Large-scale hydrogen production via water electrolysis faces a freshwater shortage.Direct seawater electrolysis offers a solution but encounters new challenges.Herein,we report a feasible strategy to both prevent meta...Large-scale hydrogen production via water electrolysis faces a freshwater shortage.Direct seawater electrolysis offers a solution but encounters new challenges.Herein,we report a feasible strategy to both prevent metal hydroxides deposition and boost the hydrogen evolution reaction by adding a chelating agent,EDTA-Na_(4),that chelates with Mg^(2+)/Ca^(2+),thus inhibiting their deposition and gathering them near the cathode surface,resulting in breaking the ordered hydrogen bond networks of interfacial water and reducing the activation energy of water dissociation.Furthermore,hydrolysis of–COO^(-) also promoted water dissociation to produce more active*H and*OH near the electrode surface that in turn serves as a diffusion medium for*OH,accelerating mass transfer and enabling seawater electrolysis to exhibit a stable performance,which operates continuously at 100 mA cm^(-2)@2.20 V and 200 mA cm^(-2)@2.58 V for 400 h in the symmetric electrolyzer and 500 mA cm^(-2)@2.29 V for over 500 h in the asymmetric electrolyzer.This study provides a new perspective to address the issues of stable and scalable direct seawater electrolysis for practical green hydrogen production.展开更多
NiFe-layered double hydroxides(NiFe-LDHs)are among the most promising earth-abundant electrocatalysts for the oxygen evolution reaction(OER)in alkaline media.However,their practical application is hindered by intrinsi...NiFe-layered double hydroxides(NiFe-LDHs)are among the most promising earth-abundant electrocatalysts for the oxygen evolution reaction(OER)in alkaline media.However,their practical application is hindered by intrinsic activity limitations and poor stability,primarily due to the asymmetric adsorption of oxygen intermediates.To overcome this,the binding strength must be synergistically tuned to a moderate level to optimize catalytic performance.Here,we engineered NiFeCoCr LDH through Co doping to enhance electrical conductivity and controlled Cr leaching to introduce cationic vacancies for modulating intermediate binding strength in NiFe LDH.X-ray absorption near-edge structure and extended X-ray absorption fine structure analyses reveal that NiFe-LDH with Co doping and Cr vacancies modulates the Ni oxidation state and local coordination environment,leading to a balanced electronic structure and enhanced structural complexity around the Ni sites.Additionally,these vacancies can trap OH^(-)/H_(2)O species,which can serve as a reservoir for OH^(-) transfer,facilitating the rapid formation of OER intermediates and enhancing catalytic performance at high current densities.As a result,V_(Cr)-NiFeCo LDH achieves 1.6 A cm^(-2)current density at 1.7 V vs.RHE while maintaining stable operation for over 1000 h at 500 mA cm^(-2).Density functional theory(DFT)calculations validate the synergistic effects of Co doping and Cr-induced vacancies on intermediate binding energies and improved OER kinetics.Overall,this work presents a rational design strategy to simultaneously enhance the activity and durability of NiFe-based OER catalysts for their application in high-performance alkaline water electrolysis.展开更多
Artificial photosynthesis of hydrogen peroxide(H_(2)O_(2))from earth-abundant water and oxygen is a sustainable approach,however current photocatalysts suffer from low production rate and solar-to-chemical conversion ...Artificial photosynthesis of hydrogen peroxide(H_(2)O_(2))from earth-abundant water and oxygen is a sustainable approach,however current photocatalysts suffer from low production rate and solar-to-chemical conversion efficiency(<1.5%).Herein,we report that nickelchromium layered double hydroxide with intercalated nitrate(NiCrOOH-NO_(3))and a thickness of~4.4 nm is an efficient photocatalyst,enabling a H_(2)O_(2)production yield of 28.7 mmol g^(-1)h^(-1)under visible light irradiation with3.92%solar-to-chemical conversion efficiency.Experimental and computational studies have revealed an inherent facet-dependent reduction-oxidation reaction behavior and spatial separation of photogenerated electrons and holes.An unexpected role of intercalated nitrate is demonstrated,which promotes excited electron—hole spatial separation and facilitates the electron transfer to oxygen intermediate via delocalization.This work provides understandings in the impact of nanostructure and anion in the design of advanced photocatalysts,paving the way toward practical synthesis of H_(2)O_(2)using fully solar-driven renewable energy.展开更多
High-entropy layered hydroxides(HELHs),an emerging frontier in entropy-stabilized materials derived from layered double hydroxides(LDHs),have captivated attention with their unparalleled tunability,thermodynamic stabi...High-entropy layered hydroxides(HELHs),an emerging frontier in entropy-stabilized materials derived from layered double hydroxides(LDHs),have captivated attention with their unparalleled tunability,thermodynamic stability,and electrochemical performance.The integration of the high-entropy concept into LDHs empowers HELHs to surmount the constraints of conventional materials through compositional diversity,structurally disordered configurations,and synergistic multi-element interactions.This review systematically embarks on their synthesis methodologies,functional mechanisms,and applications in energy conversion/storage and biomedicine.Advanced synthesis strategies,such as plasma-assisted hydrothermal methods,facilitate precise control over HELH architectures while supporting scalable production.HELHs demonstrate superior electrochemical performance in critical reactions,including oxygen evolution reaction,water oxidation,hydrogen evolution,and glucose electrooxidation.Future directions encompass integrating in situ characterization with simulations,leveraging machine learning for composition screening,and expanding HELHs application through interdisciplinary collaborations.This work establishes a comprehensive roadmap for advancing HELHs as next-generation multifunctional platforms for sustainable energy and biomedical technologies.展开更多
NiFe layered double hydroxide(NiFe LDH)has emerged as a promising catalyst for the oxygen evolution reaction(OER);however,its hydrogen evolution reaction(HER)activity remains suboptimal due to unfavorable electronic s...NiFe layered double hydroxide(NiFe LDH)has emerged as a promising catalyst for the oxygen evolution reaction(OER);however,its hydrogen evolution reaction(HER)activity remains suboptimal due to unfavorable electronic structures,particularly the d-electron density of metal sites,which impede water dissociation and lead to poor hydrogen adsorption/desorption capabilities.Herein,we introduce an efficient cooperative d-electron density regulation(CDDR)engineering to comprehensively optimize the delectron density of NiFe LDH by grafting MoO_(x) -modified NiFe LDH nanosheets onto porous nickel particles(PNPs).The PNPs facilitate d-electron density modulation along the edges of the nanosheets,while the MoO_(x) species enable d-electron density modulation across the plane of the nanosheets,thus cooperatively constructing enriched d-electron density in NiFe LDH.Theoretical studies validate the CDDR process and reveal that the enriched d-electron density accelerates water dissociation and optimizes the hydrogen adsorption behavior of NiFe LDH.As a result,the engineered catalyst exhibits significantly improved HER activity,achieving an ultra-low overpotential of 38 mV at 10 mA cm^(-2)in 1 M KOH.Additionally,the CDDR-optimized catalyst also exhibits good OER performance,demonstrating excellent bifunctional performance for overall water splitting in both alkaline freshwater and seawater electrolytes.This work presents a novel CDDR strategy for engineering NiFe LDH into efficient HER catalysts without compromising its OER activity,potentially paving the way for the development of active and robust electrocatalysts for sustainable energy applications.展开更多
