In this study,the pure erosion behaviour of pure iron and its erosion-corrosion behaviour under different anodic polarization currents were investigated in various cathodic reactions(oxygen reduction,hydrogen ion redu...In this study,the pure erosion behaviour of pure iron and its erosion-corrosion behaviour under different anodic polarization currents were investigated in various cathodic reactions(oxygen reduction,hydrogen ion reduction,and water reduction)using a cylindrical stirring system.The corrosion-enhanced erosion(C-E)rates were determined for each condition.The results revealed that pure iron displayed similar pure erosion behaviour across all three cathodic reactions.When the cathodic reactions involve hydrogen ion reduction or water reduction,the erosion-corrosion of pure iron manifested as uniform damage,with the reduction in hardness being the main cause of the C-E in this case.Conversely,in the case of oxy-gen reduction reaction as the cathodic reaction,the erosion-corrosion presented as pitting damage,with the reduction in hardness resulting from localized concentration of anodic current and the formation of easily worn protruding flaky iron structures at the edges of the pits as the main mechanism of the C-E.Moreover,linear and exponential relationships were found between the C-E rate and the anodic current density for uniform damage and pitting damage,respectively.Finally,the concept of surface equivalent hardness was proposed,along with the establishment of a mathematical model for surface equivalent hardness based on the relationships between the C-E rate and the anodic current density.Utilizing the surface equivalent hardness enables the evaluation of the erosion rate on material surfaces considering the coupled effect.展开更多
This work presents a study on the use of cathodic protection as a measure against corrosion in pipelines.The cathodic protection,compliant with the API 5L standard,is implemented here by applying an impressed current,...This work presents a study on the use of cathodic protection as a measure against corrosion in pipelines.The cathodic protection,compliant with the API 5L standard,is implemented here by applying an impressed current,while carefully considering several essential variables,such as soil characteristics,the type and color of the pipeline material,as well as the placement and size of the anode.Therefore,it is crucial to optimize the location and values of anodic overflows or ground resistances to ensure a uniform distribution of potential across the entire structure.In this method,impressed current protection uses an auxiliary anode and an external direct current source to induce a current through the electrolyte and the pipeline,thus countering the resistance of the steel.This approach is advantageous as it allows for the adjustment of electrical characteristics,particularly current levels,to meet specific needs.The factors essential to the effectiveness of cathodic protection systems,which optimize the distribution of protection potential across the structure,largely depend on the precise management of ground resistances during anodic discharge,particularly the attenuation coefficient(α).These factors were studied,and the results obtained were presented and discussed based on their influence.展开更多
Coupling with high-voltage oxide cathode is the key to achieve high-energy density sulfide-based all-solid-state lithium batteries.However,the complex interfacial issues including the space charge layer effect and und...Coupling with high-voltage oxide cathode is the key to achieve high-energy density sulfide-based all-solid-state lithium batteries.However,the complex interfacial issues including the space charge layer effect and undesirable side reaction between sulfide solid-state electrolytes and oxide cathode materials are the main constraints on the development of high-performance allsolid-state lithium batteries,which lead to the continuous decay of electrochemical performance.Herein,different from the complicated coating procedure,a LiPO_(2)F_(2)additive engineering was proposed to achieve high-performance all-solid-state lithium batteries.With the introduction of LiPO_(2)F_(2)additive,a protective cathode-electrolyte interphase consisting of LiPxOyFz,LiF,and Li_(3)PO_(4)could be in situ formed to improve the interfacial stability between LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)and Li_(5.5)PS_(4.5)Cl_(1.5)(LPSC).Benefiting from this,the NCM811/LPSC/Li all-solid-state lithium battery exhibited impressive cyclic stability with a capacity retention of 85.5%after 600 cycles(at 0.5 C).Diverse and comprehensive characterization,combined with finite element simulation and density functional theory calculation fully demonstrated the effective component,interfacial stabilization function and enhanced kinetic of LiPO_(2)F_(2)-derived cathode-electrolyte interphase.This work provides not only a feasible and effective method to stabilize the cathodic interface but also worthy insight into interfacial design for high-performance all-solid-state lithium batteries.展开更多
Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical b...Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical behaviors,yet has not been unraveled.Here we propose an NH_(4)^(+)-modulated cationic solvation strategy to optimize cathodic spatial charge distribution and achieve dynamic Zn^(2+)/NH_(4)^(+)co-storage for boosting Zinc hybrid capacitors.Owing to the hierarchical cationic solvated structure in hybrid Zn(CF_(3)SO_(3))_(2)–NH_4CF_(3)SO_(3)electrolyte,high-reactive Zn^(2+)and small-hydrate-sized NH_4(H_(2)O))(4)^(+)induce cathodic interfacial Helmholtz plane reconfiguration,thus effectively enhancing the spatial charge density to activate 20%capacity enhancement.Furthermore,cathodic interfacial adsorbed hydrated NH_(4)^(+)ions afford high-kinetics and ultrastable C···H(NH_(4)^(+))charge storage process due to a much lower desolvation energy barrier compared with heavy and rigid Zn(H_(2)O)_6^(2+)(5.81 vs.14.90 eV).Consequently,physical uptake and multielectron redox of Zn^(2+)/NH_(4)^(+)in carbon cathode enable the zinc capacitor to deliver high capacity(240 mAh g^(-1)at 0.5 A g^(-1)),large-current tolerance(130 mAh g^(-1)at 50 A g^(-1))and ultralong lifespan(400,000cycles).This study gives new insights into the design of cathode–electrolyte interfaces toward advanced zinc-based energy storage.展开更多
Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because th...Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected.展开更多
