Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability cau...Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution.展开更多
Strategy of anchoring alloy nanoparticles made up of the efficient catalytic element(e.g.,Ni,Fe)on dodecyl sulfate(DS^(-))-intercalated NiFe layered double hydroxides(DS^(-)-NiFe LDH)obtained by a convenient one-step ...Strategy of anchoring alloy nanoparticles made up of the efficient catalytic element(e.g.,Ni,Fe)on dodecyl sulfate(DS^(-))-intercalated NiFe layered double hydroxides(DS^(-)-NiFe LDH)obtained by a convenient one-step hydrothermal coprecipitation method for essentially enhancing oxygen evolution reaction(OER)performance was proposed.The results of structural characterization indicate Pt_(2)FeNi alloy nanoparticles evenly distribute on the surface of DS^(-)-NiFe LDH.The sizes of the Pt_(2)FeNi nanoparticles,closely related to their OER performance,could be wellcontrolled by adjusting the amount of H;PtCl;addition.The composite structure of as-prepared product was stable during processes of synthesis,exfoliation,self-assembly,and subsequent electrocatalytic OER.Rigorous electrochemical test proving the contributing catalytic active sites was located at the interface between Pt_(2)FeNi and DS^(-)-NiFe LDH,and the Ni and Fe were the major active elements while O atoms are adsorption sites.The formation of Pt_(2)FeNi nanoparticles could greatly prompt the reduction of Tafel slope.The best-performing Pt_(2)FeNi/DS^(-)-NiFe LDH with a Pt content of 0.98 wt%achieved low overpotential of 204 mV at 10 mA cm^(-2)and 262 mV at 50 mA cm^(-2).This work provides a convenient and effective strategy to create additional active sites for enhancing OER performance of NiFe LDH and make contribution to its wide application.展开更多
Compared with noble metal catalyst, Co3O4-based electrocatalysts have attracted considerable interesting as low-cost alternatives for oxygen evolution reaction (OER). However, the poor electrocatalytic activity still ...Compared with noble metal catalyst, Co3O4-based electrocatalysts have attracted considerable interesting as low-cost alternatives for oxygen evolution reaction (OER). However, the poor electrocatalytic activity still remains a huge challenge. Herein, we demonstrate a feasible approach through oxidation of CoFe layered double hydroxide (CoFe-LDH) to synthesize Fe-doped Co3O4@C nanopmrticles with size of about 30-50 nm. As OER catalyst, the as-synthesized Fe-doped Co3O4@C nanoparticles exhibited superior OER performance with a small overpotential of 260 mV at the current density of 20 mA cm^-2, a small Tafel slope of 70 mV dec^-1 and long-term durability (there was no obviously OER current density degradation for 100 h) in alkaline solution. The present work opens a new avenue to the exploration of cost-effective and excellent electrocatalysts based on transition metal oxide materials to substitute precious metal materials for water splitting.展开更多
Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(...Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(C_(2)O_(4))_(3)]^(3-)into NiFe LDHs by intercalation engineering to promote surface reconstruction achieves an advanced oxygen evolution reaction(OER)activity.In view of the weak electronegativity of Cr^(3+) in[Cr(C_(2)O_(4))_(3)]^(3-),the intercalation of[Cr(C_(2)O_(4))_(3)]^(3-)is expected to result in an electron-rich structure of Fe sites in NiFe LDHs,and higher valence state of Ni can be formed with the charge transfer between Fe and Ni.The optimized electronic structure of NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs with more active Ni^(3+) species and the expedited dynamic generation of Ni^(3+) (Fe)OOH phase during the OER process contributed to its excellent catalytic property,revealed by in situ X-ray absorption spectroscopy,Raman spectroscopy,and quasi-in situ X-ray photoelectron spectroscopy.With the modulated electronic structure of metal sites,NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs exhibited promoted OER property with a lower overpotential of 236 mV at the current density of 10 mA cm^(-2).This work illustrates the intercalation of conjugated anion to dynamically construct desired Ni^(3+) sites with the optimal electronic environment for improved OER electrocatalysis.展开更多
In order to obtain the bio-moleculel LDHs nanocomposites having regular crystal structure,three nanocomposites of layered double hydroxides and polyoxyethylene sulfates were prepared by ion-exchange method.TEM analysi...In order to obtain the bio-moleculel LDHs nanocomposites having regular crystal structure,three nanocomposites of layered double hydroxides and polyoxyethylene sulfates were prepared by ion-exchange method.TEM analysis reveals that the monodisperse rigid sphere of approximately 200 nm in diameter could be gotten when the intergallery anion was PEGS-400.Such monodisperse nanoparticle could be used as a promising precursor for preparing bio-moleculel LDHs nanocomposites.展开更多
A positive Mg-Al-nitrate layered double hydroxides (LDHs) has been synthesized using a non-steady coprecipitation method. The shape, size, chemical composition, electrical property and anion exchange property of the ...A positive Mg-Al-nitrate layered double hydroxides (LDHs) has been synthesized using a non-steady coprecipitation method. The shape, size, chemical composition, electrical property and anion exchange property of the positive nanoparticle were studied by SEM, XRD, FTIR, chemical analysis, spectroanalysis and measuring of electrophoretic mobilities. Preliminary results show the positive nanoparticle is a promising precursor of polymer/LDHs nanocomposite.展开更多
Novel magnetic Fe3O4@C@MgAl-layerecl double-hydroxide（LDH） nanoparticles have been successfully prepared by the chemical self-assembly methods.The properties of surface functional groups,crystal structure,magnetism ...Novel magnetic Fe3O4@C@MgAl-layerecl double-hydroxide（LDH） nanoparticles have been successfully prepared by the chemical self-assembly methods.The properties of surface functional groups,crystal structure,magnetism and surface morphology of magnetic nanoparticles were characterized by Fourier transform infrared spectroscopy（FT-IR）,X-ray diffraction（XRD）,thermal gravity-differential thermal gravity（TG-DTG）,scanning electron microscopy（SEM）,and transmission electron microscopy（TEM）.The adsorption studies of the novel adsorbent in removing heavy metals Cr（Ⅵ） from waste water showed that the maximum absorption amount of Cr（Ⅵ） was 152.0 mg/g at 40℃ and pH 6.0.The excellent adsorption capacity of the Fe3O4@C@MgAl-LDH nano-absorbents plus their easy separation,environmentally friendly composition and reusability makes them more suitable adsorbents for the removal of metal ions from waste water.展开更多
旨在预防猫、犬诱导的过敏反应,本研究将猫主要变应原Fel d 1与犬主要变应原Can f 1融合原核表达,纯化制备了rFel d 1-Can f 1融合变应原。将层状双氢氧化物(layered double hydroxides,LDH)与rFel d 1-Can f 1混合,制备LDH-rFel d 1-Ca...旨在预防猫、犬诱导的过敏反应,本研究将猫主要变应原Fel d 1与犬主要变应原Can f 1融合原核表达,纯化制备了rFel d 1-Can f 1融合变应原。将层状双氢氧化物(layered double hydroxides,LDH)与rFel d 1-Can f 1混合,制备LDH-rFel d 1-Can f 1,皮下注射法免疫BALB/c小鼠,随后利用rFel d 1-Can f 1融合变应原诱导过敏小鼠模型,通过检测小鼠应激性过敏反应的体温变化、耳朵点刺试验、肺部组织切片HE染色、血清IgE水平等指标评价LDH-rFel d 1-Can f 1对猫犬诱发过敏反应的预防效果。研究表明,LDH与rFel d 1-Can f 1质量比为7∶1时,LDH可以完全吸附rFel d 1-Can f 1融合蛋白。LDH-rFel d 1-Can f 1可以有效缓解应激性过敏反应引起的小鼠体温下降,显著减少过敏导致的染料渗透面积。肺部组织切片HE染色结果显示,LDH-rFel d 1-Can f 1可以缓解过敏引起的炎症细胞浸润。此外,LDH-rFel d 1-Can f 1免疫后可以诱导小鼠产生较高水平IgG,这为开发抑制宠物猫犬诱发过敏反应的疫苗奠定基础。展开更多
Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water splitting.To address these challenges,researchers are increasingly exploring ...Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water splitting.To address these challenges,researchers are increasingly exploring binder-free electrocatalytic integratedelectrodes (IEs) as an alternative to conventional powder-based electrode preparation methods,for the former is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of electrocatalysts.Herein,we demonstrate a laser-inducedhydrothermal reaction (LIHR) technique to grow NiMoO4nanosheets on nickel foam,which is then calcined under H2/Ar mixed gases to prepare the IE IE-NiMo-LR.This electrode exhibits superior hydrogen evolution reaction performance,requiring overpotentials of 59,116 and143 mV to achieve current densities of 100,500 and 1000 mA·cm-2.During the 350 h chronopotentiometry test at current densities of 100 and 500 m A·cm-2,the overpotentialremains essentially unchanged.In addition,NiFe-layered double hydroxide grown on Ni foam is also fabricated with the same LIHR method and coupled with IE-NiMo-IR to achieve water splitting.This combination exhibits excellent durability under industrial current density.The energy consumption and production efficiency of the LIHR method are systematicallycompared with the conventional hydrothermal method.The LIHR method significantly improves the production rate by over 19 times,while consuming only 27.78%of the total energy required by conventional hydrothermal methods to achieve the same production.展开更多
为了提高海藻酸钠(SA)对疏水性农药的负载量和释药缓释作用,将其与月桂醇通过偶联酯化反应进行疏水改性,对改性后的海藻酸钠进行红外光谱、核磁共振表征分析,结果证明月桂醇侧链成功接枝到海藻酸钠分子骨架上。将月桂醇改性海藻酸钠(DA...为了提高海藻酸钠(SA)对疏水性农药的负载量和释药缓释作用,将其与月桂醇通过偶联酯化反应进行疏水改性,对改性后的海藻酸钠进行红外光谱、核磁共振表征分析,结果证明月桂醇侧链成功接枝到海藻酸钠分子骨架上。将月桂醇改性海藻酸钠(DA)和十六烷基三甲基溴化铵(CTAB)与层状双金属氢氧化物(LDH)纳米颗粒进行复配,其Zeta电位分别为+44.9 m V和-33.2 m V,同时其粒径分别增大到93.3 nm和659.8 nm。结果表明带负电的月桂醇改性海藻酸钠吸附在层状双金属氢氧化物颗粒表面可以阻碍颗粒间的相互聚集,在分散体系中表现出了良好的稳定性能。高速剪切下制备稳定Pickering乳液,对疏水性农药氯氟氰菊酯进行了释药试验,表明改性后的海藻酸钠与LDH颗粒制备Pickering乳液对氯氟氰菊酯具有较好的药物缓释作用。展开更多
基金support from the Free Exploration Project of Frontier Technology for Laoshan Laboratory(No.16-02)the National Natural Science Foundation of China(Nos.22072015 and 21927811)。
文摘Electrocatalytic hydrogen production from seawater holds enormous promise for clean energy generation.Nevertheless,the direct electrolysis of seawater encounters significant challenges due to poor anodic stability caused by detrimental chlorine chemistry.Herein,we present our recent discovery that the incorporation of Ce into Ni Fe layered double hydroxide nanosheet array on Ni foam(Ce-Ni Fe LDH/NF)emerges as a robust electrocatalyst for seawater oxidation.During the seawater oxidation process,CeO_(2)is generated,effectively repelling Cl^(-)and inhibiting the formation of Cl O-,resulting in a notable enhancement in the oxidation activity and stability of alkaline seawater.The prepared Ce-Ni Fe LDH/NF requires only overpotential of 390 m V to achieve the current density of 1 A cm^(-2),while maintaining long-term stability for 500 h,outperforming the performance of Ni Fe LDH/NF(430 m V,150 h)by a significant margin.This study highlights the effectiveness of a Ce-doping strategy in augmenting the activity and stability of materials based on Ni Fe LDH in seawater electrolysis for oxygen evolution.