A method for the effective in-situ formation of boron-containing Mg-Al layered double hydroxides(LDHs)was developed for boron removal and stabilization.The influence of the B/Al molar ratio and pH on the formation of ...A method for the effective in-situ formation of boron-containing Mg-Al layered double hydroxides(LDHs)was developed for boron removal and stabilization.The influence of the B/Al molar ratio and pH on the formation of Mg-Al-B–LDHs was investigated.Compared with the adsorption method,under a high B/Al ratio,the coprecipitation method increased the boron sorption density from 0.256 to 0.472 of Al.The Toxicity Characteristic Leaching Procedure showed that the boron-coprecipitated LDHs exhibited higher stability than the boron-adsorption LDHs.The synthesized LDH samples were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,and solid-state 11B-NMR.The results showed that boron was effectively incorporated into the LDH structure for the coprecipitation method.Combined with the experimental results,a potential in-situ formation pathway for Mg-Al-B–LDHs was elucidated through density functional theory calculations.The boron tended to directly incorporate into the LDH structure in the coprecipitation method,whereas it was predominantly adsorbed on the LDH surface in the adsorption method.The adsorption energy demonstrated that boron preferentially bonded to Mg^(2+)sites on the surface.The mechanism of boron incorporation in the LDHs for the coprecipitation method involved precipitation of amorphous aluminum hydroxide,layered boehmite transformation,nucleation,and layer stacking.During these processes,boron formed complexes to enhance its stability.Residual boron underwent further reactions with the LDHs,including surface adsorption and ion exchange.These findings provide theoretical insight into the effective removal and long-term immobilization of boron in landfill leachate self-remediation processes.展开更多
Owing to its excellent eco-friendliness and facile water elution properties,aluminum-based lithium adsorbents have attracted a surge of interest for selectively extracting Li^(+)from Salt Lake brines,which account for...Owing to its excellent eco-friendliness and facile water elution properties,aluminum-based lithium adsorbents have attracted a surge of interest for selectively extracting Li^(+)from Salt Lake brines,which account for more than 60%of the global lithium resources.However,structural collapse,facile deactivation during desorption process,and ultra-low actual adsorption capacity limit its further large-scale application,particularly in low-grade sulfate-type brines.Herein,considering its advantages,limitations,and structural features,the structural collapse of the aluminum-based lithium adsorbent was effectively suppressed by the in situ intercalation of VO_(3)^(-)and V_(2)O_(7)^(4-)into the interlayer of[LiAl_(2)(OH)_(6)]^(+).Evidently,the initial adsorption capacity andα_(Mg)^(Li)of as-configured adsorbents powder are 14.96 mg g^(-1) and 192.42 in real sulfate-type West Taijinar Salt Lake brines following NaCl salts removal with 800 mg L^(-1) Li^(+)and 9.56 g L^(-1) SO_(4)^(2-).Furthermore,the initial and retained adsorption capacities of these novel adsorbents granulate in brines after 100 adsorption/desorption cycles are 26.68 and 10.36 mg g^(-1),respectively,which are almost 10 times higher than those of industrially utilized products.Based on experiments and density functional theory calculations,the process and mechanism of anion intercalation control were preliminarily elucidated.Furthermore,research findings indicate that intercalated anions can influence not only interlayer interactions but also the backbone strength of LDH-type adsorbents.This work significantly overcomes the major utilization challenges of aluminum-based lithium adsorbents,thereby enabling the high-efficiency and stable extraction of Li^(+)from low-grade brines,including sulfate-type brines.展开更多
Amorphous two-dimensional transition metal oxide/(oxy)hydroxide(2D TMO/TMHO)nanomaterials(NMs)have the properties of both 2D and amorphous materials,displaying outstanding physicochemical qualities.Therefore,they demo...Amorphous two-dimensional transition metal oxide/(oxy)hydroxide(2D TMO/TMHO)nanomaterials(NMs)have the properties of both 2D and amorphous materials,displaying outstanding physicochemical qualities.Therefore,they demonstrate considerable promise for use in electrocatalytic water splitting applications.Here,the primary amorphization strategies for achieving the 2D TMO/TMHO NMs are comprehensively reviewed,including low-temperature reaction,rapid reaction,exchange/doping effect,ligand modulation,and interfacial energy confinement.By integrating these strategies with various physicochemical synthesis methods,it is feasible to control the amorphization of TMO/TMHO NMs while maintaining the distinctive benefits of their 2D structures.Furthermore,it delves into the structural advantages of amorphous 2D TMO/TMHO NMs in electrocatalytic water splitting,particularly emphasizing recent advancements in enhancing their electrocatalytic performance through interface engineering.The challenges and potential future directions for the precise synthesis and practical application of amorphous 2D TMO/TMHO NMs are also provided.This review aims to establish a theoretical foundation and offer experimental instructions for developing effective and enduring electrocatalysts for water splitting.展开更多
Rationally design the morphology and structure of electroactive nanomaterials is an effective approach to enhance the performance of aqueous batteries.Herein,we co-engineered the hollow architecture and interlayer spa...Rationally design the morphology and structure of electroactive nanomaterials is an effective approach to enhance the performance of aqueous batteries.Herein,we co-engineered the hollow architecture and interlayer spacing of layered double hydroxides(LDH)to achieve high electrochemical activity.The hierarchical hollow LDH was prepared from bimetallic zeolitic imidazolate frameworks(ZIF)by a facile cation exchange strategy.Zn and Cu elements were selected as the second metals incorporated in Co-ZIF.The characteristics of the corresponding derivatives were studied.Besides,the transformation mechanism of CoZn-ZIF into nanosheet-assembled hollow Co Zn Ni LDH(denoted as CoZnNi-OH)was systematically investigated.Importantly,the interlayer spacing of CoZnNi-OH expands due to Zn^(2+)incorporation.The prepared CoZnNi-OH offers large surface area,exposed active sites,and rapid mass transfer/diffusion rate,which lead to a significant enhancement in the specific capacitance,rate performance,and cycle stability of CoZnNi-OH electrode.In addition,the aqueous alkaline CoZnNi-OH//Zn showed a maximum energy density/power density of 0.924 m Wh/cm^(2),8.479 m W/cm^(2).This work not only raises an insightful strategy for regulating the morphology and interlayer spacing of LDH,but also provides a reference of designing hollow nickel-based nanomaterials for aqueous batteries.展开更多
