior.Thus,the ZIBs with long life and high Coulombic efficiency are achieved via introducing 18-crown-6.The proposed host–vip supramolecular interaction is expected to facilitate the furthermore development of Zn batteries.
基金a research grant 'The 90th Anniversary of Chulalongkorn University Fund (Ratchadaphiseksomphot Endowment Fund)' for the present research work
文摘Open-cell aluminium foams can be produced with the structural replication of dimensional accuracy from polymeric foam patterns through a pressure infiltration casting process.The strength of open-cell foam is much less than that of the closed-cell counterpart,and thereby subjects to mainly functional applications.An improvement in mechanical properties of the foams can be implemented with the addition of ceramic particles.In the present study,the composite foams were produced using AC3A alloy added with varying contents of SiC particles.The resultant foams have ceramic particles embedded in the alloy matrix and on the strut surface.Higher volume fraction of ceramic particles resulted in an increase in the compressive strength,energy absorption and microhardness of the foams.The improvement of these properties is due to the modification of the microstructure of the foams and the increased strength in the node and struts at which the ceramic particles reside.
基金supported by the 90th Anniversary of Chulalongkorn University,Rachadapisek Sompote Fund,Chulalongkorn University,through the Nanotec–CU Center of Excellence on Food and AgricultureInternational Program in Hazardous Substance, and Environmental Management Center of Excellence on Hazardous Substance Management(HSM)Chulalongkorn University
文摘In present study, a simultaneous electrospinning and electrospraying（SEE） process was employed to produce microclusters of TiO2 nanoparticles and interlock them in nanofibrous network. The photocatalytic composite membranes（PCMs） were fabricated by electrospraying TiO2 nanoparticle suspension into microcluster form that dispersed and entrapped within nylon-6 electrospun fiber membrane. Three PCMs membrane with TiO2 content of 52.0, 83.6,and 91.7 wt.% were successfully fabricated. The membrane consisted of TiO2 microclusters,ranging in sizes from around 0.3 to 10 μm, distributed uniformly within the nylon-6 nanofibrous network. PCMs photocatalytic activity against Methylene Blue（MB） in aqueous solution showed more than 98% MB removal efficiency after 120 min of photocatalytic oxidation（PCO） for all PCMs. For PCM with the highest TiO2 content tested for 5 PCO cycles, it was found that most of their TiO2 content remained incorporated within the nanofibrous structure. The concept of nanoparticles clusters entrapment with SEE fabrication employed here provide a simple and effective method for reducing detachment of nanostructure phase from nanocomposite membrane.
基金the partial financial support from the National Natural Science Foundation of China (22075171,21805182 and 22179080)。
文摘Thin and flexible composite solid-state electrolyte(SSE) is considered to be a prospective candidate for lithium-oxygen(Li-O_(2)) batteries with the aim to address the problems of unsatisfied safety, terrible durability as well as inferior electrochemical performance. Herein, in order to improve the safety and durability, a succinonitrile(SN) modified composite SSE is proposed. In this SSE, SN is introduced for eliminating the boundary between ceramic particles, increasing the amorphous region of polymer and ensuring fast ionic transport. Subsequently, the symmetric battery based on the proposed SSE achieves a long cycle life of 3000 h. Moreover, the elaborate cathode interface through the SN participation effectively reduces the barriers to the combination between lithium ions and electrons, facilitating the corresponding electrochemical reactions.As a result, the solid-state Li-O_(2)battery based on this SSE and tuned cathode interface achieves improved electrochemical performance including large specific capacity over 12,000 m Ah g^(-1), enhanced rate capacity as well as stable cycle life of 54 cycles at room temperature. This ingenious design provides a new orientation for the evolution of solid-state Li-O_(2)batteries.
