The modified zinc phosphate conversion coatings(ZPC) were formed on hot-dip galvanized(HDG) steel when 1.0 g/L sodium molybdate were added in a traditional zinc phosphate solution. The growth performance and corrosion...The modified zinc phosphate conversion coatings(ZPC) were formed on hot-dip galvanized(HDG) steel when 1.0 g/L sodium molybdate were added in a traditional zinc phosphate solution. The growth performance and corrosion resistance of the modified ZPC were investigated by SEM, open circuit potential(OCP), mass gain, potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) measurements and compared with those of the traditional ZPC. The results show that if sodium molybdate is added in a traditional zinc phosphate solution, the nucleation of zinc phosphate crystals is increased obviously; zinc phosphate crystals are changed from bulky acicular to fine flake and a more compact ZPC is obtained. Moreover, the mass gain and coverage of the modified ZPC are also boosted. The corrosion resistance of ZPC is increased with an increase in coverage, and thus the corrosion protection ability of the modified ZPC for HDG steel is more outstanding than that of the traditional ZPC.展开更多
The phosphated hot-dip galvanized(HDG) sheets were post-sealed with sodium molybdate solution to improve the corrosion resistance of phosphate coatings. The morphology,chemical composition and corrosion resistance of ...The phosphated hot-dip galvanized(HDG) sheets were post-sealed with sodium molybdate solution to improve the corrosion resistance of phosphate coatings. The morphology,chemical composition and corrosion resistance of the coatings were investigated using scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),Tafel polarization measurements and neutral salt spray(NSS) tests,and were compared with those of the single coatings. The results show that post-sealing the phosphated HDG steel with molybdate solution,the pores among the zinc phosphate crystals are sealed with molybdate films containing Zn,P,O and Mo,and the continuous composite coatings are formed. The suppression of both the anodic and the cathodic processes of zinc corrosion on the samples are enhanced significantly. The synergistic corrosion protection effect of the single phosphate coatings and molybdate films for zinc is evident. The corrosion resistance of the composite coatings increases with phosphating time up to 300 s.展开更多
Polyaniline stannic molybdate—an organic-inorganic composite material, was prepared via sol-gel mixing of organic polymer polyaniline into matrices of inorganic precipitate of stannicmolybdate. The composite material...Polyaniline stannic molybdate—an organic-inorganic composite material, was prepared via sol-gel mixing of organic polymer polyaniline into matrices of inorganic precipitate of stannicmolybdate. The composite material synthesized at pH 1.2 showed an ion exchange capacity 1.8 meq/g for Na+?ions. Ion exchange capacity, pH titration and distribution studies were carried out to determine the preliminary ion exchange properties of the material. The distribution studies showed the selectivity of Hg(II) ions by this material. The effect of temperature on the ion exchange capacity of the material at different temperatures had been studied. The sorption behavior of metal ions was also explored in different surfactant media.展开更多
N-alkylation of sulfosalicylic acid-doped polyaniline(PANI-SSA)was used to promote the anticorrosion performance of PANI-SSA/epoxy coating for 5083 Al alloy.PANI-SSA was modified with C5H11Br and C12H25Br in polar sol...N-alkylation of sulfosalicylic acid-doped polyaniline(PANI-SSA)was used to promote the anticorrosion performance of PANI-SSA/epoxy coating for 5083 Al alloy.PANI-SSA was modified with C5H11Br and C12H25Br in polar solvents IPA(isopropanol)and DMF(dimethylformamide),and then characterized by FTIR,XPS and sedimentation experiments.Results showed that alkanes were successfully linked onto the PANI-SSA chains.The compatibility between N-alkylated PANI-SSA and epoxy/xylene solution was improved.SEM results proved a better dispersion performance of N-alkylated PANI-SSA in epoxy coatings,with less holes and aggregations.Corrosion protection of the epoxy coatings incorporating PANI-SSA and N-alkylated PANI-SSA on 5083 Al alloy was studied by EIS and adhesion measurements in 3.5%NaCl solution.It turned out that the epoxy coating including C12H25Br-modified PANI-SSA in DMF has yielded the highest values of impedance modulus and best protective properties.展开更多
In this study,an integrative bioinspired coating system for antifouling and corrosion resistance was investigated,in which self-healing nanocapsules(tung oil calcium alginate,TO@CA),doped polyaniline and nano-titanium...In this study,an integrative bioinspired coating system for antifouling and corrosion resistance was investigated,in which self-healing nanocapsules(tung oil calcium alginate,TO@CA),doped polyaniline and nano-titanium dioxide nanocomposites(SPAn–TiO_(2))and a biostructure metal surface were combined.The antifouling property of the bioinspired coating resulted from the synergistic antifouling effect of nano-TiO_(2)and acid-doped polyaniline in SPAn–TiO_(2).The protonated nitrogen with a positive charge in SPAn–TiO_(2)and the intrinsic bactericidal property of nano-TiO_(2)could damage negatively charged single-celled chlorella,endowing the composite coating with good antifouling performance(less algae attached on the surfaces after a 90-day antifouling test and a conductivity test).The composite bioinspired coating had excellent corrosion resistance,which was due to the good synergistic anticorrosion barrier effect of SPAn–TiO_(2)with TO@CA nanocapsules and the repairing ability of microcracks of TO@CA nanocapsules during the corrosion process.The bioinspired coating with 2 wt%SPAn–TiO_(2)and 2 wt%TO@CA nanocapsules exhibited a better adhesion,corrosion resistance and antifouling performance than the other coatings did.展开更多