CoFe bimetallic hydroxides(CoFe BMHs)find wide applications as excellent catalysts in the field of water splitting.However,no study has systematically investigated the influence of the morphologies of CoFe BMHs on cat...CoFe bimetallic hydroxides(CoFe BMHs)find wide applications as excellent catalysts in the field of water splitting.However,no study has systematically investigated the influence of the morphologies of CoFe BMHs on catalyst performance.In this study,CoFe BMH nanoflowers(CoFe BMH NFs),CoFe BMH nanosheets(CoFe BMH NSHs),CoFe BMH nanorods(CoFe BMH NRs),and CoFe BMH nanospheres(CoFe BMH NSPs)were prepared on nickel foam via a hydrothermal method.CoFe BMH NSHs exhibited the most beneficial catalytic activity.At a current density of 100 mA·cm^(-2),its overpotential for oxygen evolution reaction(OER)was 282 mV,and the overall water splitting voltage was 2.05 V.The double-layer charging capacitance(Cdl)value of CoFe BMH NSHs was the largest in CoFe BMHs,which proves that CoFe BMH NSHs have the largest active area.Furthermore,the active site in the OER process was metal oxyhydroxide(MOOH)through in situ Raman characterization,and the generation of the active substance was an irreversible process.This work provides important insights into the design of catalyst morphologies and offers valuable guidelines for the enhancement of the performance of other catalysts.展开更多
Rationally regulating the inevitable dynamic evolution of the catalyst surface structure towards high efficiency for water electrolysis remains a significant challenge.Here,the ternary cobalt-iron-chromium double hydr...Rationally regulating the inevitable dynamic evolution of the catalyst surface structure towards high efficiency for water electrolysis remains a significant challenge.Here,the ternary cobalt-iron-chromium double hydroxide(DH)was synthesized on nickel foam as a monolithic catalytic electrode(CoFeCr-DH/NF)for the oxygen evolution reaction(OER)via a simple electrodeposition technique.The optimized Co_(0.7)Fe_(0.3)Cr-DH/NF electrode exhibited remarkable catalytic activity and stability.The overpotential at the current density of 100 mA cm^(-2) is only 281 mV,far exceeding those of other monolithic catalytic electrodes.Furthermore,we elucidated the variations in the valence states of metals during the OER process and found the electrochemical oxidation of Co^(2+)to Co^(3+)and leaching of Cr.Importantly,Cr-leaching can induce surface reconstruction,which not only optimizes the surface electronic structure to enhance the intrinsic activity but also increases the surface irregularity to enlarge the electrochemically active surface area,thereby significantly improving the OER performance.Theoretical calculations revealed that OER preferentially occurred at the adjacent Cr-leached Co sites and confirmed that the Cr-leached trimetallic CoFeCr-DH performs an outstanding OER performance.展开更多
Selective oxidation of amines to imines through electrocatalysis is an attractive and efficient way for the chemical industry to produce nitrile compounds,but it is limited by the difficulty of designing efficient cat...Selective oxidation of amines to imines through electrocatalysis is an attractive and efficient way for the chemical industry to produce nitrile compounds,but it is limited by the difficulty of designing efficient catalysts and lack of understanding the mechanism of catalysis.Herein,we demonstrate a novel strategy by generation of oxyhydroxide layers on two-dimensional iron-doped layered nickel phosphorus trisulfides(Ni1-xFexPS_(3))during the oxidation of benzylamine(BA).In-depth structural and surface chemical characterizations during the electrocatalytic process combined with theoretical calculations reveal that Ni(1-x)FexPS_(3) undergoes surface reconstruction under alkaline conditions to form the metal oxyhydroxide/phosphorus trichalcogenide(NiFeOOH/Ni1-xFexPS_(3))heterostructure.Interestingly,the generated heterointerface facilitates BA oxidation with a low onset potential of 1.39 V and Faradaic efficiency of 53%for benzonitrile(BN)synthesis.Theoretical calculations further indicate that the as-formed NiFeOOH/Ni1-xFexPS_(3) heterostructure could offer optimum free energy for BA adsorption and BN desorption,resulting in promising BN synthesis.展开更多
Remaining largely under-appreciated, a majority of metal ion sorbents are limited in their target selectivity. In this work, a 3D sulfide intercalated NiFe-layered double hydroxide (NFL-S) hierarchical sorbent has bee...Remaining largely under-appreciated, a majority of metal ion sorbents are limited in their target selectivity. In this work, a 3D sulfide intercalated NiFe-layered double hydroxide (NFL-S) hierarchical sorbent has been synthesized for selective heavy metal removal. The intercalation of sulfurated groups in the interlayer of the layered double hydroxide (LDH) nanosheets endows NFL-S as a selective heavy metal ion filter;the selectivity of NFL-S for heavy metals is in the order of Pb^2+> Cu^2+≥ Zn^2+> Cd^2+> Mn^2+, and NFL-S has high kd values for Pb2+(~10^6 mL/g) and Cu2+(~10^5 mL/g). Scanning electron microscopy. X-ray photoelectron spectroscopy and powder X-ray diffraction were used to analyze the composition of the as-prepared nanoadsorbent. The selective adsorption behavior was systematically studied using batch experiments, and the performance was evaluated through kinetic and isotherm studies. Moreover, the adsorption mechanism of heavy metals by NFL-S through surface complexation was also investigated, which shows great potential for water decontamination.展开更多
Catalytic oxidation is regarded as one of the most promising strategies for volatile organic compounds(VOCs)purification.Mixed metal oxides(MMOs),after topological transformation using layered double hydroxides(LDHs)a...Catalytic oxidation is regarded as one of the most promising strategies for volatile organic compounds(VOCs)purification.Mixed metal oxides(MMOs),after topological transformation using layered double hydroxides(LDHs)as precursors,are extensively used as catalysts for VOCs oxidation due to their uniformity advantage.This review summarizes the developments in the LDH-derived VOCs heterogeneous catalytic oxidation over the last 10 years.Particularly,it addresses the VOCs abatement performance over MMO,noble metal/MMO,core-shell structured MMO,and integral MMO film catalysts originating from LDHs.Moreover,it highlights the water vapor effect and oxidation mechanism.This review indicates that LDH-based catalysts are a category of important VOCs oxidation materials.展开更多
The research of superior water oxidation electrodes is essential for the green energy in the form of hydrogen by way of electrolytic water splitting, and still remains challenging. Based upon dealloying foam, Fe-Ni hy...The research of superior water oxidation electrodes is essential for the green energy in the form of hydrogen by way of electrolytic water splitting, and still remains challenging. Based upon dealloying foam, Fe-Ni hydroxide nanosheets network structure is designed on the surface of Fe-Ni alloy foam. The ratio of Ni/Fe elements was adjusted to realize the optimal catalytic activities for oxygen evolution reaction（OER） and hydrogen evolution reaction（HER）. The obtained electrode of Fe-Ni hydroxide nanosheets/Fe-Ni alloy foam-60% Fe（FN LDH/FNF-60, 60 is the percentage of Fe content） possess low overpotential of 261 mV to reach 10 mA/cm;, small Tafel slope（85.5 mV/dec）, and superior long-term stability（remaining 10 mA/cm;for over 14 h without attenuation） toward OER in 1.0 mol/L KOH.Moreover, an alkaline water electrolyzer is constructed with the FN LDH/FNF-60 as anode and Ni（OH）;/Fe-Ni alloy foam-25% Fe(Ni（OH）;/FNF-25) as cathode, which displays superior electrolytic performance（affording 10 mA/cm;at 1.62 V） and lasting durability.展开更多