Metal-organic framework[MOF,i.e.,NH_(2)-MIL-53(Al)]modified TiO_(2)(NMT)composite photoanodes were successfully prepared by hydrothermal synthesis and were used for the photoelectrochemical cathodic protection(PECCP)o...Metal-organic framework[MOF,i.e.,NH_(2)-MIL-53(Al)]modified TiO_(2)(NMT)composite photoanodes were successfully prepared by hydrothermal synthesis and were used for the photoelectrochemical cathodic protection(PECCP)of nickel-plated magnesium alloy(Mg/Ni).Results showed that the synthesis tem-perature significantly impacted the morphology and PECCP performance of the NMT photoanodes.The NMT@150 photoanode prepared at a reaction temperature of 150℃exhibited the best PECCP perfor-mance and produced a current density of 1980μA cm^(-2)under visible light irradiation,which was 19.8 times higher than that of a single TiO_(2)photoanode.The composite photoanode could polarize the open circuit potential of the coupled Mg/Ni electrode to-876 mV and remain relatively stable within 35 h.XPS and EPR tests showed that a Z-scheme heterojunction was formed between the NH_(2)-MIL-53(Al)and TiO_(2)nanotubes,allowing the photogenerated electrons to accumulate mainly on the conduction band of NH_(2)-MIL-53(Al).The heterojunction greatly promoted the separation and transfer of photogenerated electron-hole in the NMT composite photoanode,significantly enhancing the PECCP performance for Mg/Ni.展开更多
A new type of photoelectrochemical cathodic protection technology(a combination of seawater corrosion and biological fouling resistance)is being actively researched to alleviate the serious corrosion of marine metal m...A new type of photoelectrochemical cathodic protection technology(a combination of seawater corrosion and biological fouling resistance)is being actively researched to alleviate the serious corrosion of marine metal materials.At present,there is almost no research on anti-corrosion and anti-fouling dual functional materials.In this paper,Cu_(2)ZnSnS_(4)is attached to the surface of TiO,nanotubes through a one-step hydrothermal method for modification.The results indicate that when the hydrothermal reaction time is 24 h,Cu_(2)ZnSnS_(4)/TiO_(2)nanocomposite material exhibits excellent performance in coupling with the protected 304 SS,with its open circuit potential shifts negatively to-1.04 V.This material improves the separation efficiency of photogenerated electrons and effectively improves the photochemical cathodic protection of 304 stainless steel.The high removal rate of Staphylococcus aureus(up to 93%)of the as-prepared samples also proved that it has the effect of the anti-biological fouling.展开更多
The low photoelectric conversion efficiency of photoelectrode is an important factor that limits the application in photoelectrochemical cathodic protection(PECCP)field for marine anti-corrosion of metallic structures...The low photoelectric conversion efficiency of photoelectrode is an important factor that limits the application in photoelectrochemical cathodic protection(PECCP)field for marine anti-corrosion of metallic structures.In this work,a photoelectrode of TiO_(2)/CdZnS/ZnS triple-phase heterojunction was fabricated by loading the narrow-band CdZnS associated with the broad-band ZnS via hydrothermal and continuous ion layer adsorption methods,respectively.The composite of CdZnS enhances the photoelectric conversion ability of TiO_(2),while the ZnS composite can prevent the CdZnS from photo-corrosion and suppress the spillover of the photogenerated electrons.The three-phase heterostructure effectively improves the PECCP performance on 316 L stainless steel(SS)under simulated solar irradiation,especially in 3.5 wt%NaCl solution without the sacrificial agent.In addition,the prepared TiO_(2)/CdZnS/ZnS photoelectrode also performs anti-biofouling effect evidenced by the high removal efficiency of Pseudomonas aeruginosa(P.aeruginosa),which can be attributed to the oxidizability of photogenerated holes.The TiO_(2)/CdZnS/ZnS triple-phase heterojunction with desirable performance is a promising semiconductor material for the applications of PECCP and anti-biofouling.展开更多
Metallic pipeline corrosion poses a significant challenge in the petrochemical industry. In this study, the design and control of a stand-alone photovoltaic (PV)-powered cathodic protection (CP) system based on the im...Metallic pipeline corrosion poses a significant challenge in the petrochemical industry. In this study, the design and control of a stand-alone photovoltaic (PV)-powered cathodic protection (CP) system based on the impressed current method were investigated. The proposed CP system was applied to a 250 km long steel-buried pipeline in the Sharm El-Sheikh region of Egypt. The system design involved the numerical modeling of the anode bed for the impressed current CP (ICCP) system and the sizing of the DC power source, including the PV array and battery bank. The system was designed and controlled to deliver a constant and continuous anode current to protect the underground pipeline from corrosion during daylight and nighttime. A maximum power point tracking (MPPT) algorithm based on the fractional open-circuit voltage (FOCV) technique was implemented to maximize power extraction from the PV array. Additionally, a proportional-integral (PI) controller was optimized and employed to achieve MPPT, while another PI controller managed the anode current of the CP system. Safe charging and discharging of the system’s battery are ensured via an ON-OFF controller. The parameters of the PI controllers were optimized using the particle swarm optimization (PSO) technique. Simulation results demonstrated that the proposed CP system achieved the required protection objectives successfully.展开更多
For protonic ceramic fuel cells,it is key to develop material with high intrinsic activity for oxygen activation and bulk proton conductivity enabling water formation at entire electrode surface.However,a higher water...For protonic ceramic fuel cells,it is key to develop material with high intrinsic activity for oxygen activation and bulk proton conductivity enabling water formation at entire electrode surface.However,a higher water content which benefitting for the increasing proton conductivity will not only dilute the oxygen in the gas,but also suppress the O_(2)adsorption on the electrode surface.Herein,a new electrode design concept is proposed,that may overcome this dilemma.By introducing a second phase with high-hydrating capability into a conventional cobalt-free perovskite to form a unique nanocomposite electrode,high proton conductivity/concentration can be reached at low water content in atmosphere.In addition,the hydronation creates additional fast proton transport channel along the two-phase interface.As a result,high protonic conductivity is reached,leading to a new breakthrough in performance for proton ceramic fuel cells and electrolysis cells devices among available air electrodes.展开更多
