The indiscriminate use and disposal of ciprofloxacin(CIP)have led to its detection in water globally,which pose a huge risk to public health and water environment.Herein,(Zn-Al)LDHs modified 3D reduced graphene oxide ...The indiscriminate use and disposal of ciprofloxacin(CIP)have led to its detection in water globally,which pose a huge risk to public health and water environment.Herein,(Zn-Al)LDHs modified 3D reduced graphene oxide nanocomposite((Zn-Al)LDHs/3D-rGO)was synthesized through a feasible onepot hydrothermal method for CIP removal.The highly distributed(Zn-Al)LDHs flakes on the surface of 3D-rGO endow the resulted(Zn-Al)LDHs/3D-rGO with an excellent adsorption performance for CIP.The adsorption results showed that the adsorption process could be well interpreted by Temkin isothermal model and the pseudo second-order kinetics model.The maximal adsorption capacity of 20.01 mg·g^(-1)for CIP could be achieved under the optimal conditions optimized by response surface methodology(RSM).The inhibitory effect of co-existing ions on CIP adsorption were also discussed.The probable adsorption mechanism might be ascribed toπ-πinteractions,hydrogen bonding,electrostatic,and surface complexation.Regeneration tests showed that the obtained 3D porous material also possessed pronounced recyclability.The obtained(Zn-Al)LDHs/3D-rGO holds a great potential for removal of CIP from actual wastewater.展开更多
The degradation performance of pervious concrete containing TiO_(2)/LDHs-loaded recycled aggregates for NO gas was analyzed using a gas phase catalytic degradation test device,simulating different environmental condit...The degradation performance of pervious concrete containing TiO_(2)/LDHs-loaded recycled aggregates for NO gas was analyzed using a gas phase catalytic degradation test device,simulating different environmental conditions such as load,ambient temperature,and illumination intensity,which provides theoretical support for practical engineering.The experimental results indicate that when the ambient temperature is controlled at 25℃and the illumination intensity is 30 W/m^(2),the sample prepared by soaking recycled aggregates in a 0.8%TiO_(2)/LDHs suspension exhibits the highest photocatalytic degradation rate for NO gas,reaching 72.54%.Further investigation on the influence of environmental temperature reveals that,at 25℃,the maximum photocatalytic degradation rate for NO gas is 72.9%.Moreover,at an illumination intensity of 40 W/m^(2),the maximum photocatalytic degradation rate for NO gas is 87.08%.Additionally,after three repeated photocatalytic tests,the sample demonstrates good stability,with a photocatalytic degradation rate of 58%.The nitrogen content in the eluent obtained from soaking the sample was determined to be 0.0022 mol/L,with a recovery rate of 80%.The adsorption experiment demonstrates that the sample exhibits a favorable adsorption effect on nitrate ions,reaching a maximum of 56.8%.展开更多
Micro-arc oxidation(MAO)flm can only provide common mechanical protection for magnesium(Mg)–lithium(Li)alloys.These alloys are susceptible to severe localized corrosion,if the MAO flm is disrupted.This work reports t...Micro-arc oxidation(MAO)flm can only provide common mechanical protection for magnesium(Mg)–lithium(Li)alloys.These alloys are susceptible to severe localized corrosion,if the MAO flm is disrupted.This work reports the successful hydrothermal preparation of a MgLiAlCe-LDHs@GO flm on a MAO-coated Mg–Li alloy following Ce confnement.The graphene oxide(GO)sheet increased the difusion path of the corrosive media,and the addition of rare-earth cerium ions(Ce^(3+))endowed the flm with a certain self-healing ability,which signifcantly improved the corrosion resistance of the flm,and the corrosion current density(icorr)reached 3.27×10^(−8)A cm^(−2).The synergistic action of GO and Ce^(3+)can achieve long-term corrosion protection for the substrate.The corrosion resistance mechanism of MgLiAlCe-LDHs@GO flm was discussed by the scanning vibration electrode technique(SVET).展开更多