Layered double hydroxide(LDH) has been widely developed in the field of corrosion and protection in recent years based on its unique characteristics including anion capacity, anion exchange ability, structure memory e...Layered double hydroxide(LDH) has been widely developed in the field of corrosion and protection in recent years based on its unique characteristics including anion capacity, anion exchange ability, structure memory effect, and barrier resistance. This paper comprehensively reviews recent work on the preparations, properties of LDH in the forms of powder and film and their applications in different environments in corrosion and protection. Some novel perspectives are also proposed at the end of the review for future research in corrosion and protection field.展开更多
Alkali metal hydroxide and hydride composite systems contain both protic （H bonded with O） and hydridic hydrogen. The interaction of these two types of hydrides produces hydrogen. The enthalpy of dehydrogenation inc...Alkali metal hydroxide and hydride composite systems contain both protic （H bonded with O） and hydridic hydrogen. The interaction of these two types of hydrides produces hydrogen. The enthalpy of dehydrogenation increased with the increase of atomic number of alkali metals, i.e., -23 kJ/molnz for LiOH-LiH, 55.34 kJ/moln： for NaOH-NaH and 222 kJ/molH2 for KOH-KH. These thermodynamic calculation results were consistent with our experimental results. H2 was released from LiOH-LiH system during ball milling. The dehydrogenation temperature of NaOH-NaH system was about 150 ℃; whereas KOH and KH did not interact with each other during the heating process. Instead, KH decomposed by itself. In these three systems, NaOH-NaH was the only reversible hydrogen storage system, the enthalpy of dehydrogenation was about 55.65 kJ/molHz, and the corresponding entropy was ca. 101.23 J/（molHz .K）, so the temperature for releasing 1.0 bar H2 was as high as 518 ℃, showing unfavorable thermodynamic properties. The activation energy for hydrogen desorption of NaOH-NaH was found to be 57.87 kJ/mol, showing good kinetic properties.展开更多
Mg2+in MgAl-layered double hydroxides nanoparticles was substituted with different divalent transition metal ions(MAl-LDHs,M:Mg2+,Cu2+,Ni2+,Co2+,and Mn2+)via a facile method to be used as antibacterial agents.The phas...Mg2+in MgAl-layered double hydroxides nanoparticles was substituted with different divalent transition metal ions(MAl-LDHs,M:Mg2+,Cu2+,Ni2+,Co2+,and Mn2+)via a facile method to be used as antibacterial agents.The phase structural and morphological characterizations of MAl-LDHs were investigated by XRD,FTIR spectroscopy and TEM.The results have shown that all of MAl-LDHs had typical layered structures except MnAl-LDH which contained Mn304 phases.Particular morphology of MnAl-LDH with ellipsoids,spherical and rod-like structure and CuAl-LDH with rod-like shape existed.IC50(the concentrations providing 50%antibacterial activity)values of CuAl-LDH,NiAl-LDH,CoAl-LDH,and MnAlLDH in broth dilution tests were^800-1500μg/mL.Dosages of CuAl-LDH,CoAl-LDH,and MnAl-LDH with>10 mm inhibition zone in disk diffusion tests were^150-300μg/disk.Antibacterial mechanism of MAl-LDHs may be attributed to the synergistic factors including effected surroundings,surface interactions,morphology of particles,ROS and metal ions.The results indicate a facile method to synthesis LDHs based effective antibacterial agents with the potential application in the area of water treatment and antibacterial coating.展开更多
This study aimed to fabricate new and effective material for the efficiency of phosphate adsorption.Two types of adsorbent materials,the zirconium hydroxides embedded in pomegranate peel(Zr/Peel)and zirconium-lanthanu...This study aimed to fabricate new and effective material for the efficiency of phosphate adsorption.Two types of adsorbent materials,the zirconium hydroxides embedded in pomegranate peel(Zr/Peel)and zirconium-lanthanum hydroxides embedded in pomegranate peel(Zr-La/Peel)were developed.Scanning electronic microscopy(SEM),x-ray photoelectron spectroscopy(XPS)and x-ray diffraction(XRD)were evaluated to give insight into the physicochemical properties of these adsorbents.Zr-La/Peel exceeded the adsorption efficiency of Zr/Peel adsorbents in batch adsorption experiments at the same pH level.The peel as a host can strive to have a strong"shielding effect"to increase the steadiness of the entrenched Zr and La elements.La and Zr are hydroxide metals that emit many hydrogen ions during the hydrolysis reaction,which contribute to protonation and electrostatic attraction.The highest adsorption capacity of La-Zr/Peel for phosphate was calculated to be40.21 mg/g,and pseudo second-order equation is very well fitted for kinetic adsorption.Phosphate adsorption efficiency was reduced by an increase of pH.With the background of coexisting Cl-,little effect on adsorption efficiency was observed,while adsorption capacities were reduced by almost 20-30%with the coexistence of SO42-,NO3-and humic acid(HA).展开更多
Precipitation is often used for the preparation of La(OH)_(3)with precipitants of liquid alkali and ammonia.To solve the problems of high cost and wastewater pollution caused by common precipitants,the active MgO synt...Precipitation is often used for the preparation of La(OH)_(3)with precipitants of liquid alkali and ammonia.To solve the problems of high cost and wastewater pollution caused by common precipitants,the active MgO synthesized by pyrolysis was used as the precipitant to prepare La(OH)_(3).The species distribution of LaCl_(3)and LaCl_(3)-MgCl_(2)mixed system solution was calculated,and the kinetic analysis of the precipi-tation process was carried out to confirm the key factors influencing the precipitation of La(OH)_(3).The results show that La(OH)_(3)with D_(50)of 5.57μm,a specific surface area of 25.70 m^(2)/g,a rod-like shape,and MgO content of 0.044 wt%,was successfully prepared by adding active MgO.The precipitation ratio of La reaches 99.92%.The La(OH)_(3)precipitation is controlled by the diffusion process.The activity of MgO has a significant influence on MgO content in the precipitate.The preparation of La(OH)_(3)by active MgO provides a potential way for an eco-friendly preparation method of rare earth.展开更多
基金the support from the National Key Research and Development Program of China(2023YFB4005000)the Joint Fund of Liaoning Binhai Laboratory(LBLF-2023-04)+3 种基金Dalian Science and Technology Talent Innovation Support Plan(2022RY09)Innovation Research Fund of Dalian Institute of Chemical Physics(DICP I202318)National Natural Science Foundation of China(22478384)the UK EPSRC(EP/W03784X/1)。
文摘Large-scale hydrogen production via water electrolysis faces a freshwater shortage.Direct seawater electrolysis offers a solution but encounters new challenges.Herein,we report a feasible strategy to both prevent metal hydroxides deposition and boost the hydrogen evolution reaction by adding a chelating agent,EDTA-Na_(4),that chelates with Mg^(2+)/Ca^(2+),thus inhibiting their deposition and gathering them near the cathode surface,resulting in breaking the ordered hydrogen bond networks of interfacial water and reducing the activation energy of water dissociation.Furthermore,hydrolysis of–COO^(-) also promoted water dissociation to produce more active*H and*OH near the electrode surface that in turn serves as a diffusion medium for*OH,accelerating mass transfer and enabling seawater electrolysis to exhibit a stable performance,which operates continuously at 100 mA cm^(-2)@2.20 V and 200 mA cm^(-2)@2.58 V for 400 h in the symmetric electrolyzer and 500 mA cm^(-2)@2.29 V for over 500 h in the asymmetric electrolyzer.This study provides a new perspective to address the issues of stable and scalable direct seawater electrolysis for practical green hydrogen production.