The effect of 10% Si （mole fraction） addition on TiAlSiN coatings was studied. Ti0.5Al0.5N, Ti0.5Al0.4Si0.1N and Ti0.55Al0.35Si0.1N coatings were deposited on WC？Co substrates by cathodic arc evaporation. The mi...The effect of 10% Si （mole fraction） addition on TiAlSiN coatings was studied. Ti0.5Al0.5N, Ti0.5Al0.4Si0.1N and Ti0.55Al0.35Si0.1N coatings were deposited on WC？Co substrates by cathodic arc evaporation. The microstructure and mechanical properties were characterized by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, scanning electron microscopy （SEM）, nano-indentation measurement and scratch test. The mechanisms of how Si affects the properties and failure modes of TiAlSiN coatings were also discussed. The results show that the addition of 10% Si results in the formation of nc-（Ti,Al,Si）N/a-Si3N4 nano-composite structure. The hardness and toughness of TiAlSiN coatings increase, whereas the coating adhesion strength decreases. Compared with Ti0.55Al0.35Si0.1N coating, Ti0.5Al0.4Si0.1N coating has higher hardness but lower toughness. The dominant failure mode of TiAlN coating is wedging spallation due to low toughness and strong interfacial adhesion. The dominant failure mode of TiAlSiN coatings is buckling spallation due to improved toughness and weakened interfacial adhesion.展开更多
A novel type of composite electrode based on nmltiwalled carbon nanotubes coated with sheet-like cobalt hydroxide particles was used in supercapacitors. Cobalt hydroxide cathodlcally deposited fiom Co（NO3）O2 solutio...A novel type of composite electrode based on nmltiwalled carbon nanotubes coated with sheet-like cobalt hydroxide particles was used in supercapacitors. Cobalt hydroxide cathodlcally deposited fiom Co（NO3）O2 solution with carbon nanotubes as matrix exhibited large pseudo-capacitance of 322 F/g in 1 mol/L KOH. To characterize the cobalt hydroxide nanocomposite electrode, a charge-discharge cycling test, cyclic voltammetry, and an impedance test were done. This cobalt hydroxide composite exhibiting excellent pseudo-capacitive behavior （i.c. high reversibility, high specific capacitance, low impedance）, was demonstrated to be a candidate for the application of electrochemical supercapacitors. A combined capacitor consisting of cobalt hydroxide composite as a cathode and activated carbon fiber as an anode was reported. The electrochemical pcrformance of the combined capacitor was characterized by cyclic voltammetry and a dc charge/discharge test. The combined capacitor showed ideal capacitor behavior with an extended operating voltage of 1.4 V. According to the extended operating voltage, the energy density of the combined capacitor at a current density of 100 mA/cm^2 was found to be 11 Wh/kg. The combined capacitor exhibited high-energy density and stable power characteristics,展开更多
Cathodic deposition current density of the composite coatings increases when SiC par-ticles and rare earth (RE) were added in the bath, which is profitable for Ni- W-P alloy to deposit in the cathod, forming Ni-W-P-Si...Cathodic deposition current density of the composite coatings increases when SiC par-ticles and rare earth (RE) were added in the bath, which is profitable for Ni- W-P alloy to deposit in the cathod, forming Ni-W-P-SiC and RE-Ni-W-P-SiC composite coatings. On the contrary, the addition of PTFE in the bath decreases cathodic deposition current density of the coatings. The current density increases a little when the amount of RE is 7-9g/l; however, the current density increases greatly when the amount of RE is increased to 11-13g/l. Bui ij the amount of RE is raised further, the current density decreases. Hardness and wear resistance of RE-Ni-W-P-SiC composite coating have been studied, and the results show that the hardness and wear resistance of RE-Ni-W-P-SiC composite coating increase with increasing heat treatment tempera-ture, which reach peak values at 400℃; while the hardness and wear resistance of the coating decrease with the rise of heat treated temperature continuously.展开更多
Al-Zn-Mg alloys with different Zn/Mg mass ratios were evaluated as sacrificial anodes for cathodic protection of carbon steel in 3.5 wt.%Na Cl solution.The anodes were fabricated from pure Al,Zn and Mg metals using ca...Al-Zn-Mg alloys with different Zn/Mg mass ratios were evaluated as sacrificial anodes for cathodic protection of carbon steel in 3.5 wt.%Na Cl solution.The anodes were fabricated from pure Al,Zn and Mg metals using casting technique.Optical microscopy,SEM-EDS,XRD and electrochemical techniques were used.The results indicated that with decreasing Zn/Mg mass ratio,the grain size ofα(Al)and the particle size of the precipitates decreased while the volume fraction of the precipitates increased.The anode with Zn/Mg mass ratio>4.0 exhibited the lowest corrosion rate,while the anode with Zn/Mg mass ratio<0.62 gave the highest corrosion rate and provided the highest cathodic protection efficiency for carbon steel(AISI 1018).Furthermore,the results showed that the anode with Zn/Mg mass ratio<0.62 exhibited a porous corrosion product compared to the other anodes.展开更多
The cathodic reaction mechanisms in CO2 corrosion of low-Cr steels were investigated by potentiodynamic polarization and galvanostatic measurements.Distinct but different dominant cathodic reactions were observed at d...The cathodic reaction mechanisms in CO2 corrosion of low-Cr steels were investigated by potentiodynamic polarization and galvanostatic measurements.Distinct but different dominant cathodic reactions were observed at different p H levels.At the higher p H level(p H>~5),H2 CO3 reduction was the dominant cathodic reaction.The reaction was under activation control.At the lower pH level(pH<~3.5),H+reduction became the dominant one and the reaction was under diffusion control.In the intermediate area,there was a transition region leading from one cathodic reaction to another.The measured electrochemical impedance spectrum corresponded to the proposed cathodic reaction mechanisms.展开更多