为研究表面有机化层状双羟基复合金属氢氧化物(LDHs)对表面有机化LDHs/橡胶粉复合改性沥青高温性能的影响,文章对基质沥青、橡胶粉改性沥青和表面有机化LDHs/橡胶粉复合改性沥青进行针入度、软化点、延度三大指标与动态剪切流变试验(Dyn...为研究表面有机化层状双羟基复合金属氢氧化物(LDHs)对表面有机化LDHs/橡胶粉复合改性沥青高温性能的影响,文章对基质沥青、橡胶粉改性沥青和表面有机化LDHs/橡胶粉复合改性沥青进行针入度、软化点、延度三大指标与动态剪切流变试验(Dynamic Shear Rheological Test, DSR)和高温力学性能测试。结果表明:加入表面有机化LDHs后,增加了橡胶粉改性沥青的针入度,并提高橡胶粉改性沥青的软化点和延度;在DSR试验中,同一温度条件下,表面有机化LDHs/橡胶粉复合改性沥青的车辙因子显著高于基质沥青和橡胶粉改性沥青。故通过掺加表面有机化LDHs和橡胶粉来提高沥青的耐高温性能具有可行性。In order to study the effect of surface organic Layered Double Hydroxides (LDHs)on the high temperature performance of surface organic LDHs/rubber powder composite modified asphalt, the three indexes of penetration, softening point and ductility of matrix asphalt, rubber powder modified asphalt and surface organic LDHs/rubber powder composite modified asphalt, Dynamic Shear Rheological Test (DSR)and high temperature mechanical properties test were carried out in this paper. The results show that the addition of surface organic LDHs increases the penetration of rubber powder-modified asphalt and improves the softening point and ductility of rubber powder-modified asphalt. In the DSR test, under the same temperature conditions, the rutting factor of the surface organic LDHs/rubber powder composite modified asphalt is significantly higher than that of the matrix asphalt and rubber powder modified asphalt. Therefore, it is feasible to improve the high temperature resistance of asphalt by adding surface organic LDHs and rubber powder.展开更多
Owing to the significant potential of alkalin seawater electrolysis for converting surplus power into eco friendly hydrogen fuel,we developed bifunctional elec trodes that integrate low-crystalline NiFe LDHs and amorp...Owing to the significant potential of alkalin seawater electrolysis for converting surplus power into eco friendly hydrogen fuel,we developed bifunctional elec trodes that integrate low-crystalline NiFe LDHs and amorphous NiFe alloy on a Ni foam(NF)substrate to enhance this process.Driven by the battery-like charac teristics of NiFe LDHs,an anti-corrosive and active oute layer of NiFe^(vac)OOH continuously forms over time in th hybrid on the anode for the oxygen evolution reaction(OER),effectively mitigating powder shedding caused by corrosion induced by multiple anions in seawater.Mean while,the strong bond between the hybrid and the NF substrate maintains intact hybrid coatings to ensure a rel atively high overall conductivity of the electrodes,signif icantly reducing the negative effects of structura degradation during the OER and hydrogen evolution reaction(HER),as well as the accumulation of contami nants on the electrode surfaces.In long-term tests,thes bifunctionalhybridelectrodesmaintained stable performance,even at a high current density o500 mA·cm^(-2).The cell voltage increased by only 88 m V over 1000 h to 1.970 V during saline electrolysis and by103 mV over 500 h to 2.062 V during seawater electroly sis.Hence,this study provides valuable insights into efficient and stable seawater electrolysis using NiFe LDHs–NiFe alloy hybrids.展开更多
A series of Ni-based catalysts were prepared via structural topological transformation from the Ni@Al_(2)O_(3)layered double hydroxides(LDHs)precursors,and applied for the deep catalytic hydrogenation saturation of py...A series of Ni-based catalysts were prepared via structural topological transformation from the Ni@Al_(2)O_(3)layered double hydroxides(LDHs)precursors,and applied for the deep catalytic hydrogenation saturation of pyrene in a high-pressure reactor.The pore structures,active species dispersion,surface morphology,amount and type of acid of the prepared catalysts were characterized by BET,XRD,SEM,TEM,XPS,SEM,NH_(3)-TPD and Py-IR.We studied the influence of physicochemical properties of Ni-based catalysts on the regularity and mechanism of deep hydrogenation of pyrene.Meanwhile,the synergy between Ni and Mo,and the interaction between active metals and support were discussed to further reveal the constitutive relationship during the hydrogenation reaction of pyrene.The results of the evaluation of the catalytic hydrogenation of pyrene show that the as-prepared NiMo mixed metal oxide(MMO)catalyst showed excellent catalytic activity:~95%pyrene conversion,90.12%for the selectivity of deep hydrogenation products(hexahydropyrene,decahydropyrene and hexadecahydropyrene).It was expected that the successfully preparation and utilization of NiMo-MMO catalyst could provide a theoretical basis for the design of this kind of catalysts for deep catalytic hydrogenation of polycyclic aromatic hydrocarbons(PAHs).展开更多