基金supported by the National Science,Research and Innovation Fund(NSRF)via the Program Management Unit for Human Resources&Institutional Development,Research and Innovation(No.B05F640153)the National Research Council of Thailand(NRCT)(No.NRCT5-RSA63001-19)+2 种基金the National Natural Science Foundation of China(No.52125405)the National Key R&D Program of China(No.2018YFA0703602)financially supporting from the Second Century Fund(C2F),Chulalongkorn University。
文摘MXene,an emerging two-dimensional(2D)layered material,has received worldwide attention in various energy storage systems because of its excellent properties.Nevertheless,the low capacity of pristine MXene restricts its application in energy storage devices especially for the lithium-ion batteries(LIBs).To address the above issue,herein,a stable and highly conductive double transition metal MXene(Ti_(2)NbC_(2)T_(x)) is successfully fabricated,which provides enlarged interlayer spacing and excellent conductivity for fast ion diffusion and charge transfer.Taking the Ti_(2)NbC_(2)T_(x)s anode for LIBs,a superior specific capacity of 196.2 mAh·g-1and an excellent long-term cycling stability of~100%after 400cycles under 0.1 A·g^(-1) are achieved for LIBs.In particular,Ti_(2)NbC_(2)T_(x) delivers an impressive capacity retention of 81%over 4000 cycle under 1 A·g^(-1),outperforming the Ti_(3)C_(2)T_(x) and various previously reported MXene-based materials.Our results offer an attractive strategy for the future application of MXene-based materials.
基金supported by the Ratchadaphiseksomphot Endowment Fund
文摘The effects of chitosan characteristics including the degree of deacetylation, molecular weight, particle size, pH pretreatment and immobilization time on the immobilization of nitrite-oxidizing bacteria （NOB） on biopolymeric chitosan were investigated. Nitrite removal efficiency of immobilized NOB depended on the degree of deacetylation, particle size, pH pretreatment on the surface of chitosan and immobilization time. Scanning electron microscope characterization illustrated that the number of NOB cells attached to the surface of chitosan increased with an increment of immobilization time. The optimal condition for NOB immobilization on chitosan was achieved during a 24-hr immobilization period using chitosan with the degree of deacetylation larger than 80% and various particle size ranges between 1-5 mm at pH 6.5. In general, the NOB immobilized on chitosan flakes has a high potential to remove excess nitrite from wastewater and aquaculture systems.
基金supported by the National Science Foundation for Distinguished Young Scholars for Hebei Province of China(grant E2016203376)NSFC(grant 51571174)。
文摘Electrochemical nitrogen fixation via a convenient and sustainable manner,exhibits an intriguing prospect for ammonia generation under ambient conditions.Currently,the design and development of high-efficiency and low-cost electrocatalysts remains the major challenge confronting nitrogen reduction reaction(NRR).Herein,anchoring the single Mo atom on the C_(9)N_(4) substrate(Mo@C_(9)N_(4)) to form an efficient single-atom catalyst(SAC) is proposed for the conversion of N2 to NH3.By employing density functional theory(DFT) calculations,we demonstrated that gas phase N2 can be sufficiently activated and efficiently reduced to NH3 on the surface of Mo@C_(9)N_(4).Meanwhile,we found that the NRR dominantly occurred on the Mo center via a preferred distal pathway with favorable limiting potential of 0.40 V.Importantly,the as-established Mo@C_(9)N_(4) catalyst exhibits an outstanding structural stability and good selectivity toward NRR.These findings provide a promising platform for designing Mo-based SACs for electrochemical N2 fixation.