Photoelectrochemical(PEC) cathodic protection is considered as an environment friendly method for metals anticorrosion. In this technology, a n-type semiconductor photoanode provides the photogenerated electrons for m...Photoelectrochemical(PEC) cathodic protection is considered as an environment friendly method for metals anticorrosion. In this technology, a n-type semiconductor photoanode provides the photogenerated electrons for metal to achieve cathodic protection. Comparing with traditional PEC photoanode for water splitting, it requires the photoanode providing a suitable cathodic potential for the metal, instead of pursuit ultimate photon to electric conversion efficiency, thus it is a more possible PEC technology for engineering application. To date, great efforts have been devoted to developing novel n-type semiconductors and advanced modification method to improve the performance on PEC cathodic protection metals. Herein, recent progresses in this field are summarized. We highlight the fabrication process of PEC cathodic protection thin film, various nanostructure controlling, doping, compositing methods and their operation mechanism. Finally, the current challenges and future potential works on improving the PEC cathodic protection performance are discussed.展开更多
In this work,the stress corrosion cracking(SCC)behavior of E690 steel base metal(BM)and different heat-affected zone(HAZ)microstructures,i.e.,coarse grain HAZ(CGHAZ),fine grain HAZ(FGHAZ),and intercritical HAZ(ICHAZ),...In this work,the stress corrosion cracking(SCC)behavior of E690 steel base metal(BM)and different heat-affected zone(HAZ)microstructures,i.e.,coarse grain HAZ(CGHAZ),fine grain HAZ(FGHAZ),and intercritical HAZ(ICHAZ),was investigated at different cathodic potentials in artificial seawater by slow strain rate tensile tests,scanning electron microscopy and electron back-scattered diffraction measurements.The results show that the HAZ microstructures and BM exhibit different SCC susceptibilities:FGHAZ<ICHAZ<BM<CGHAZ,which are controlled by anodic dissolution(AD)at the open circuit potential.With the cathodic potential equaling to-750 mV,the SCC susceptibility of the four microstructures increases because of the synergistic effect of AD and weak hydrogen embrittlement(HE).At-850 mV,AD is inhibited,and the SCC susceptibility of BM decreases,while the SCC susceptibility of the HAZ microstructures increases.At a potential below-850 mV,the SCC susceptibility of the four microstructures gradually increases because of the augment of HE,and the SCC susceptibility of the HAZ microstructures is higher than that of BM.The distinction reveals that the HAZ microstructures have the greater HE susceptibility than BM.展开更多
The crevice corrosion behavior of XTO steel was investigated with a wedge-shaped crevice assembly under -1000 m V （SCE） cathodic polarization in the solutions with various HCO3 concentrations. The potential, current...The crevice corrosion behavior of XTO steel was investigated with a wedge-shaped crevice assembly under -1000 m V （SCE） cathodic polarization in the solutions with various HCO3 concentrations. The potential, current, pH and the oxygen content within the crevice were measured with or without outside coupled specimen. The results indicated that the polarization potential of XTO steel in the crevice dropped with the increase of time under the cathodic polarization. There was a remarkable influence of HCO3 concentration on the potential of XTO steel in the crevice. When HCO3 concentration was up to 0.125%, the surface of the metal was covered with the corrosion products that resulted in the polarization extent of XTO steel decreased. The pH value in the crevice rose and it dropped gradually from the crevice mouth to the bottom under the cathodic polarization. With the increasing of HCO3 concentration, the hydrolyzation reaction of metal in the crevice bottom aggravated. Most of the dissolved oxygen in the crevice was consumed by the cathodic current. The maximum cathodic current on the metal surface was at the crevice mouth and it was much more than that at the crevice bottom.展开更多
A layer of graphene(GR)particles was successfully deposited at the interface between Co(OH)2 nanoparticles and TiO2 nanotubes,aiming to improve the photoelectrochemical performance of the large-bandgap semiconductor T...A layer of graphene(GR)particles was successfully deposited at the interface between Co(OH)2 nanoparticles and TiO2 nanotubes,aiming to improve the photoelectrochemical performance of the large-bandgap semiconductor TiO2.The obtained Co(OH)2/GR/TiO2 was extensively characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),UV–vis absorption spectra and photoluminescence(PL)emission spectra.Electrochemical impedance spectra,photogenerated potential-time(E-t),photocurrent density-time(i-t)and i-E curves and open circuit potential(OCP)curves were measured to investigate the photoelectrochemical activities and photogenerated cathodic protection properties.The results revealed that Co(OH)2/GR/TiO2 exhibits excellent photoelectrochemical and photogenerated cathodic performance due to synergistic effect between Co(OH)2 and graphene.Co(OH)2 and graphene co-modified TiO2 photoanode could provide an effective protection for 304 stainless steel(304 SS)in 3.5 wt%Na Cl solution for 12 h,which would be promising for future practical applications in the field of marine corrosion protection.展开更多
In this work,TiO_(2)nanotube arrays(NTAs)sensitized with MoS_(2)microspheres(MoS_(2)/TiO_(2)nanocomposites)were prepared on a flat Ti substrate via two-step anodization and hydrothermal method sequentially.TiO_(2)NTAs...In this work,TiO_(2)nanotube arrays(NTAs)sensitized with MoS_(2)microspheres(MoS_(2)/TiO_(2)nanocomposites)were prepared on a flat Ti substrate via two-step anodization and hydrothermal method sequentially.TiO_(2)NTAs were composed of many orderly nanotubes,whose large specific surface area was favorable for light absorption and MoS_(2)microsphere adhesion.The MoS_(2)microsphere as a narrow band gap semiconductor extended the TiO_(2)NTAs’absorption band edge to the visible region.The 2D structure of MoS_(2)microspheres and the construction of heterojunction electronic field at the interface of MoS_(2)microspheres and TiO_(2)NTAs promoted the separation of photoinduced carriers.The MoS_(2)/TiO_(2)nanocomposites could provide higher photoelectrochemical cathodic protection for 304 stainless steel(304 SS)under visible light than pristine TiO_(2)NTAs.展开更多
基金supported by the National Key Research and Development Program(No.2022YFC2806200)the National Key Research and Development Program(No.2023YFC2810800)the Natural Science Foundation of China(No.52001055).