基金supported by the Natural Science Foundation of China Grant No.52272289 and 5240223,and JSPS(Japan Society for the Promotion of Science)of Grant No.22K19088,23H00313,24H02202,and 24H02205。
文摘NiFe-layered double hydroxides(NiFe-LDHs)are among the most promising earth-abundant electrocatalysts for the oxygen evolution reaction(OER)in alkaline media.However,their practical application is hindered by intrinsic activity limitations and poor stability,primarily due to the asymmetric adsorption of oxygen intermediates.To overcome this,the binding strength must be synergistically tuned to a moderate level to optimize catalytic performance.Here,we engineered NiFeCoCr LDH through Co doping to enhance electrical conductivity and controlled Cr leaching to introduce cationic vacancies for modulating intermediate binding strength in NiFe LDH.X-ray absorption near-edge structure and extended X-ray absorption fine structure analyses reveal that NiFe-LDH with Co doping and Cr vacancies modulates the Ni oxidation state and local coordination environment,leading to a balanced electronic structure and enhanced structural complexity around the Ni sites.Additionally,these vacancies can trap OH^(-)/H_(2)O species,which can serve as a reservoir for OH^(-) transfer,facilitating the rapid formation of OER intermediates and enhancing catalytic performance at high current densities.As a result,V_(Cr)-NiFeCo LDH achieves 1.6 A cm^(-2)current density at 1.7 V vs.RHE while maintaining stable operation for over 1000 h at 500 mA cm^(-2).Density functional theory(DFT)calculations validate the synergistic effects of Co doping and Cr-induced vacancies on intermediate binding energies and improved OER kinetics.Overall,this work presents a rational design strategy to simultaneously enhance the activity and durability of NiFe-based OER catalysts for their application in high-performance alkaline water electrolysis.
基金support from the National Natural Science Foundation of China(NSFC 21905092,22475072 and 22075085)the Fundamental Research Funds for the Central Universities+1 种基金supported by the Shanghai Frontiers Science Center of Molecule Intelligent SynthesesEast China Normal University Multifunctional Platform for Innovation(004)。
文摘Artificial photosynthesis of hydrogen peroxide(H_(2)O_(2))from earth-abundant water and oxygen is a sustainable approach,however current photocatalysts suffer from low production rate and solar-to-chemical conversion efficiency(<1.5%).Herein,we report that nickelchromium layered double hydroxide with intercalated nitrate(NiCrOOH-NO_(3))and a thickness of~4.4 nm is an efficient photocatalyst,enabling a H_(2)O_(2)production yield of 28.7 mmol g^(-1)h^(-1)under visible light irradiation with3.92%solar-to-chemical conversion efficiency.Experimental and computational studies have revealed an inherent facet-dependent reduction-oxidation reaction behavior and spatial separation of photogenerated electrons and holes.An unexpected role of intercalated nitrate is demonstrated,which promotes excited electron—hole spatial separation and facilitates the electron transfer to oxygen intermediate via delocalization.This work provides understandings in the impact of nanostructure and anion in the design of advanced photocatalysts,paving the way toward practical synthesis of H_(2)O_(2)using fully solar-driven renewable energy.
基金the financial support by Advanced Materials-National Science and Technology Major Project(2024ZD0607400)the National Natural Science Foundation of China(No.52402305)+4 种基金the high-level innovation and entrepreneurship talent project of Qinchuangyuan(No.QCYRCXM-2023-084)the Postdoctoral Fellowship Program of CPSF under Grant Number GZB20230570 and 2024M752552Key projects of Shaanxi Province,China(2023GXLH-001)Natural Science Basic Research Program of Shaanxi(Program No.2024JCYBQN-0494,No.2022TD-27)the State Key Laboratory for Electrical Insulation and Power Equipment(No.EIPE23125)。
文摘High-entropy layered hydroxides(HELHs),an emerging frontier in entropy-stabilized materials derived from layered double hydroxides(LDHs),have captivated attention with their unparalleled tunability,thermodynamic stability,and electrochemical performance.The integration of the high-entropy concept into LDHs empowers HELHs to surmount the constraints of conventional materials through compositional diversity,structurally disordered configurations,and synergistic multi-element interactions.This review systematically embarks on their synthesis methodologies,functional mechanisms,and applications in energy conversion/storage and biomedicine.Advanced synthesis strategies,such as plasma-assisted hydrothermal methods,facilitate precise control over HELH architectures while supporting scalable production.HELHs demonstrate superior electrochemical performance in critical reactions,including oxygen evolution reaction,water oxidation,hydrogen evolution,and glucose electrooxidation.Future directions encompass integrating in situ characterization with simulations,leveraging machine learning for composition screening,and expanding HELHs application through interdisciplinary collaborations.This work establishes a comprehensive roadmap for advancing HELHs as next-generation multifunctional platforms for sustainable energy and biomedical technologies.
基金financially supported from the National Key Research and Development Program of China(2022YFB3803600)the National Natural Science Foundation of China(52301272,22309168,12564025,and 52472205)+7 种基金the Fundamental Research Funds for the Central Universities(CCNU25ZH006)the National College Student Innovation and Entrepreneurship Training Project(202510513082)the Research Program of HBNU(2025X082 and2025Y145)the Foundation of Hubei Key Laboratory of Photoelectric Materials and Devices(PMD202404)the General Program of Open Project of the State Key Laboratory of Precision Welding and Joining of Materials Structures(MSWJ-25M-18)the Key Research Project of Hubei Provincial Department of Education(No.D20252503)the Key Project of Hubei Provincial Natural Science Foundation of China(2025AFD002)the Foundation of National Laboratory of Solid State Microstructures(M37087)。
文摘NiFe layered double hydroxide(NiFe LDH)has emerged as a promising catalyst for the oxygen evolution reaction(OER);however,its hydrogen evolution reaction(HER)activity remains suboptimal due to unfavorable electronic structures,particularly the d-electron density of metal sites,which impede water dissociation and lead to poor hydrogen adsorption/desorption capabilities.Herein,we introduce an efficient cooperative d-electron density regulation(CDDR)engineering to comprehensively optimize the delectron density of NiFe LDH by grafting MoO_(x) -modified NiFe LDH nanosheets onto porous nickel particles(PNPs).The PNPs facilitate d-electron density modulation along the edges of the nanosheets,while the MoO_(x) species enable d-electron density modulation across the plane of the nanosheets,thus cooperatively constructing enriched d-electron density in NiFe LDH.Theoretical studies validate the CDDR process and reveal that the enriched d-electron density accelerates water dissociation and optimizes the hydrogen adsorption behavior of NiFe LDH.As a result,the engineered catalyst exhibits significantly improved HER activity,achieving an ultra-low overpotential of 38 mV at 10 mA cm^(-2)in 1 M KOH.Additionally,the CDDR-optimized catalyst also exhibits good OER performance,demonstrating excellent bifunctional performance for overall water splitting in both alkaline freshwater and seawater electrolytes.This work presents a novel CDDR strategy for engineering NiFe LDH into efficient HER catalysts without compromising its OER activity,potentially paving the way for the development of active and robust electrocatalysts for sustainable energy applications.