基金the financial support by the National Natural Science Foundation of China(51874357,51872333,U20A20123)Innovative Research Group of Hunan Provincial Natural Science Foundation of China(2019JJ10006)support from Shenghua Scholar Program of Central South University.R.M.acknowledges support from JSPS KAKENNHI(18H03869)。
文摘Strategy of anchoring alloy nanoparticles made up of the efficient catalytic element(e.g.,Ni,Fe)on dodecyl sulfate(DS^(-))-intercalated NiFe layered double hydroxides(DS^(-)-NiFe LDH)obtained by a convenient one-step hydrothermal coprecipitation method for essentially enhancing oxygen evolution reaction(OER)performance was proposed.The results of structural characterization indicate Pt_(2)FeNi alloy nanoparticles evenly distribute on the surface of DS^(-)-NiFe LDH.The sizes of the Pt_(2)FeNi nanoparticles,closely related to their OER performance,could be wellcontrolled by adjusting the amount of H;PtCl;addition.The composite structure of as-prepared product was stable during processes of synthesis,exfoliation,self-assembly,and subsequent electrocatalytic OER.Rigorous electrochemical test proving the contributing catalytic active sites was located at the interface between Pt_(2)FeNi and DS^(-)-NiFe LDH,and the Ni and Fe were the major active elements while O atoms are adsorption sites.The formation of Pt_(2)FeNi nanoparticles could greatly prompt the reduction of Tafel slope.The best-performing Pt_(2)FeNi/DS^(-)-NiFe LDH with a Pt content of 0.98 wt%achieved low overpotential of 204 mV at 10 mA cm^(-2)and 262 mV at 50 mA cm^(-2).This work provides a convenient and effective strategy to create additional active sites for enhancing OER performance of NiFe LDH and make contribution to its wide application.
基金supported by the 973 Program(no.2014CB932104)the National Natural Science Foundation of China(nos:2177060378,U1707603 and 21521005)the Program for Changjiang Scholars,Innovative Research Teams in Universities(no.IRT1205)
文摘Compared with noble metal catalyst, Co3O4-based electrocatalysts have attracted considerable interesting as low-cost alternatives for oxygen evolution reaction (OER). However, the poor electrocatalytic activity still remains a huge challenge. Herein, we demonstrate a feasible approach through oxidation of CoFe layered double hydroxide (CoFe-LDH) to synthesize Fe-doped Co3O4@C nanopmrticles with size of about 30-50 nm. As OER catalyst, the as-synthesized Fe-doped Co3O4@C nanoparticles exhibited superior OER performance with a small overpotential of 260 mV at the current density of 20 mA cm^-2, a small Tafel slope of 70 mV dec^-1 and long-term durability (there was no obviously OER current density degradation for 100 h) in alkaline solution. The present work opens a new avenue to the exploration of cost-effective and excellent electrocatalysts based on transition metal oxide materials to substitute precious metal materials for water splitting.