文摘In this study,the pure erosion behaviour of pure iron and its erosion-corrosion behaviour under different anodic polarization currents were investigated in various cathodic reactions(oxygen reduction,hydrogen ion reduction,and water reduction)using a cylindrical stirring system.The corrosion-enhanced erosion(C-E)rates were determined for each condition.The results revealed that pure iron displayed similar pure erosion behaviour across all three cathodic reactions.When the cathodic reactions involve hydrogen ion reduction or water reduction,the erosion-corrosion of pure iron manifested as uniform damage,with the reduction in hardness being the main cause of the C-E in this case.Conversely,in the case of oxy-gen reduction reaction as the cathodic reaction,the erosion-corrosion presented as pitting damage,with the reduction in hardness resulting from localized concentration of anodic current and the formation of easily worn protruding flaky iron structures at the edges of the pits as the main mechanism of the C-E.Moreover,linear and exponential relationships were found between the C-E rate and the anodic current density for uniform damage and pitting damage,respectively.Finally,the concept of surface equivalent hardness was proposed,along with the establishment of a mathematical model for surface equivalent hardness based on the relationships between the C-E rate and the anodic current density.Utilizing the surface equivalent hardness enables the evaluation of the erosion rate on material surfaces considering the coupled effect.
文摘This work presents a study on the use of cathodic protection as a measure against corrosion in pipelines.The cathodic protection,compliant with the API 5L standard,is implemented here by applying an impressed current,while carefully considering several essential variables,such as soil characteristics,the type and color of the pipeline material,as well as the placement and size of the anode.Therefore,it is crucial to optimize the location and values of anodic overflows or ground resistances to ensure a uniform distribution of potential across the entire structure.In this method,impressed current protection uses an auxiliary anode and an external direct current source to induce a current through the electrolyte and the pipeline,thus countering the resistance of the steel.This approach is advantageous as it allows for the adjustment of electrical characteristics,particularly current levels,to meet specific needs.The factors essential to the effectiveness of cathodic protection systems,which optimize the distribution of protection potential across the structure,largely depend on the precise management of ground resistances during anodic discharge,particularly the attenuation coefficient(α).These factors were studied,and the results obtained were presented and discussed based on their influence.
基金support by the Department of Science&Technology of Zhejiang Province under grant no.2024C01095Zhejiang Provincial Natural Science Foundation of China under grant nos.LD22E020006 and LBMHD24E020001the National Natural Science Foundation of China(NSFC)under grant nos.21972127,U20A20253,and 22279116.
文摘Coupling with high-voltage oxide cathode is the key to achieve high-energy density sulfide-based all-solid-state lithium batteries.However,the complex interfacial issues including the space charge layer effect and undesirable side reaction between sulfide solid-state electrolytes and oxide cathode materials are the main constraints on the development of high-performance allsolid-state lithium batteries,which lead to the continuous decay of electrochemical performance.Herein,different from the complicated coating procedure,a LiPO_(2)F_(2)additive engineering was proposed to achieve high-performance all-solid-state lithium batteries.With the introduction of LiPO_(2)F_(2)additive,a protective cathode-electrolyte interphase consisting of LiPxOyFz,LiF,and Li_(3)PO_(4)could be in situ formed to improve the interfacial stability between LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)and Li_(5.5)PS_(4.5)Cl_(1.5)(LPSC).Benefiting from this,the NCM811/LPSC/Li all-solid-state lithium battery exhibited impressive cyclic stability with a capacity retention of 85.5%after 600 cycles(at 0.5 C).Diverse and comprehensive characterization,combined with finite element simulation and density functional theory calculation fully demonstrated the effective component,interfacial stabilization function and enhanced kinetic of LiPO_(2)F_(2)-derived cathode-electrolyte interphase.This work provides not only a feasible and effective method to stabilize the cathodic interface but also worthy insight into interfacial design for high-performance all-solid-state lithium batteries.
基金financially supported by the National Natural Science Foundation of China(Nos.22272118,22172111 and 22309134)the Science and Technology Commission of Shanghai Municipality,China(Nos.22ZR1464100,20ZR1460300 and 19DZ2271500)+3 种基金China Postdoctoral Science Foundation(2022M712402)Shanghai Rising-Star Program(23YF1449200)Zhejiang Provincial Science and Technology Project(2022C01182)the Fundamental Research Funds for the Central Universities(22120210529 and 2023-3-YB-07)。
文摘Compared with Zn^(2+),the current mainly reported charge carrier for zinc hybrid capacitors,small-hydrated-sized and light-weight NH_(4)^(+)is expected as a better one to mediate cathodic interfacial electrochemical behaviors,yet has not been unraveled.Here we propose an NH_(4)^(+)-modulated cationic solvation strategy to optimize cathodic spatial charge distribution and achieve dynamic Zn^(2+)/NH_(4)^(+)co-storage for boosting Zinc hybrid capacitors.Owing to the hierarchical cationic solvated structure in hybrid Zn(CF_(3)SO_(3))_(2)–NH_4CF_(3)SO_(3)electrolyte,high-reactive Zn^(2+)and small-hydrate-sized NH_4(H_(2)O))(4)^(+)induce cathodic interfacial Helmholtz plane reconfiguration,thus effectively enhancing the spatial charge density to activate 20%capacity enhancement.Furthermore,cathodic interfacial adsorbed hydrated NH_(4)^(+)ions afford high-kinetics and ultrastable C···H(NH_(4)^(+))charge storage process due to a much lower desolvation energy barrier compared with heavy and rigid Zn(H_(2)O)_6^(2+)(5.81 vs.14.90 eV).Consequently,physical uptake and multielectron redox of Zn^(2+)/NH_(4)^(+)in carbon cathode enable the zinc capacitor to deliver high capacity(240 mAh g^(-1)at 0.5 A g^(-1)),large-current tolerance(130 mAh g^(-1)at 50 A g^(-1))and ultralong lifespan(400,000cycles).This study gives new insights into the design of cathode–electrolyte interfaces toward advanced zinc-based energy storage.