Magnesium(Mg)is a widely used and attractive metal,known for its unique physical and chemical properties,and it has been employed in the manufacture of many practical materials.Layered Double Hydroxides(LDHs),particul...Magnesium(Mg)is a widely used and attractive metal,known for its unique physical and chemical properties,and it has been employed in the manufacture of many practical materials.Layered Double Hydroxides(LDHs),particularly Mg-based LDHs,rank among the most prevalent two-dimensional materials utilized in separation processes,which include adsorption,extraction,and membrane technology.The high popularity of Mg-based LDHs in separation applications can be attributed to their properties,such as excellent hydrophilicity,high surface area,ion exchangeability,and adjustable interlayer space.Currently,polymer membranes play a pivotal role in semi-industrial and industrial separation processes.Consequently,the development of polymer membranes and the mitigation of their limitations have emerged as compelling topics for researchers.Several methods exist to enhance the separation performance and anti-fouling properties of polymer membranes.Among these,incorporating additives into the membrane polymer matrix stands out as a cost-effective,straightforward,readily available,and efficient approach.The use of Mg-based LDHs,either in combination with other materials or as a standalone additive in the polymer membrane matrix,represents a promising strategy to bolster the separation and anti-fouling efficacy of flat sheet mixed matrix polymer membranes.This review highlights Mg-based LDHs as high-potential additives designed to refine flat sheet mixed matrix polymer membranes for applications in wastewater treatment and brackish water desalination.展开更多
Ni-Al-CO3 LDHs/γ-Al2O3 have been prepared using an in-situ synthesis technique. NH3·H2O was chosen as activation agent of Al on the γ-Al2O3 surface as well as precipitant. Ni-Al-CO3 LDHs/γ-Al2O3 was synthesize...Ni-Al-CO3 LDHs/γ-Al2O3 have been prepared using an in-situ synthesis technique. NH3·H2O was chosen as activation agent of Al on the γ-Al2O3 surface as well as precipitant. Ni-Al-CO3 LDHs/γ-Al2O3 was synthesized by controlling the reaction conditions such as temperature, concentration of Ni2+ and initial pH. The crystalline structure, chemical composition and porous structure were characterized by means of XRD, FT-IR, TG-DTA, 27Al MAS-NMR and N2 adsorption-desorption. The resulting sample of Ni-Al-CO3 LDHs/γ-Al2O3 possesses higher specific area and narrower pore distribution, in which Ni-Al-CO3 LDHs are located on the surface of γ-Al2O3 and share the same Al-O bonds with the γ-Al2O3 lattice. Finally a possible structural model was proposed to account for the porous characters of Ni-Al-CO3 LDHs/γ-Al2O3.展开更多
基金support from Basic research project of Education Department of Liaoning Province(LJKZ0256)Special Fund for Basic Scientific Research of Liaoning Province(LJKZSYLUGX027).
文摘The indiscriminate use and disposal of ciprofloxacin(CIP)have led to its detection in water globally,which pose a huge risk to public health and water environment.Herein,(Zn-Al)LDHs modified 3D reduced graphene oxide nanocomposite((Zn-Al)LDHs/3D-rGO)was synthesized through a feasible onepot hydrothermal method for CIP removal.The highly distributed(Zn-Al)LDHs flakes on the surface of 3D-rGO endow the resulted(Zn-Al)LDHs/3D-rGO with an excellent adsorption performance for CIP.The adsorption results showed that the adsorption process could be well interpreted by Temkin isothermal model and the pseudo second-order kinetics model.The maximal adsorption capacity of 20.01 mg·g^(-1)for CIP could be achieved under the optimal conditions optimized by response surface methodology(RSM).The inhibitory effect of co-existing ions on CIP adsorption were also discussed.The probable adsorption mechanism might be ascribed toπ-πinteractions,hydrogen bonding,electrostatic,and surface complexation.Regeneration tests showed that the obtained 3D porous material also possessed pronounced recyclability.The obtained(Zn-Al)LDHs/3D-rGO holds a great potential for removal of CIP from actual wastewater.