Vanadium oxides as cathode for zinc-ion batteries have attracted much attention because of their high theoretical capacity,flexible layered structure and abundant resources.However,cathodes are susceptible to the coll...Vanadium oxides as cathode for zinc-ion batteries have attracted much attention because of their high theoretical capacity,flexible layered structure and abundant resources.However,cathodes are susceptible to the collapse of their layered structure and the dissolution of vanadium after repeated long cycles,which worsen their capacities and cycling stabilities.Herein,a synergistic engineering of calcium-ion intercalation and polyaniline coating was developed to achieve the superior electrochemical performance of vanadium pentoxide for zinc-ion batteries.The pre-intercalation of calcium-ion between vanadium pentoxide layers as pillars increase the crystal structure’s stability,while the polyaniline coating on the cathodes improves the conductivity and inhibits the dissolution of vanadium.This synergistic engineering enables that the battery system based-on the polyaniline coated calcium vanadate cathode to deliver a high capacity of 406.4 mAh·g^(−1)at 1 A·g^(−1),an ultralong cycle life over 6000 cycles at 10 A·g^(−1)with 93%capacity retention and high-rate capability.The vanadium oxide cathode with synergistic engineering of calcium-ion intercalation and polyaniline coating was verified to effectively improve the electrochemical performance of zinc-ion batteries.展开更多
In this work, we developed a polyaniline （PANI）-coated selenium/carbon nanocomposite encapsulated in graphene sheets （PANI@Se/C-G）, with excellent performance in Li-Se batteries. The PANI@Se/C-G nanostructure pres...In this work, we developed a polyaniline （PANI）-coated selenium/carbon nanocomposite encapsulated in graphene sheets （PANI@Se/C-G）, with excellent performance in Li-Se batteries. The PANI@Se/C-G nanostructure presents attractive properties as cathode of Li-Se batteries, with a high specific capacity of 588.7 mAh·g^-1 at a 0.2C （1C = 675 mA·g^-1） rate after 200 cycles. Even at a high rate of 2C, a high capacity of 528.6 mAh·g^-1 is obtained after 500 cycles. The excellent cycle stability and rate performance of the PANI@Se/C-G composite can be attributed to the synergistic combination of carbon black （as the conductive matrix for Se） and the double conductive layer comprising the uniform PANI shell and the graphene sheets, which effectively improves the utilization of selenium and significantly enhances the electronic conductivity of the whole electrode.展开更多
文摘The modified zinc phosphate conversion coatings(ZPC) were formed on hot-dip galvanized(HDG) steel when 1.0 g/L sodium molybdate were added in a traditional zinc phosphate solution. The growth performance and corrosion resistance of the modified ZPC were investigated by SEM, open circuit potential(OCP), mass gain, potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) measurements and compared with those of the traditional ZPC. The results show that if sodium molybdate is added in a traditional zinc phosphate solution, the nucleation of zinc phosphate crystals is increased obviously; zinc phosphate crystals are changed from bulky acicular to fine flake and a more compact ZPC is obtained. Moreover, the mass gain and coverage of the modified ZPC are also boosted. The corrosion resistance of ZPC is increased with an increase in coverage, and thus the corrosion protection ability of the modified ZPC for HDG steel is more outstanding than that of the traditional ZPC.
基金Project(07BS405) supported by the Excellent Talents Foundation of Huaqiao Univeristy, China
文摘The phosphated hot-dip galvanized(HDG) sheets were post-sealed with sodium molybdate solution to improve the corrosion resistance of phosphate coatings. The morphology,chemical composition and corrosion resistance of the coatings were investigated using scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),Tafel polarization measurements and neutral salt spray(NSS) tests,and were compared with those of the single coatings. The results show that post-sealing the phosphated HDG steel with molybdate solution,the pores among the zinc phosphate crystals are sealed with molybdate films containing Zn,P,O and Mo,and the continuous composite coatings are formed. The suppression of both the anodic and the cathodic processes of zinc corrosion on the samples are enhanced significantly. The synergistic corrosion protection effect of the single phosphate coatings and molybdate films for zinc is evident. The corrosion resistance of the composite coatings increases with phosphating time up to 300 s.
文摘Polyaniline stannic molybdate—an organic-inorganic composite material, was prepared via sol-gel mixing of organic polymer polyaniline into matrices of inorganic precipitate of stannicmolybdate. The composite material synthesized at pH 1.2 showed an ion exchange capacity 1.8 meq/g for Na+?ions. Ion exchange capacity, pH titration and distribution studies were carried out to determine the preliminary ion exchange properties of the material. The distribution studies showed the selectivity of Hg(II) ions by this material. The effect of temperature on the ion exchange capacity of the material at different temperatures had been studied. The sorption behavior of metal ions was also explored in different surfactant media.