文摘Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected.
基金supported by the National Natural Science Foundation of China(No.52271073)the Central Govern-ment Guided Special Program(No.2021ZYD0049)the Young Elite Scientists Sponsorship Program by CAST(No.2018QNRC001).
文摘Metal-organic framework[MOF,i.e.,NH_(2)-MIL-53(Al)]modified TiO_(2)(NMT)composite photoanodes were successfully prepared by hydrothermal synthesis and were used for the photoelectrochemical cathodic protection(PECCP)of nickel-plated magnesium alloy(Mg/Ni).Results showed that the synthesis tem-perature significantly impacted the morphology and PECCP performance of the NMT photoanodes.The NMT@150 photoanode prepared at a reaction temperature of 150℃exhibited the best PECCP perfor-mance and produced a current density of 1980μA cm^(-2)under visible light irradiation,which was 19.8 times higher than that of a single TiO_(2)photoanode.The composite photoanode could polarize the open circuit potential of the coupled Mg/Ni electrode to-876 mV and remain relatively stable within 35 h.XPS and EPR tests showed that a Z-scheme heterojunction was formed between the NH_(2)-MIL-53(Al)and TiO_(2)nanotubes,allowing the photogenerated electrons to accumulate mainly on the conduction band of NH_(2)-MIL-53(Al).The heterojunction greatly promoted the separation and transfer of photogenerated electron-hole in the NMT composite photoanode,significantly enhancing the PECCP performance for Mg/Ni.
基金Projects(42106051,U2106206)supported by the National Natural Science Foundation of China。
文摘A new type of photoelectrochemical cathodic protection technology(a combination of seawater corrosion and biological fouling resistance)is being actively researched to alleviate the serious corrosion of marine metal materials.At present,there is almost no research on anti-corrosion and anti-fouling dual functional materials.In this paper,Cu_(2)ZnSnS_(4)is attached to the surface of TiO,nanotubes through a one-step hydrothermal method for modification.The results indicate that when the hydrothermal reaction time is 24 h,Cu_(2)ZnSnS_(4)/TiO_(2)nanocomposite material exhibits excellent performance in coupling with the protected 304 SS,with its open circuit potential shifts negatively to-1.04 V.This material improves the separation efficiency of photogenerated electrons and effectively improves the photochemical cathodic protection of 304 stainless steel.The high removal rate of Staphylococcus aureus(up to 93%)of the as-prepared samples also proved that it has the effect of the anti-biological fouling.
基金financially supported by the Natural Science Foundation of Shandong(No.ZR2021MD002)the National Natural Science Foundation of China(Nos.42106051 and U2106206).
文摘The low photoelectric conversion efficiency of photoelectrode is an important factor that limits the application in photoelectrochemical cathodic protection(PECCP)field for marine anti-corrosion of metallic structures.In this work,a photoelectrode of TiO_(2)/CdZnS/ZnS triple-phase heterojunction was fabricated by loading the narrow-band CdZnS associated with the broad-band ZnS via hydrothermal and continuous ion layer adsorption methods,respectively.The composite of CdZnS enhances the photoelectric conversion ability of TiO_(2),while the ZnS composite can prevent the CdZnS from photo-corrosion and suppress the spillover of the photogenerated electrons.The three-phase heterostructure effectively improves the PECCP performance on 316 L stainless steel(SS)under simulated solar irradiation,especially in 3.5 wt%NaCl solution without the sacrificial agent.In addition,the prepared TiO_(2)/CdZnS/ZnS photoelectrode also performs anti-biofouling effect evidenced by the high removal efficiency of Pseudomonas aeruginosa(P.aeruginosa),which can be attributed to the oxidizability of photogenerated holes.The TiO_(2)/CdZnS/ZnS triple-phase heterojunction with desirable performance is a promising semiconductor material for the applications of PECCP and anti-biofouling.
文摘Metallic pipeline corrosion poses a significant challenge in the petrochemical industry. In this study, the design and control of a stand-alone photovoltaic (PV)-powered cathodic protection (CP) system based on the impressed current method were investigated. The proposed CP system was applied to a 250 km long steel-buried pipeline in the Sharm El-Sheikh region of Egypt. The system design involved the numerical modeling of the anode bed for the impressed current CP (ICCP) system and the sizing of the DC power source, including the PV array and battery bank. The system was designed and controlled to deliver a constant and continuous anode current to protect the underground pipeline from corrosion during daylight and nighttime. A maximum power point tracking (MPPT) algorithm based on the fractional open-circuit voltage (FOCV) technique was implemented to maximize power extraction from the PV array. Additionally, a proportional-integral (PI) controller was optimized and employed to achieve MPPT, while another PI controller managed the anode current of the CP system. Safe charging and discharging of the system’s battery are ensured via an ON-OFF controller. The parameters of the PI controllers were optimized using the particle swarm optimization (PSO) technique. Simulation results demonstrated that the proposed CP system achieved the required protection objectives successfully.