基金financially supported by the National Key R&D Program of China(2022YFB3807700)the National Natural Science Foundation of China(Grant no.52125405 and U22A20108)+4 种基金the support from the Hubei Provincial Natural Science Foundation of China(Grant No.2023AFB155)the opening project of State Key Laboratory of Metastable Materials Science and Technology(Yanshan University)(opening project number:202401,202404)the Thailand Science Research and Innovation Fund Chulalongkorn University(INDF67620003)the National Science,Research and Innovation Fund(NSRF)via the Program Management Unit for Human Resources&Institutional Development,Research and Innovation(Grant no.B05F640153)the National Research Council of Thailand(NRCT)and Chulalongkorn University(N42A660383)。
文摘Constructing a protective layer on Zn anode surface with high lattice matching to Zn(002)can facilitate preferential growth along the(002)crystal plane and suppress dendritic growth as well as interface side reactions.Whereas most of protective layers are complex and costly,making commercial applications challenging.Herein,we introduce a facile method involving the addition of CuCl_(2) electrolyte additives to conventional electrolyte systems,which,through rapid displacement reactions and controlled electrochemical cycling,forms a CuZn_(5) alloy layer with 97.2%lattice matching to the(002)plane(CuZn_(5)@Zn),thus regulating the(002)plane epitaxial deposition.As a result,the symmetric cells with CuZn_(5)@Zn demonstrate an ultra-long cycle life of 3600 h at 1 mA cm^(-2).Under extreme conditions of high current density(20 m A cm^(-2))and high zinc utilization(DOD_(Zn)=50%),stable cycling performance is maintained for 220 and 350 h,respectively.Furthermore,the CuZn_(5)@Zn||NH_(4)V_(4)O_(10)full cell maintains a capacity of 120 m A h g^(-1)even after 10,000 cycles at a high current density of 10 A g^(-1).This work presents a facile and efficient strategy for constructing stable metal anode materials,with implications for the development of next-generation rechargeable batteries.
基金supported by Rachadapisek Sompote Fund for Postdoctoral Fellowship, Chulalongkorn University, Thailandthe Nanotechnology Center (NANOTEC), NSTDA Ministry of Science and Technology, Thailand, through its program of Center of Excellence Network+1 种基金National Research University Project of CHEthe Rachadapisek Sompote Endowment Fund (No. AM1041A)
文摘Polypropylene（PP） meltblown fibers were coated with titanium dioxide（Ti O2） nanoparticles using layer-by-layer（Lb L） deposition technique. The fibers were first modified with 3layers of poly（4-styrenesulfonic acid）（PSS） and poly（diallyl-dimethylammonium chloride）（PDADMAC） to improve the anchoring of the Ti O2 nanoparticle clusters. PDADMAC, which is positively charged, was then used as counter polyelectrolyte in tandem with anionic Ti O2 nanoparticles to construct Ti O2/PDADMAC bilayer in the Lb L fashion. The number of deposited Ti O2/PDADMAC layers was varied from 1 to 7 bilayer, and could be used to adjust Ti O2 loading. The Lb L technique showed higher Ti O2 loading efficiency than the impregnation approach. The modified fibers were tested for their photocatalytic activity against a model dye, Methylene Blue（MB）. Results showed that the Ti O2 modified fibers exhibited excellent photocatalytic activity efficiency similar to that of Ti O2 powder dispersed in solution. The deposition of Ti O23 bilayer on the PP substrate was sufficient to produce nanocomposite fibers that could bleach the MB solution in less than 4 hr.Ti O2-Lb L constructions also preserved Ti O2 adhesion on substrate surface after 1 cycle of photocatalytic test. Successive photocatalytic test showed decline in MB reduction rate with loss of Ti O2 particles from the substrate outer surface. However, even in the third cycle, the Ti O2 modified fibers are still moderately effective as it could remove more than 95% of MB after 8 hr of treatment.