基金supported by the research equipment (Nos. G1006,G1010 and G1018) shared in MEXT Project for promoting public utilization of advanced research infrastructure (Program for supporting construction of core facilities)(No. JPMXS0440500023)financial support of the China Scholarship Council.
文摘A method for the effective in-situ formation of boron-containing Mg-Al layered double hydroxides(LDHs)was developed for boron removal and stabilization.The influence of the B/Al molar ratio and pH on the formation of Mg-Al-B–LDHs was investigated.Compared with the adsorption method,under a high B/Al ratio,the coprecipitation method increased the boron sorption density from 0.256 to 0.472 of Al.The Toxicity Characteristic Leaching Procedure showed that the boron-coprecipitated LDHs exhibited higher stability than the boron-adsorption LDHs.The synthesized LDH samples were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,and solid-state 11B-NMR.The results showed that boron was effectively incorporated into the LDH structure for the coprecipitation method.Combined with the experimental results,a potential in-situ formation pathway for Mg-Al-B–LDHs was elucidated through density functional theory calculations.The boron tended to directly incorporate into the LDH structure in the coprecipitation method,whereas it was predominantly adsorbed on the LDH surface in the adsorption method.The adsorption energy demonstrated that boron preferentially bonded to Mg^(2+)sites on the surface.The mechanism of boron incorporation in the LDHs for the coprecipitation method involved precipitation of amorphous aluminum hydroxide,layered boehmite transformation,nucleation,and layer stacking.During these processes,boron formed complexes to enhance its stability.Residual boron underwent further reactions with the LDHs,including surface adsorption and ion exchange.These findings provide theoretical insight into the effective removal and long-term immobilization of boron in landfill leachate self-remediation processes.
基金supported by the Sichuan Provincial Department of Science and Technology Project (2025YFHZ0271).
文摘Owing to its excellent eco-friendliness and facile water elution properties,aluminum-based lithium adsorbents have attracted a surge of interest for selectively extracting Li^(+)from Salt Lake brines,which account for more than 60%of the global lithium resources.However,structural collapse,facile deactivation during desorption process,and ultra-low actual adsorption capacity limit its further large-scale application,particularly in low-grade sulfate-type brines.Herein,considering its advantages,limitations,and structural features,the structural collapse of the aluminum-based lithium adsorbent was effectively suppressed by the in situ intercalation of VO_(3)^(-)and V_(2)O_(7)^(4-)into the interlayer of[LiAl_(2)(OH)_(6)]^(+).Evidently,the initial adsorption capacity andα_(Mg)^(Li)of as-configured adsorbents powder are 14.96 mg g^(-1) and 192.42 in real sulfate-type West Taijinar Salt Lake brines following NaCl salts removal with 800 mg L^(-1) Li^(+)and 9.56 g L^(-1) SO_(4)^(2-).Furthermore,the initial and retained adsorption capacities of these novel adsorbents granulate in brines after 100 adsorption/desorption cycles are 26.68 and 10.36 mg g^(-1),respectively,which are almost 10 times higher than those of industrially utilized products.Based on experiments and density functional theory calculations,the process and mechanism of anion intercalation control were preliminarily elucidated.Furthermore,research findings indicate that intercalated anions can influence not only interlayer interactions but also the backbone strength of LDH-type adsorbents.This work significantly overcomes the major utilization challenges of aluminum-based lithium adsorbents,thereby enabling the high-efficiency and stable extraction of Li^(+)from low-grade brines,including sulfate-type brines.
基金supported by the National Key Research and Development Program of China(No.2018YFA0703700)the National Natural Science Foundation of China(No.12034002)the Interdisciplinary Research Project for Young Teachers of USTB(Fundamental Research Funds for the Central Universities,No.FRF-IDRY-23-033)。
文摘Amorphous two-dimensional transition metal oxide/(oxy)hydroxide(2D TMO/TMHO)nanomaterials(NMs)have the properties of both 2D and amorphous materials,displaying outstanding physicochemical qualities.Therefore,they demonstrate considerable promise for use in electrocatalytic water splitting applications.Here,the primary amorphization strategies for achieving the 2D TMO/TMHO NMs are comprehensively reviewed,including low-temperature reaction,rapid reaction,exchange/doping effect,ligand modulation,and interfacial energy confinement.By integrating these strategies with various physicochemical synthesis methods,it is feasible to control the amorphization of TMO/TMHO NMs while maintaining the distinctive benefits of their 2D structures.Furthermore,it delves into the structural advantages of amorphous 2D TMO/TMHO NMs in electrocatalytic water splitting,particularly emphasizing recent advancements in enhancing their electrocatalytic performance through interface engineering.The challenges and potential future directions for the precise synthesis and practical application of amorphous 2D TMO/TMHO NMs are also provided.This review aims to establish a theoretical foundation and offer experimental instructions for developing effective and enduring electrocatalysts for water splitting.
基金supported by the National Natural Science Foundation of China(Nos.52371240,U1904215)Natural Science Foundation of Jiangsu Province(No.BK20200044)Changjiang scholars’program of the Ministry of Education(No.Q2018270)。
文摘Rationally design the morphology and structure of electroactive nanomaterials is an effective approach to enhance the performance of aqueous batteries.Herein,we co-engineered the hollow architecture and interlayer spacing of layered double hydroxides(LDH)to achieve high electrochemical activity.The hierarchical hollow LDH was prepared from bimetallic zeolitic imidazolate frameworks(ZIF)by a facile cation exchange strategy.Zn and Cu elements were selected as the second metals incorporated in Co-ZIF.The characteristics of the corresponding derivatives were studied.Besides,the transformation mechanism of CoZn-ZIF into nanosheet-assembled hollow Co Zn Ni LDH(denoted as CoZnNi-OH)was systematically investigated.Importantly,the interlayer spacing of CoZnNi-OH expands due to Zn^(2+)incorporation.The prepared CoZnNi-OH offers large surface area,exposed active sites,and rapid mass transfer/diffusion rate,which lead to a significant enhancement in the specific capacitance,rate performance,and cycle stability of CoZnNi-OH electrode.In addition,the aqueous alkaline CoZnNi-OH//Zn showed a maximum energy density/power density of 0.924 m Wh/cm^(2),8.479 m W/cm^(2).This work not only raises an insightful strategy for regulating the morphology and interlayer spacing of LDH,but also provides a reference of designing hollow nickel-based nanomaterials for aqueous batteries.
基金supported by the National Science Fund for Distinguished Young Scholars(No.52025041)the National Natural Science Foundation of China(Nos.52474319,52250091,U2341267,and 52450003)+1 种基金the Fundamental Research Funds for the Central Universities(No.FRF-TP-20-02C2)supported by the Interdisciplinary Research Project for Young Teachers of USTB,China(Fundamental Research Funds for the Central Universities)(No.FRF-IDRY-GD23-003).