基金supported from the National Key R&D Program of China(No.2022YFB4002502)National Natural Science Foundation of China under(No.22278203,22279057)+4 种基金the Jiangsu Funding Program for Excellent Postdoctoral Talentthe Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)support from the Max Planck-POSTECH-Hsinchu Center for Complex Phase Materialssupport from the Fulbright Foundation Global Scholars Programthe U.S.Army Research Office under grant number W911NF-17-5401-0051
文摘For protonic ceramic fuel cells,it is key to develop material with high intrinsic activity for oxygen activation and bulk proton conductivity enabling water formation at entire electrode surface.However,a higher water content which benefitting for the increasing proton conductivity will not only dilute the oxygen in the gas,but also suppress the O_(2)adsorption on the electrode surface.Herein,a new electrode design concept is proposed,that may overcome this dilemma.By introducing a second phase with high-hydrating capability into a conventional cobalt-free perovskite to form a unique nanocomposite electrode,high proton conductivity/concentration can be reached at low water content in atmosphere.In addition,the hydronation creates additional fast proton transport channel along the two-phase interface.As a result,high protonic conductivity is reached,leading to a new breakthrough in performance for proton ceramic fuel cells and electrolysis cells devices among available air electrodes.
文摘The effect of 10% Si （mole fraction） addition on TiAlSiN coatings was studied. Ti0.5Al0.5N, Ti0.5Al0.4Si0.1N and Ti0.55Al0.35Si0.1N coatings were deposited on WC？Co substrates by cathodic arc evaporation. The microstructure and mechanical properties were characterized by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, scanning electron microscopy （SEM）, nano-indentation measurement and scratch test. The mechanisms of how Si affects the properties and failure modes of TiAlSiN coatings were also discussed. The results show that the addition of 10% Si results in the formation of nc-（Ti,Al,Si）N/a-Si3N4 nano-composite structure. The hardness and toughness of TiAlSiN coatings increase, whereas the coating adhesion strength decreases. Compared with Ti0.55Al0.35Si0.1N coating, Ti0.5Al0.4Si0.1N coating has higher hardness but lower toughness. The dominant failure mode of TiAlN coating is wedging spallation due to low toughness and strong interfacial adhesion. The dominant failure mode of TiAlSiN coatings is buckling spallation due to improved toughness and weakened interfacial adhesion.
文摘A novel type of composite electrode based on nmltiwalled carbon nanotubes coated with sheet-like cobalt hydroxide particles was used in supercapacitors. Cobalt hydroxide cathodlcally deposited fiom Co（NO3）O2 solution with carbon nanotubes as matrix exhibited large pseudo-capacitance of 322 F/g in 1 mol/L KOH. To characterize the cobalt hydroxide nanocomposite electrode, a charge-discharge cycling test, cyclic voltammetry, and an impedance test were done. This cobalt hydroxide composite exhibiting excellent pseudo-capacitive behavior （i.c. high reversibility, high specific capacitance, low impedance）, was demonstrated to be a candidate for the application of electrochemical supercapacitors. A combined capacitor consisting of cobalt hydroxide composite as a cathode and activated carbon fiber as an anode was reported. The electrochemical pcrformance of the combined capacitor was characterized by cyclic voltammetry and a dc charge/discharge test. The combined capacitor showed ideal capacitor behavior with an extended operating voltage of 1.4 V. According to the extended operating voltage, the energy density of the combined capacitor at a current density of 100 mA/cm^2 was found to be 11 Wh/kg. The combined capacitor exhibited high-energy density and stable power characteristics,
基金The project was supported by Yunnan Provincial Natural Science Foundation (95B11-5).
文摘Cathodic deposition current density of the composite coatings increases when SiC par-ticles and rare earth (RE) were added in the bath, which is profitable for Ni- W-P alloy to deposit in the cathod, forming Ni-W-P-SiC and RE-Ni-W-P-SiC composite coatings. On the contrary, the addition of PTFE in the bath decreases cathodic deposition current density of the coatings. The current density increases a little when the amount of RE is 7-9g/l; however, the current density increases greatly when the amount of RE is increased to 11-13g/l. Bui ij the amount of RE is raised further, the current density decreases. Hardness and wear resistance of RE-Ni-W-P-SiC composite coating have been studied, and the results show that the hardness and wear resistance of RE-Ni-W-P-SiC composite coating increase with increasing heat treatment tempera-ture, which reach peak values at 400℃; while the hardness and wear resistance of the coating decrease with the rise of heat treated temperature continuously.
文摘Al-Zn-Mg alloys with different Zn/Mg mass ratios were evaluated as sacrificial anodes for cathodic protection of carbon steel in 3.5 wt.%Na Cl solution.The anodes were fabricated from pure Al,Zn and Mg metals using casting technique.Optical microscopy,SEM-EDS,XRD and electrochemical techniques were used.The results indicated that with decreasing Zn/Mg mass ratio,the grain size ofα(Al)and the particle size of the precipitates decreased while the volume fraction of the precipitates increased.The anode with Zn/Mg mass ratio>4.0 exhibited the lowest corrosion rate,while the anode with Zn/Mg mass ratio<0.62 gave the highest corrosion rate and provided the highest cathodic protection efficiency for carbon steel(AISI 1018).Furthermore,the results showed that the anode with Zn/Mg mass ratio<0.62 exhibited a porous corrosion product compared to the other anodes.
基金financially supported by the National Natural Science Foundation of China (No. 51371034)Fundamental Research Funds for the Central Universities (No. 06500118)
文摘The cathodic reaction mechanisms in CO2 corrosion of low-Cr steels were investigated by potentiodynamic polarization and galvanostatic measurements.Distinct but different dominant cathodic reactions were observed at different p H levels.At the higher p H level(p H>~5),H2 CO3 reduction was the dominant cathodic reaction.The reaction was under activation control.At the lower pH level(pH<~3.5),H+reduction became the dominant one and the reaction was under diffusion control.In the intermediate area,there was a transition region leading from one cathodic reaction to another.The measured electrochemical impedance spectrum corresponded to the proposed cathodic reaction mechanisms.