基金support from the National Natural Science Foundation of China(51402100,21905088,21573066 and U19A2017)the Provincial Natural Science Foundation of Hunan(2020JJ5044,2022JJ10006)。
文摘Rationally manipulating surface reconstruction of catalysts for water oxidation,inducing formation and dynamic accumulation of catalytically active centers still face numerous challenges.Herein,the introduction of[Cr(C_(2)O_(4))_(3)]^(3-)into NiFe LDHs by intercalation engineering to promote surface reconstruction achieves an advanced oxygen evolution reaction(OER)activity.In view of the weak electronegativity of Cr^(3+) in[Cr(C_(2)O_(4))_(3)]^(3-),the intercalation of[Cr(C_(2)O_(4))_(3)]^(3-)is expected to result in an electron-rich structure of Fe sites in NiFe LDHs,and higher valence state of Ni can be formed with the charge transfer between Fe and Ni.The optimized electronic structure of NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs with more active Ni^(3+) species and the expedited dynamic generation of Ni^(3+) (Fe)OOH phase during the OER process contributed to its excellent catalytic property,revealed by in situ X-ray absorption spectroscopy,Raman spectroscopy,and quasi-in situ X-ray photoelectron spectroscopy.With the modulated electronic structure of metal sites,NiFe-[Cr(C_(2)O_(4))_(3)]^(3-)-LDHs exhibited promoted OER property with a lower overpotential of 236 mV at the current density of 10 mA cm^(-2).This work illustrates the intercalation of conjugated anion to dynamically construct desired Ni^(3+) sites with the optimal electronic environment for improved OER electrocatalysis.
文摘In order to obtain the bio-moleculel LDHs nanocomposites having regular crystal structure,three nanocomposites of layered double hydroxides and polyoxyethylene sulfates were prepared by ion-exchange method.TEM analysis reveals that the monodisperse rigid sphere of approximately 200 nm in diameter could be gotten when the intergallery anion was PEGS-400.Such monodisperse nanoparticle could be used as a promising precursor for preparing bio-moleculel LDHs nanocomposites.
文摘A positive Mg-Al-nitrate layered double hydroxides (LDHs) has been synthesized using a non-steady coprecipitation method. The shape, size, chemical composition, electrical property and anion exchange property of the positive nanoparticle were studied by SEM, XRD, FTIR, chemical analysis, spectroanalysis and measuring of electrophoretic mobilities. Preliminary results show the positive nanoparticle is a promising precursor of polymer/LDHs nanocomposite.
基金supported by Scientific Research Starting Project of SWPU(No.2014QH013)Open Fund of state key laboratory of Oil & Gas reservoir geology and exploitation(No.PLN1126)major cultivation project of Sichuan Provincial Department of Education Science and Technology Achievement Transformation(No. 14CZ0005)
文摘Novel magnetic Fe3O4@C@MgAl-layerecl double-hydroxide（LDH） nanoparticles have been successfully prepared by the chemical self-assembly methods.The properties of surface functional groups,crystal structure,magnetism and surface morphology of magnetic nanoparticles were characterized by Fourier transform infrared spectroscopy（FT-IR）,X-ray diffraction（XRD）,thermal gravity-differential thermal gravity（TG-DTG）,scanning electron microscopy（SEM）,and transmission electron microscopy（TEM）.The adsorption studies of the novel adsorbent in removing heavy metals Cr（Ⅵ） from waste water showed that the maximum absorption amount of Cr（Ⅵ） was 152.0 mg/g at 40℃ and pH 6.0.The excellent adsorption capacity of the Fe3O4@C@MgAl-LDH nano-absorbents plus their easy separation,environmentally friendly composition and reusability makes them more suitable adsorbents for the removal of metal ions from waste water.
