The selection of appropriate materials for the transportation pipelines is of vital importance to ensure the safety operation in Carbon Capture,Utilisation and Storage(CCUS).To clarify the effects of Cr content in ste...The selection of appropriate materials for the transportation pipelines is of vital importance to ensure the safety operation in Carbon Capture,Utilisation and Storage(CCUS).To clarify the effects of Cr content in steel on the resistance against general and localised corrosion,electrochemistry methods combined with pH measurements and various surface analysis techniques were implemented on X65,1Cr,3Cr and 5Cr steel samples in a CO_(2)-saturated solution at 60°C and pH 6.6 during 192 h of immersion.Additionally,thermodynamic and kinetic analyses of the formation of the corrosion products on carbon steel and low-Cr steels were performed.The results show that the general corrosion resistance increased with rising Cr content without the presence of significant corrosion products formation.However,with the formation and development of the corrosion products,the general corrosion resistance reduced with the increase in Cr content.The formation of the compact crystalline FeCO3 on X65 and 1Cr steel surfaces offered superior general corrosion protection,while cannot provide enough localised corrosion protection.By contrast,the double-structural corrosion product layers on 3Cr and 5Cr steels notably suppressed the localised corrosion,but providing poor protection against general corrosion over long immersion periods.This study reveals the contributions of Cr content on general and localised corrosion resistance at various periods,providing references for material selection and evaluation in CO_(2) environments relevant for CCUS.展开更多
Introducing inorganic nanomaterials into a polymer matrix greatly improves the anticorrosion performance of epoxy coatings(EP);however,poor compatibility between the materials can limit the improvement in properties.I...Introducing inorganic nanomaterials into a polymer matrix greatly improves the anticorrosion performance of epoxy coatings(EP);however,poor compatibility between the materials can limit the improvement in properties.In this work,based on the high interface compatibility of two-dimensional(2D)Co_(2)(OH)_(2)BDC(BDC=1,4-benzenedicarboxylate)in the epoxy coating that we reported in previous work,we fabricated a 2D Co_(2)(OH)_(2)BDC-halloysite nanotube(HNT)nanocomposite have a structure consisting of alternating of nanosheets and nanotube by in situ synthesis.The nanocomposite was characterized by Fourier transform infrared spectroscopy,X-ray diffraction,and scanning electron microscopy.The mechanical and anticorrosion performance of the 2D Co_(2)(OH)_(2)BDC-HNT/EP coating was evaluated by mechanical tests and electrochemical impedance spectroscopy spectra.Compared with a conventional unreinforced epoxy coating,the 2D Co_(2)(OH)_(2)BDC-HNT/EP coating had higher mechanical strength and toughness,and the low-frequency impedance modulus of 2D Co_(2)(OH)_(2)BDC-HNT/EP coating was increased by three orders of magnitude,demonstrating the high corrosion resistance of our reinforced coating.展开更多
Combination of CO_(2) capture using inorganic alkali with subsequently electrochemical conversion of the resultant HCO_(3)^(-)to high-value chemicals is a promising route of low cost and high efficiency.The electroche...Combination of CO_(2) capture using inorganic alkali with subsequently electrochemical conversion of the resultant HCO_(3)^(-)to high-value chemicals is a promising route of low cost and high efficiency.The electrochemical reduction of HCO_(3)^(-)is challenging due to the inaccessible of negatively charged molecular groups to the electrode surface.Herein,we adopt a comprehensive strategy to tackle this challenge,i.e.,cascade of in situ chemical conversion of HCO_(3)^(-)to CO_(2) and CO_(2) electrochemical reduction in a flow cell.With a tailored Ni-N-S single atom catalyst(SACs),where sulfur(S)atoms located in the second shell of Ni center,the CO_(2)electroreduction(CO_(2)ER)to CO is boosted.The experimental results and density functional theory(DFT)calculations reveal that the introduction of S increases the p electron density of N atoms near Ni atom,thereby stabilizing^(*)H over N and boosting the first proton coupled electron transfer process of CO_(2)ER,i.e.,^(*)+e^(-)+^(*)H+^(*)CO_(2)→^(*)COOH.As a result,the obtained catalyst exhibits a high faradaic efficiency(FE_(CO)~98%)and a low overpotential of 425 mV for CO production as well as a superior turnover frequency(TOF)of 47397 h^(-1),outcompeting most of the reported Ni SACs.More importantly,an extremely high FECOof 90%is achieved at 50 mA cm^(-2)in the designed membrane electrode assembly(MEA)cascade electrolyzer fed with liquid bicarbonate.This work not only highlights the significant role of the second coordination on the first coordination shell of the central metal for CO_(2)ER,but also provides an alternative and feasible strategy to realize the electrochemical conversion of HCO_(3)^(-)to high-value chemicals.展开更多
基金supported by the National Key R&D Program of China(2021YFB4001601)the Natural Science Foundation of Shandong Province(ZR2021QE036)+3 种基金the Fundamental Research Funds for the Central Universities(22CX06052A)the Postgraduate Innovation Funding Project of China University of Petroleum(East China)(YCX2020070)the Fundamental Research Funds for the Central Universities(20CX02405A)the Development Fund of Shandong Key Laboratory of Oil&Gas Storage and Transportation Safety.