基金Funded by the National Natural Science Foundation of China(No.52478281)the Natural Science Foundation of Zhejiang Province(No.LZ22E080003)the Science and Technology Project of Zhejiang Provincial Department of Transport(No.202225)。
文摘The degradation performance of pervious concrete containing TiO_(2)/LDHs-loaded recycled aggregates for NO gas was analyzed using a gas phase catalytic degradation test device,simulating different environmental conditions such as load,ambient temperature,and illumination intensity,which provides theoretical support for practical engineering.The experimental results indicate that when the ambient temperature is controlled at 25℃and the illumination intensity is 30 W/m^(2),the sample prepared by soaking recycled aggregates in a 0.8%TiO_(2)/LDHs suspension exhibits the highest photocatalytic degradation rate for NO gas,reaching 72.54%.Further investigation on the influence of environmental temperature reveals that,at 25℃,the maximum photocatalytic degradation rate for NO gas is 72.9%.Moreover,at an illumination intensity of 40 W/m^(2),the maximum photocatalytic degradation rate for NO gas is 87.08%.Additionally,after three repeated photocatalytic tests,the sample demonstrates good stability,with a photocatalytic degradation rate of 58%.The nitrogen content in the eluent obtained from soaking the sample was determined to be 0.0022 mol/L,with a recovery rate of 80%.The adsorption experiment demonstrates that the sample exhibits a favorable adsorption effect on nitrate ions,reaching a maximum of 56.8%.
基金supported by the National Key R&D Program of China(2021YFB3701100)the National Natural Science Foundation of China(52171101)the Fundamental Research Funds for the Central Universities(2024IAIS-QN009).
文摘Micro-arc oxidation(MAO)flm can only provide common mechanical protection for magnesium(Mg)–lithium(Li)alloys.These alloys are susceptible to severe localized corrosion,if the MAO flm is disrupted.This work reports the successful hydrothermal preparation of a MgLiAlCe-LDHs@GO flm on a MAO-coated Mg–Li alloy following Ce confnement.The graphene oxide(GO)sheet increased the difusion path of the corrosive media,and the addition of rare-earth cerium ions(Ce^(3+))endowed the flm with a certain self-healing ability,which signifcantly improved the corrosion resistance of the flm,and the corrosion current density(icorr)reached 3.27×10^(−8)A cm^(−2).The synergistic action of GO and Ce^(3+)can achieve long-term corrosion protection for the substrate.The corrosion resistance mechanism of MgLiAlCe-LDHs@GO flm was discussed by the scanning vibration electrode technique(SVET).
文摘为研究表面有机化层状双羟基复合金属氢氧化物(LDHs)对表面有机化LDHs/橡胶粉复合改性沥青高温性能的影响,文章对基质沥青、橡胶粉改性沥青和表面有机化LDHs/橡胶粉复合改性沥青进行针入度、软化点、延度三大指标与动态剪切流变试验(Dynamic Shear Rheological Test, DSR)和高温力学性能测试。结果表明:加入表面有机化LDHs后,增加了橡胶粉改性沥青的针入度,并提高橡胶粉改性沥青的软化点和延度;在DSR试验中,同一温度条件下,表面有机化LDHs/橡胶粉复合改性沥青的车辙因子显著高于基质沥青和橡胶粉改性沥青。故通过掺加表面有机化LDHs和橡胶粉来提高沥青的耐高温性能具有可行性。In order to study the effect of surface organic Layered Double Hydroxides (LDHs)on the high temperature performance of surface organic LDHs/rubber powder composite modified asphalt, the three indexes of penetration, softening point and ductility of matrix asphalt, rubber powder modified asphalt and surface organic LDHs/rubber powder composite modified asphalt, Dynamic Shear Rheological Test (DSR)and high temperature mechanical properties test were carried out in this paper. The results show that the addition of surface organic LDHs increases the penetration of rubber powder-modified asphalt and improves the softening point and ductility of rubber powder-modified asphalt. In the DSR test, under the same temperature conditions, the rutting factor of the surface organic LDHs/rubber powder composite modified asphalt is significantly higher than that of the matrix asphalt and rubber powder modified asphalt. Therefore, it is feasible to improve the high temperature resistance of asphalt by adding surface organic LDHs and rubber powder.
基金supported by the National Natural Science Foundation of China(No.22209054)the Natural Science Foundation of Hunan Province(Nos.2023JJ30017 and 2023JJ30030)the Natural Science Foundation of Changsha(No.kq2208223)。
文摘Owing to the significant potential of alkalin seawater electrolysis for converting surplus power into eco friendly hydrogen fuel,we developed bifunctional elec trodes that integrate low-crystalline NiFe LDHs and amorphous NiFe alloy on a Ni foam(NF)substrate to enhance this process.Driven by the battery-like charac teristics of NiFe LDHs,an anti-corrosive and active oute layer of NiFe^(vac)OOH continuously forms over time in th hybrid on the anode for the oxygen evolution reaction(OER),effectively mitigating powder shedding caused by corrosion induced by multiple anions in seawater.Mean while,the strong bond between the hybrid and the NF substrate maintains intact hybrid coatings to ensure a rel atively high overall conductivity of the electrodes,signif icantly reducing the negative effects of structura degradation during the OER and hydrogen evolution reaction(HER),as well as the accumulation of contami nants on the electrode surfaces.In long-term tests,thes bifunctionalhybridelectrodesmaintained stable performance,even at a high current density o500 mA·cm^(-2).The cell voltage increased by only 88 m V over 1000 h to 1.970 V during saline electrolysis and by103 mV over 500 h to 2.062 V during seawater electroly sis.Hence,this study provides valuable insights into efficient and stable seawater electrolysis using NiFe LDHs–NiFe alloy hybrids.