文摘CoFe bimetallic hydroxides(CoFe BMHs)find wide applications as excellent catalysts in the field of water splitting.However,no study has systematically investigated the influence of the morphologies of CoFe BMHs on catalyst performance.In this study,CoFe BMH nanoflowers(CoFe BMH NFs),CoFe BMH nanosheets(CoFe BMH NSHs),CoFe BMH nanorods(CoFe BMH NRs),and CoFe BMH nanospheres(CoFe BMH NSPs)were prepared on nickel foam via a hydrothermal method.CoFe BMH NSHs exhibited the most beneficial catalytic activity.At a current density of 100 mA·cm^(-2),its overpotential for oxygen evolution reaction(OER)was 282 mV,and the overall water splitting voltage was 2.05 V.The double-layer charging capacitance(Cdl)value of CoFe BMH NSHs was the largest in CoFe BMHs,which proves that CoFe BMH NSHs have the largest active area.Furthermore,the active site in the OER process was metal oxyhydroxide(MOOH)through in situ Raman characterization,and the generation of the active substance was an irreversible process.This work provides important insights into the design of catalyst morphologies and offers valuable guidelines for the enhancement of the performance of other catalysts.
基金financially supported by the National Natural Science Foundation of China(Nos.22162026 and 22263011)the Shaanxi Provincial Science and Technology Plan Project(No.2020JQ-792)+2 种基金the Youth Science and Technology Star Project of Shaanxi Province(No.2023KJXX-053)the Science and Technology Plan Project of Yulin Government(Nos.CXY-2022-82,CXY-2022-186,and 2023-CXY-213)the Training Program of Innovation and Entrepreneurship for Undergraduates(No.S202310719113).
文摘Rationally regulating the inevitable dynamic evolution of the catalyst surface structure towards high efficiency for water electrolysis remains a significant challenge.Here,the ternary cobalt-iron-chromium double hydroxide(DH)was synthesized on nickel foam as a monolithic catalytic electrode(CoFeCr-DH/NF)for the oxygen evolution reaction(OER)via a simple electrodeposition technique.The optimized Co_(0.7)Fe_(0.3)Cr-DH/NF electrode exhibited remarkable catalytic activity and stability.The overpotential at the current density of 100 mA cm^(-2) is only 281 mV,far exceeding those of other monolithic catalytic electrodes.Furthermore,we elucidated the variations in the valence states of metals during the OER process and found the electrochemical oxidation of Co^(2+)to Co^(3+)and leaching of Cr.Importantly,Cr-leaching can induce surface reconstruction,which not only optimizes the surface electronic structure to enhance the intrinsic activity but also increases the surface irregularity to enlarge the electrochemically active surface area,thereby significantly improving the OER performance.Theoretical calculations revealed that OER preferentially occurred at the adjacent Cr-leached Co sites and confirmed that the Cr-leached trimetallic CoFeCr-DH performs an outstanding OER performance.
基金National Natural Science Foundation of China,Grant/Award Number:22179029Fundamental Research Funds for the Central Universities,Grant/Award Number:buctrc202324+2 种基金Young Elite Scientists Sponsorship Program by BAST,Grant/Award Number:BYESS2023093Ministero dell'Istruzione,dell'Universitàe della Ricerca,Grant/Award Number:2022FNL89YKempestiftelserna。
文摘Selective oxidation of amines to imines through electrocatalysis is an attractive and efficient way for the chemical industry to produce nitrile compounds,but it is limited by the difficulty of designing efficient catalysts and lack of understanding the mechanism of catalysis.Herein,we demonstrate a novel strategy by generation of oxyhydroxide layers on two-dimensional iron-doped layered nickel phosphorus trisulfides(Ni1-xFexPS_(3))during the oxidation of benzylamine(BA).In-depth structural and surface chemical characterizations during the electrocatalytic process combined with theoretical calculations reveal that Ni(1-x)FexPS_(3) undergoes surface reconstruction under alkaline conditions to form the metal oxyhydroxide/phosphorus trichalcogenide(NiFeOOH/Ni1-xFexPS_(3))heterostructure.Interestingly,the generated heterointerface facilitates BA oxidation with a low onset potential of 1.39 V and Faradaic efficiency of 53%for benzonitrile(BN)synthesis.Theoretical calculations further indicate that the as-formed NiFeOOH/Ni1-xFexPS_(3) heterostructure could offer optimum free energy for BA adsorption and BN desorption,resulting in promising BN synthesis.
基金financially supported by the National Natural Science Foundation of China (No. 21675127)the Shaanxi Provincial Science Fund for Distinguished Young Scholars (No. 2018JC-011)
文摘Remaining largely under-appreciated, a majority of metal ion sorbents are limited in their target selectivity. In this work, a 3D sulfide intercalated NiFe-layered double hydroxide (NFL-S) hierarchical sorbent has been synthesized for selective heavy metal removal. The intercalation of sulfurated groups in the interlayer of the layered double hydroxide (LDH) nanosheets endows NFL-S as a selective heavy metal ion filter;the selectivity of NFL-S for heavy metals is in the order of Pb^2+> Cu^2+≥ Zn^2+> Cd^2+> Mn^2+, and NFL-S has high kd values for Pb2+(~10^6 mL/g) and Cu2+(~10^5 mL/g). Scanning electron microscopy. X-ray photoelectron spectroscopy and powder X-ray diffraction were used to analyze the composition of the as-prepared nanoadsorbent. The selective adsorption behavior was systematically studied using batch experiments, and the performance was evaluated through kinetic and isotherm studies. Moreover, the adsorption mechanism of heavy metals by NFL-S through surface complexation was also investigated, which shows great potential for water decontamination.
基金supported by the National Key R&D Program of China(2017YFC0211503,2016YFC0207100)the Strategic Priority Research Program(A)of the Chinese Academy of Sciences(XDA23030300)+2 种基金the National Natural Science Foundation of China(21401200,51672273)the Open Research Fund of State Key Laboratory of Multi-phase Complex Systems(MPCS-2017-D-06)the Young Talent Project of the Center for Excellence in Regional Atmospheric Environment,CAS(CERAE201805)~~
文摘Catalytic oxidation is regarded as one of the most promising strategies for volatile organic compounds(VOCs)purification.Mixed metal oxides(MMOs),after topological transformation using layered double hydroxides(LDHs)as precursors,are extensively used as catalysts for VOCs oxidation due to their uniformity advantage.This review summarizes the developments in the LDH-derived VOCs heterogeneous catalytic oxidation over the last 10 years.Particularly,it addresses the VOCs abatement performance over MMO,noble metal/MMO,core-shell structured MMO,and integral MMO film catalysts originating from LDHs.Moreover,it highlights the water vapor effect and oxidation mechanism.This review indicates that LDH-based catalysts are a category of important VOCs oxidation materials.