基金supported by National Natural Science Foundation of China(Grant no.41506093)
文摘Photoelectrochemical(PEC) cathodic protection is considered as an environment friendly method for metals anticorrosion. In this technology, a n-type semiconductor photoanode provides the photogenerated electrons for metal to achieve cathodic protection. Comparing with traditional PEC photoanode for water splitting, it requires the photoanode providing a suitable cathodic potential for the metal, instead of pursuit ultimate photon to electric conversion efficiency, thus it is a more possible PEC technology for engineering application. To date, great efforts have been devoted to developing novel n-type semiconductors and advanced modification method to improve the performance on PEC cathodic protection metals. Herein, recent progresses in this field are summarized. We highlight the fabrication process of PEC cathodic protection thin film, various nanostructure controlling, doping, compositing methods and their operation mechanism. Finally, the current challenges and future potential works on improving the PEC cathodic protection performance are discussed.
基金financially supported by the National Environmental Corrosion Platform of China(NECP)the National Key Research and Development Program of China(Nos.2016YFB0300604 and 2017YFB0304701)the National Natural Science Foundation of China(Nos.51771028 and 51871024)。
文摘In this work,the stress corrosion cracking(SCC)behavior of E690 steel base metal(BM)and different heat-affected zone(HAZ)microstructures,i.e.,coarse grain HAZ(CGHAZ),fine grain HAZ(FGHAZ),and intercritical HAZ(ICHAZ),was investigated at different cathodic potentials in artificial seawater by slow strain rate tensile tests,scanning electron microscopy and electron back-scattered diffraction measurements.The results show that the HAZ microstructures and BM exhibit different SCC susceptibilities:FGHAZ<ICHAZ<BM<CGHAZ,which are controlled by anodic dissolution(AD)at the open circuit potential.With the cathodic potential equaling to-750 mV,the SCC susceptibility of the four microstructures increases because of the synergistic effect of AD and weak hydrogen embrittlement(HE).At-850 mV,AD is inhibited,and the SCC susceptibility of BM decreases,while the SCC susceptibility of the HAZ microstructures increases.At a potential below-850 mV,the SCC susceptibility of the four microstructures gradually increases because of the augment of HE,and the SCC susceptibility of the HAZ microstructures is higher than that of BM.The distinction reveals that the HAZ microstructures have the greater HE susceptibility than BM.
基金the National R&D Infrastructure and Facility Development Program of China(No.2005DKA10400)Financial support from the National Key Technology R&D Program of China (No.2006BAKO2B01-06)is also acknowledged.
文摘The crevice corrosion behavior of XTO steel was investigated with a wedge-shaped crevice assembly under -1000 m V （SCE） cathodic polarization in the solutions with various HCO3 concentrations. The potential, current, pH and the oxygen content within the crevice were measured with or without outside coupled specimen. The results indicated that the polarization potential of XTO steel in the crevice dropped with the increase of time under the cathodic polarization. There was a remarkable influence of HCO3 concentration on the potential of XTO steel in the crevice. When HCO3 concentration was up to 0.125%, the surface of the metal was covered with the corrosion products that resulted in the polarization extent of XTO steel decreased. The pH value in the crevice rose and it dropped gradually from the crevice mouth to the bottom under the cathodic polarization. With the increasing of HCO3 concentration, the hydrolyzation reaction of metal in the crevice bottom aggravated. Most of the dissolved oxygen in the crevice was consumed by the cathodic current. The maximum cathodic current on the metal surface was at the crevice mouth and it was much more than that at the crevice bottom.
基金supported financially by the National Natural Science Foundation of China(Nos.51622106 and 51871049)the Fundamental Research Funds for the Central Universities(No.160708001).
文摘A layer of graphene(GR)particles was successfully deposited at the interface between Co(OH)2 nanoparticles and TiO2 nanotubes,aiming to improve the photoelectrochemical performance of the large-bandgap semiconductor TiO2.The obtained Co(OH)2/GR/TiO2 was extensively characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),UV–vis absorption spectra and photoluminescence(PL)emission spectra.Electrochemical impedance spectra,photogenerated potential-time(E-t),photocurrent density-time(i-t)and i-E curves and open circuit potential(OCP)curves were measured to investigate the photoelectrochemical activities and photogenerated cathodic protection properties.The results revealed that Co(OH)2/GR/TiO2 exhibits excellent photoelectrochemical and photogenerated cathodic performance due to synergistic effect between Co(OH)2 and graphene.Co(OH)2 and graphene co-modified TiO2 photoanode could provide an effective protection for 304 stainless steel(304 SS)in 3.5 wt%Na Cl solution for 12 h,which would be promising for future practical applications in the field of marine corrosion protection.
基金financially supported by the National Natural Science Foundation of China(No.41827805)Chinese Academy of Engineering(No.2019-XZ-21)。
文摘In this work,TiO_(2)nanotube arrays(NTAs)sensitized with MoS_(2)microspheres(MoS_(2)/TiO_(2)nanocomposites)were prepared on a flat Ti substrate via two-step anodization and hydrothermal method sequentially.TiO_(2)NTAs were composed of many orderly nanotubes,whose large specific surface area was favorable for light absorption and MoS_(2)microsphere adhesion.The MoS_(2)microsphere as a narrow band gap semiconductor extended the TiO_(2)NTAs’absorption band edge to the visible region.The 2D structure of MoS_(2)microspheres and the construction of heterojunction electronic field at the interface of MoS_(2)microspheres and TiO_(2)NTAs promoted the separation of photoinduced carriers.The MoS_(2)/TiO_(2)nanocomposites could provide higher photoelectrochemical cathodic protection for 304 stainless steel(304 SS)under visible light than pristine TiO_(2)NTAs.