基金financially supported by the National Natural Science Foundation of China(Nos.51622106 and 51871049).
文摘N-alkylation of sulfosalicylic acid-doped polyaniline(PANI-SSA)was used to promote the anticorrosion performance of PANI-SSA/epoxy coating for 5083 Al alloy.PANI-SSA was modified with C5H11Br and C12H25Br in polar solvents IPA(isopropanol)and DMF(dimethylformamide),and then characterized by FTIR,XPS and sedimentation experiments.Results showed that alkanes were successfully linked onto the PANI-SSA chains.The compatibility between N-alkylated PANI-SSA and epoxy/xylene solution was improved.SEM results proved a better dispersion performance of N-alkylated PANI-SSA in epoxy coatings,with less holes and aggregations.Corrosion protection of the epoxy coatings incorporating PANI-SSA and N-alkylated PANI-SSA on 5083 Al alloy was studied by EIS and adhesion measurements in 3.5%NaCl solution.It turned out that the epoxy coating including C12H25Br-modified PANI-SSA in DMF has yielded the highest values of impedance modulus and best protective properties.
基金This work was financially supported by the National Defense Science and Technology Key Laboratory Fund Project(61420050403)the Young and Middle-aged Technology Innovation Leading Talents,and the Team Projects of Science and Technology Development Plan of Jilin Province(20230508041RC).
文摘In this study,an integrative bioinspired coating system for antifouling and corrosion resistance was investigated,in which self-healing nanocapsules(tung oil calcium alginate,TO@CA),doped polyaniline and nano-titanium dioxide nanocomposites(SPAn–TiO_(2))and a biostructure metal surface were combined.The antifouling property of the bioinspired coating resulted from the synergistic antifouling effect of nano-TiO_(2)and acid-doped polyaniline in SPAn–TiO_(2).The protonated nitrogen with a positive charge in SPAn–TiO_(2)and the intrinsic bactericidal property of nano-TiO_(2)could damage negatively charged single-celled chlorella,endowing the composite coating with good antifouling performance(less algae attached on the surfaces after a 90-day antifouling test and a conductivity test).The composite bioinspired coating had excellent corrosion resistance,which was due to the good synergistic anticorrosion barrier effect of SPAn–TiO_(2)with TO@CA nanocapsules and the repairing ability of microcracks of TO@CA nanocapsules during the corrosion process.The bioinspired coating with 2 wt%SPAn–TiO_(2)and 2 wt%TO@CA nanocapsules exhibited a better adhesion,corrosion resistance and antifouling performance than the other coatings did.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.22101309,52103277 and U1804126)the Key Scientific and Technological Project of Henan Province(Grant No.222102240001)the Startup Research of Henan Academy of Sciences(Grant No.231817001).
文摘Vanadium oxides as cathode for zinc-ion batteries have attracted much attention because of their high theoretical capacity,flexible layered structure and abundant resources.However,cathodes are susceptible to the collapse of their layered structure and the dissolution of vanadium after repeated long cycles,which worsen their capacities and cycling stabilities.Herein,a synergistic engineering of calcium-ion intercalation and polyaniline coating was developed to achieve the superior electrochemical performance of vanadium pentoxide for zinc-ion batteries.The pre-intercalation of calcium-ion between vanadium pentoxide layers as pillars increase the crystal structure’s stability,while the polyaniline coating on the cathodes improves the conductivity and inhibits the dissolution of vanadium.This synergistic engineering enables that the battery system based-on the polyaniline coated calcium vanadate cathode to deliver a high capacity of 406.4 mAh·g^(−1)at 1 A·g^(−1),an ultralong cycle life over 6000 cycles at 10 A·g^(−1)with 93%capacity retention and high-rate capability.The vanadium oxide cathode with synergistic engineering of calcium-ion intercalation and polyaniline coating was verified to effectively improve the electrochemical performance of zinc-ion batteries.
基金The authors would like to appreciate the financial support from the Natural Sciences Fund of Zhejiang Province （No. LQ17B010003） and the National Natural Science Foundation of China （NSFC） （No. 11604319）.
文摘In this work, we developed a polyaniline （PANI）-coated selenium/carbon nanocomposite encapsulated in graphene sheets （PANI@Se/C-G）, with excellent performance in Li-Se batteries. The PANI@Se/C-G nanostructure presents attractive properties as cathode of Li-Se batteries, with a high specific capacity of 588.7 mAh·g^-1 at a 0.2C （1C = 675 mA·g^-1） rate after 200 cycles. Even at a high rate of 2C, a high capacity of 528.6 mAh·g^-1 is obtained after 500 cycles. The excellent cycle stability and rate performance of the PANI@Se/C-G composite can be attributed to the synergistic combination of carbon black （as the conductive matrix for Se） and the double conductive layer comprising the uniform PANI shell and the graphene sheets, which effectively improves the utilization of selenium and significantly enhances the electronic conductivity of the whole electrode.