文摘The selection of appropriate materials for the transportation pipelines is of vital importance to ensure the safety operation in Carbon Capture,Utilisation and Storage(CCUS).To clarify the effects of Cr content in steel on the resistance against general and localised corrosion,electrochemistry methods combined with pH measurements and various surface analysis techniques were implemented on X65,1Cr,3Cr and 5Cr steel samples in a CO_(2)-saturated solution at 60°C and pH 6.6 during 192 h of immersion.Additionally,thermodynamic and kinetic analyses of the formation of the corrosion products on carbon steel and low-Cr steels were performed.The results show that the general corrosion resistance increased with rising Cr content without the presence of significant corrosion products formation.However,with the formation and development of the corrosion products,the general corrosion resistance reduced with the increase in Cr content.The formation of the compact crystalline FeCO3 on X65 and 1Cr steel surfaces offered superior general corrosion protection,while cannot provide enough localised corrosion protection.By contrast,the double-structural corrosion product layers on 3Cr and 5Cr steels notably suppressed the localised corrosion,but providing poor protection against general corrosion over long immersion periods.This study reveals the contributions of Cr content on general and localised corrosion resistance at various periods,providing references for material selection and evaluation in CO_(2) environments relevant for CCUS.
文摘Introducing inorganic nanomaterials into a polymer matrix greatly improves the anticorrosion performance of epoxy coatings(EP);however,poor compatibility between the materials can limit the improvement in properties.In this work,based on the high interface compatibility of two-dimensional(2D)Co_(2)(OH)_(2)BDC(BDC=1,4-benzenedicarboxylate)in the epoxy coating that we reported in previous work,we fabricated a 2D Co_(2)(OH)_(2)BDC-halloysite nanotube(HNT)nanocomposite have a structure consisting of alternating of nanosheets and nanotube by in situ synthesis.The nanocomposite was characterized by Fourier transform infrared spectroscopy,X-ray diffraction,and scanning electron microscopy.The mechanical and anticorrosion performance of the 2D Co_(2)(OH)_(2)BDC-HNT/EP coating was evaluated by mechanical tests and electrochemical impedance spectroscopy spectra.Compared with a conventional unreinforced epoxy coating,the 2D Co_(2)(OH)_(2)BDC-HNT/EP coating had higher mechanical strength and toughness,and the low-frequency impedance modulus of 2D Co_(2)(OH)_(2)BDC-HNT/EP coating was increased by three orders of magnitude,demonstrating the high corrosion resistance of our reinforced coating.
基金financially supported by the Natural Science Foundation of Shandong Province (ZR2020QB132,ZR2020MB025)the Opening Project of State Key Laboratory of High Performance Ceramics and Superfine Microstructure (SKL202108SIC)the Taishan Scholar Program of Shandong Province (ts201712046)。
文摘Combination of CO_(2) capture using inorganic alkali with subsequently electrochemical conversion of the resultant HCO_(3)^(-)to high-value chemicals is a promising route of low cost and high efficiency.The electrochemical reduction of HCO_(3)^(-)is challenging due to the inaccessible of negatively charged molecular groups to the electrode surface.Herein,we adopt a comprehensive strategy to tackle this challenge,i.e.,cascade of in situ chemical conversion of HCO_(3)^(-)to CO_(2) and CO_(2) electrochemical reduction in a flow cell.With a tailored Ni-N-S single atom catalyst(SACs),where sulfur(S)atoms located in the second shell of Ni center,the CO_(2)electroreduction(CO_(2)ER)to CO is boosted.The experimental results and density functional theory(DFT)calculations reveal that the introduction of S increases the p electron density of N atoms near Ni atom,thereby stabilizing^(*)H over N and boosting the first proton coupled electron transfer process of CO_(2)ER,i.e.,^(*)+e^(-)+^(*)H+^(*)CO_(2)→^(*)COOH.As a result,the obtained catalyst exhibits a high faradaic efficiency(FE_(CO)~98%)and a low overpotential of 425 mV for CO production as well as a superior turnover frequency(TOF)of 47397 h^(-1),outcompeting most of the reported Ni SACs.More importantly,an extremely high FECOof 90%is achieved at 50 mA cm^(-2)in the designed membrane electrode assembly(MEA)cascade electrolyzer fed with liquid bicarbonate.This work not only highlights the significant role of the second coordination on the first coordination shell of the central metal for CO_(2)ER,but also provides an alternative and feasible strategy to realize the electrochemical conversion of HCO_(3)^(-)to high-value chemicals.