文摘旨在预防猫、犬诱导的过敏反应,本研究将猫主要变应原Fel d 1与犬主要变应原Can f 1融合原核表达,纯化制备了rFel d 1-Can f 1融合变应原。将层状双氢氧化物(layered double hydroxides,LDH)与rFel d 1-Can f 1混合,制备LDH-rFel d 1-Can f 1,皮下注射法免疫BALB/c小鼠,随后利用rFel d 1-Can f 1融合变应原诱导过敏小鼠模型,通过检测小鼠应激性过敏反应的体温变化、耳朵点刺试验、肺部组织切片HE染色、血清IgE水平等指标评价LDH-rFel d 1-Can f 1对猫犬诱发过敏反应的预防效果。研究表明,LDH与rFel d 1-Can f 1质量比为7∶1时,LDH可以完全吸附rFel d 1-Can f 1融合蛋白。LDH-rFel d 1-Can f 1可以有效缓解应激性过敏反应引起的小鼠体温下降,显著减少过敏导致的染料渗透面积。肺部组织切片HE染色结果显示,LDH-rFel d 1-Can f 1可以缓解过敏引起的炎症细胞浸润。此外,LDH-rFel d 1-Can f 1免疫后可以诱导小鼠产生较高水平IgG,这为开发抑制宠物猫犬诱发过敏反应的疫苗奠定基础。
基金supported by the National Natural Science Foundation of China(21663027,51262028,21261021)the Science and Technology Support Project of Gansu Province(1504GKCA027)+2 种基金the Program for the Young Innovative Talents of Longyuanthe Program for Innovative Research Team(NWNULKQN-15-2)the Undergraduate Academic Innovative Research Team of Northwest Normal University~~
基金financial support from The University of Manchester to cover his PhD tuition fees for him to carry out this workChina National High-end Foreign Experts Recruitment Plan Project (G2023018001L) for partially supporting the work。
文摘Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water splitting.To address these challenges,researchers are increasingly exploring binder-free electrocatalytic integratedelectrodes (IEs) as an alternative to conventional powder-based electrode preparation methods,for the former is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of electrocatalysts.Herein,we demonstrate a laser-inducedhydrothermal reaction (LIHR) technique to grow NiMoO4nanosheets on nickel foam,which is then calcined under H2/Ar mixed gases to prepare the IE IE-NiMo-LR.This electrode exhibits superior hydrogen evolution reaction performance,requiring overpotentials of 59,116 and143 mV to achieve current densities of 100,500 and 1000 mA·cm-2.During the 350 h chronopotentiometry test at current densities of 100 and 500 m A·cm-2,the overpotentialremains essentially unchanged.In addition,NiFe-layered double hydroxide grown on Ni foam is also fabricated with the same LIHR method and coupled with IE-NiMo-IR to achieve water splitting.This combination exhibits excellent durability under industrial current density.The energy consumption and production efficiency of the LIHR method are systematicallycompared with the conventional hydrothermal method.The LIHR method significantly improves the production rate by over 19 times,while consuming only 27.78%of the total energy required by conventional hydrothermal methods to achieve the same production.
基金supported by the Key Program of the National Natural Science Foundation of China(No.22090032,22090030)the Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy(Grant.YLU-DNL Fund 2021001)support from the Dalian Key Laboratory of Electrolysis for Hydrogen Production。
文摘为了提高海藻酸钠(SA)对疏水性农药的负载量和释药缓释作用,将其与月桂醇通过偶联酯化反应进行疏水改性,对改性后的海藻酸钠进行红外光谱、核磁共振表征分析,结果证明月桂醇侧链成功接枝到海藻酸钠分子骨架上。将月桂醇改性海藻酸钠(DA)和十六烷基三甲基溴化铵(CTAB)与层状双金属氢氧化物(LDH)纳米颗粒进行复配,其Zeta电位分别为+44.9 m V和-33.2 m V,同时其粒径分别增大到93.3 nm和659.8 nm。结果表明带负电的月桂醇改性海藻酸钠吸附在层状双金属氢氧化物颗粒表面可以阻碍颗粒间的相互聚集,在分散体系中表现出了良好的稳定性能。高速剪切下制备稳定Pickering乳液,对疏水性农药氯氟氰菊酯进行了释药试验,表明改性后的海藻酸钠与LDH颗粒制备Pickering乳液对氯氟氰菊酯具有较好的药物缓释作用。