基金China Postdoctoral Science Foundation,Grant/Award Numbers:2022TQ0065,2023M730614Science and Technology Commission of Shanghai Municipality,Grant/Award Numbers:21ZR1409300,23160714000+3 种基金Shanghai Post-doctoral Excellence Program,Grant/Award Number:2022029Thail and Science research and Innovation Fund Chulalongkorn University,The Program Management Unit for Human Resources&Institutional Development,Research and Innovation,Grant/Award Number:B41G670026National Key Research and Development Program of China,Grant/Award Number:2022YFB2502004Key Basic Research Program of Science and Technology Commission of Shanghai Municipality,Grant/Award Number:23520750400。
文摘Solid-state sodium batteries(SSSBs)are poised to replace lithium-ion batteries as viable alternatives for energy storage systems owing to their high safety and reliability,abundance of raw material,and low costs.However,as the core constituent of SSSBs,solid-state electrolytes(SSEs)with low ionic conductivities at room temperature(RT)and unstable interfaces with electrodes hinder the development of SSSBs.Recently,composite SSEs(CSSEs),which inherit the desirable properties of two phases,high RT ionic conductivity,and high interfacial stability,have emerged as viable alternatives;however,their governing mechanism remains unclear.In this review,we summarize the recent research progress of CSSEs,classified into inorganic-inorganic,polymer-polymer,and inorganic-polymer types,and discuss their structure-property relationship in detail.Moreover,the CSSE-electrode interface issues and effective strategies to promote intimate and stable interfaces are summarized.Finally,the trends in the design of CSSEs and CSSE-electrode interfaces are presented,along with the future development prospects of high-performance SSSBs.
基金supported from the National Research Council of Thailand(NRCT):NRCT-RSA63001-19Second Century Fund(C2F),Chulalongkorn University.
文摘The uncontrollable dendrites growth and intricately water-induced side reactions occurred on zinc anode leads to safety issues and poor electrochemical kinetics,which largely limit the widespread application of zinc-ion batteries(ZIBs).Herein,ethylenediaminetetraacetic acid disodium salt(EDTA-2Na)is utilized as an electrolyte additive to strengthen the reversibility and cycling stability of zinc anode.Experimental results and theoretical calculation demonstrate that the EDTA-2Na presents a much stronger coordination with Zn^(2+)when comparing with H_(2)O molecular,implying the EDTA-2Na is capable to enter the solvation shell of[Zn(OH_(2))_(6)]^(2+)and coordinate with Zn^(2+)ions,thus achieving a flat and smooth zinc deposition with less by-products(Zn_(4)SO_(4)(OH)6·xH_(2)O and H_(2)).Consequently,the zinc symmetric battery with EDTA-2Na additive delivers an excellent cycling stability up to 1800 h under current density of 1 mA cm^(-2),and the hydrogen evolution reaction(HER),corrosion,by-product issues are significantly inhibited.Moreover,the rate performance and stability of coin-type and pouch-type Zn||MnO2/graphite batteries are significantly boosted via EDTA-2Na additive(248 mAh g^(-1)at 0.1 A g^(-1),81.3%after 1000 cycles at a A g^(-1)).This kind of electrolyte additive with chelation and desolvation functions shed lights on strategies of improving zinc anode stability for further application of ZIBs.
基金supported financially by the National Natural Science Foundation of China(No.51571174)the National Science Foundation for Distinguished Young Scholars for Hebei Province of China(No.E2016203376)the Hundred Excellent Innovative Talents Support Program in Hebei Province(No.SLRC2017056)。
文摘Impurity segregation even small amounts,can drastically change the cohesive properties of the grain boundaries(GB),eventually leading to intergranular embrittlement and failure of the materials,thereby effectively controlling the types and the concentrations of the impurity is very important.In this work,the nonmetallic impurities(C,H,O,N) segregation and their effects on the strength of Zr(10 1 2) GB were thoroughly investigated using first-principles calculations based on density functional theory.A comprehensive analysis of the interstitial configurations and the relative site energies indicating that C,N and O overwhelmingly prefer the octahedral sites,only H,prefers to reside in the tetrahedral sites.Moreover,the strengthening/embrittlement potency of impurity atoms on the GB was estimated using both the Rice-Wang model and first-principles tensile test calculations.The results show that all impurities,exhibit a strong segregation tendency near the GB region.The segregation of C,N and O has a remarkable strengthening effect on strength of the GB,whereas the presence of impurity H weaken the GB.Most importantly,the underlying mechanism of the strength change of the GBs due to the segregation of impurities was profoundly discussed by charge density and the bond lengths analyses,revealing that the strengthening effect especially for C-doped GB,mainly comes from an enhancement of the charge density across the GB plane.In the end,we expect that our results will be certainly useful for future theoretical and experimental investigations on Zr and its alloys.