基金supported by the National Natural Science Foundation of China(21536009)Science and Technology Plan Projects of Shaanxi Province(2017ZDCXL-GY-10-03)+1 种基金National Natural Science Foundation of China(22008198)the Special Scientific Research Plan Project of Education Ministry of Shaanxi Province,China(19JK0854).
文摘A series of Ni-based catalysts were prepared via structural topological transformation from the Ni@Al_(2)O_(3)layered double hydroxides(LDHs)precursors,and applied for the deep catalytic hydrogenation saturation of pyrene in a high-pressure reactor.The pore structures,active species dispersion,surface morphology,amount and type of acid of the prepared catalysts were characterized by BET,XRD,SEM,TEM,XPS,SEM,NH_(3)-TPD and Py-IR.We studied the influence of physicochemical properties of Ni-based catalysts on the regularity and mechanism of deep hydrogenation of pyrene.Meanwhile,the synergy between Ni and Mo,and the interaction between active metals and support were discussed to further reveal the constitutive relationship during the hydrogenation reaction of pyrene.The results of the evaluation of the catalytic hydrogenation of pyrene show that the as-prepared NiMo mixed metal oxide(MMO)catalyst showed excellent catalytic activity:~95%pyrene conversion,90.12%for the selectivity of deep hydrogenation products(hexahydropyrene,decahydropyrene and hexadecahydropyrene).It was expected that the successfully preparation and utilization of NiMo-MMO catalyst could provide a theoretical basis for the design of this kind of catalysts for deep catalytic hydrogenation of polycyclic aromatic hydrocarbons(PAHs).
文摘Magnesium(Mg)is a widely used and attractive metal,known for its unique physical and chemical properties,and it has been employed in the manufacture of many practical materials.Layered Double Hydroxides(LDHs),particularly Mg-based LDHs,rank among the most prevalent two-dimensional materials utilized in separation processes,which include adsorption,extraction,and membrane technology.The high popularity of Mg-based LDHs in separation applications can be attributed to their properties,such as excellent hydrophilicity,high surface area,ion exchangeability,and adjustable interlayer space.Currently,polymer membranes play a pivotal role in semi-industrial and industrial separation processes.Consequently,the development of polymer membranes and the mitigation of their limitations have emerged as compelling topics for researchers.Several methods exist to enhance the separation performance and anti-fouling properties of polymer membranes.Among these,incorporating additives into the membrane polymer matrix stands out as a cost-effective,straightforward,readily available,and efficient approach.The use of Mg-based LDHs,either in combination with other materials or as a standalone additive in the polymer membrane matrix,represents a promising strategy to bolster the separation and anti-fouling efficacy of flat sheet mixed matrix polymer membranes.This review highlights Mg-based LDHs as high-potential additives designed to refine flat sheet mixed matrix polymer membranes for applications in wastewater treatment and brackish water desalination.
文摘Ni-Al-CO3 LDHs/γ-Al2O3 have been prepared using an in-situ synthesis technique. NH3·H2O was chosen as activation agent of Al on the γ-Al2O3 surface as well as precipitant. Ni-Al-CO3 LDHs/γ-Al2O3 was synthesized by controlling the reaction conditions such as temperature, concentration of Ni2+ and initial pH. The crystalline structure, chemical composition and porous structure were characterized by means of XRD, FT-IR, TG-DTA, 27Al MAS-NMR and N2 adsorption-desorption. The resulting sample of Ni-Al-CO3 LDHs/γ-Al2O3 possesses higher specific area and narrower pore distribution, in which Ni-Al-CO3 LDHs are located on the surface of γ-Al2O3 and share the same Al-O bonds with the γ-Al2O3 lattice. Finally a possible structural model was proposed to account for the porous characters of Ni-Al-CO3 LDHs/γ-Al2O3.