基金supported by the Science and Technology Planning Project of Guangdong Province,China(No.2017B090916002)Tip-top Scientific and Technical Innovative Youth Talents of Guangdong Special Support Program(No.2016TQ03N541)+2 种基金Guangdong Natural Science Funds for Distinguished Young Scholar(No.2017B030306001)the National Natural Science Foundation of China(No.91745203)Guangdong Innovative and Entrepreneurial Research Team Program(No.2014ZT05N200)
文摘The research of superior water oxidation electrodes is essential for the green energy in the form of hydrogen by way of electrolytic water splitting, and still remains challenging. Based upon dealloying foam, Fe-Ni hydroxide nanosheets network structure is designed on the surface of Fe-Ni alloy foam. The ratio of Ni/Fe elements was adjusted to realize the optimal catalytic activities for oxygen evolution reaction（OER） and hydrogen evolution reaction（HER）. The obtained electrode of Fe-Ni hydroxide nanosheets/Fe-Ni alloy foam-60% Fe（FN LDH/FNF-60, 60 is the percentage of Fe content） possess low overpotential of 261 mV to reach 10 mA/cm;, small Tafel slope（85.5 mV/dec）, and superior long-term stability（remaining 10 mA/cm;for over 14 h without attenuation） toward OER in 1.0 mol/L KOH.Moreover, an alkaline water electrolyzer is constructed with the FN LDH/FNF-60 as anode and Ni（OH）;/Fe-Ni alloy foam-25% Fe(Ni（OH）;/FNF-25) as cathode, which displays superior electrolytic performance（affording 10 mA/cm;at 1.62 V） and lasting durability.
基金financially supported by the State Key Project of Research and Development (No. 2016YFC1100300)the National Natural Science Foundation of China (No. 21203158, 21773199, and 21621091)。
文摘Layered double hydroxide(LDH) has been widely developed in the field of corrosion and protection in recent years based on its unique characteristics including anion capacity, anion exchange ability, structure memory effect, and barrier resistance. This paper comprehensively reviews recent work on the preparations, properties of LDH in the forms of powder and film and their applications in different environments in corrosion and protection. Some novel perspectives are also proposed at the end of the review for future research in corrosion and protection field.
基金supported by the National Natural Science Foundation of China(51301161)973 Project(2010CB631304)the Project of National Natural Science Funds for Distinguished Young Scholar(51225206)
文摘Alkali metal hydroxide and hydride composite systems contain both protic （H bonded with O） and hydridic hydrogen. The interaction of these two types of hydrides produces hydrogen. The enthalpy of dehydrogenation increased with the increase of atomic number of alkali metals, i.e., -23 kJ/molnz for LiOH-LiH, 55.34 kJ/moln： for NaOH-NaH and 222 kJ/molH2 for KOH-KH. These thermodynamic calculation results were consistent with our experimental results. H2 was released from LiOH-LiH system during ball milling. The dehydrogenation temperature of NaOH-NaH system was about 150 ℃; whereas KOH and KH did not interact with each other during the heating process. Instead, KH decomposed by itself. In these three systems, NaOH-NaH was the only reversible hydrogen storage system, the enthalpy of dehydrogenation was about 55.65 kJ/molHz, and the corresponding entropy was ca. 101.23 J/（molHz .K）, so the temperature for releasing 1.0 bar H2 was as high as 518 ℃, showing unfavorable thermodynamic properties. The activation energy for hydrogen desorption of NaOH-NaH was found to be 57.87 kJ/mol, showing good kinetic properties.
基金financially supported by Advance Queensland Research Fellowship Project and Chinese Scholarship Council(CSC)。
文摘Mg2+in MgAl-layered double hydroxides nanoparticles was substituted with different divalent transition metal ions(MAl-LDHs,M:Mg2+,Cu2+,Ni2+,Co2+,and Mn2+)via a facile method to be used as antibacterial agents.The phase structural and morphological characterizations of MAl-LDHs were investigated by XRD,FTIR spectroscopy and TEM.The results have shown that all of MAl-LDHs had typical layered structures except MnAl-LDH which contained Mn304 phases.Particular morphology of MnAl-LDH with ellipsoids,spherical and rod-like structure and CuAl-LDH with rod-like shape existed.IC50(the concentrations providing 50%antibacterial activity)values of CuAl-LDH,NiAl-LDH,CoAl-LDH,and MnAlLDH in broth dilution tests were^800-1500μg/mL.Dosages of CuAl-LDH,CoAl-LDH,and MnAl-LDH with>10 mm inhibition zone in disk diffusion tests were^150-300μg/disk.Antibacterial mechanism of MAl-LDHs may be attributed to the synergistic factors including effected surroundings,surface interactions,morphology of particles,ROS and metal ions.The results indicate a facile method to synthesis LDHs based effective antibacterial agents with the potential application in the area of water treatment and antibacterial coating.
基金supported by the National Natural Science Foundation of China(No.51978384)Tai Shan Scholar Foundation(No.ts20151003)
文摘This study aimed to fabricate new and effective material for the efficiency of phosphate adsorption.Two types of adsorbent materials,the zirconium hydroxides embedded in pomegranate peel(Zr/Peel)and zirconium-lanthanum hydroxides embedded in pomegranate peel(Zr-La/Peel)were developed.Scanning electronic microscopy(SEM),x-ray photoelectron spectroscopy(XPS)and x-ray diffraction(XRD)were evaluated to give insight into the physicochemical properties of these adsorbents.Zr-La/Peel exceeded the adsorption efficiency of Zr/Peel adsorbents in batch adsorption experiments at the same pH level.The peel as a host can strive to have a strong"shielding effect"to increase the steadiness of the entrenched Zr and La elements.La and Zr are hydroxide metals that emit many hydrogen ions during the hydrolysis reaction,which contribute to protonation and electrostatic attraction.The highest adsorption capacity of La-Zr/Peel for phosphate was calculated to be40.21 mg/g,and pseudo second-order equation is very well fitted for kinetic adsorption.Phosphate adsorption efficiency was reduced by an increase of pH.With the background of coexisting Cl-,little effect on adsorption efficiency was observed,while adsorption capacities were reduced by almost 20-30%with the coexistence of SO42-,NO3-and humic acid(HA).
基金the National Key Research and Development Program of China(2022YFB3504503)the National Natural Science Foundation of China(52274355)the Gansu Province Science and Technology Major Special Project,China(22ZD6GD061).
文摘Precipitation is often used for the preparation of La(OH)_(3)with precipitants of liquid alkali and ammonia.To solve the problems of high cost and wastewater pollution caused by common precipitants,the active MgO synthesized by pyrolysis was used as the precipitant to prepare La(OH)_(3).The species distribution of LaCl_(3)and LaCl_(3)-MgCl_(2)mixed system solution was calculated,and the kinetic analysis of the precipi-tation process was carried out to confirm the key factors influencing the precipitation of La(OH)_(3).The results show that La(OH)_(3)with D_(50)of 5.57μm,a specific surface area of 25.70 m^(2)/g,a rod-like shape,and MgO content of 0.044 wt%,was successfully prepared by adding active MgO.The precipitation ratio of La reaches 99.92%.The La(OH)_(3)precipitation is controlled by the diffusion process.The activity of MgO has a significant influence on MgO content in the precipitate.The preparation of La(OH)_(3)by active MgO provides a potential way for an eco-friendly preparation method of rare earth.
