The exploration of high-efficiency,long-durability,and cost-effectiveness transition metal doped carbon materials to replace the commercial Pt/C in oxygen reduction reaction(ORR)is greatly desirable for promoting the ...The exploration of high-efficiency,long-durability,and cost-effectiveness transition metal doped carbon materials to replace the commercial Pt/C in oxygen reduction reaction(ORR)is greatly desirable for promoting the advancement of sustainable energy devices.Herein,the Fe_(3)N and FeCo alloy decorated N-doped carbon hybrid material(denoted Fe_(3)N-FeCo@NC)is prepared and applied as the ORR catalyst,which is derived from the two-step pyrolysis of an intriguing complex consisted of metal-coordinated porous polydopamine(PDA)nanospheres(i.e.,Fe-PDA@Co)and melamine.The resulting Fe_(3)N-FeCo@NC delivers outstanding ORR activity with an onset potential(E_(on))of 1.05 V,a half-wave potential(E_(1/2))of 0.89 V,as well as excellent long-term stability and methanol resistance over Pt/C.Interestingly,the home-made Zn-air battery with Fe_(3)N-FeCo@NC as the air-cathode demonstrates much higher open-circuit voltage(1.50 vs.1.48 V),power density(141 vs.113 mW·cm^(−2))and specific capacity(806.6 vs.660.6 mAh·g^(−1)_(Zn))than those of Pt/C counterpart.Such a remarkable ORR activity of Fe_(3)N-FeCo@NC may stem from the synergistic effect of Fe_(3)N and FeCo active species,the large surface area,the hierarchical porous structure and the exceptional sphere/sheet hybridized architecture.展开更多
Developing efficient adsorbents for radon(Rn)capture from the ambient environment is of paramount importance for public health.However,it poses a great challenge due to the chemical inertness and extremely low molar c...Developing efficient adsorbents for radon(Rn)capture from the ambient environment is of paramount importance for public health.However,it poses a great challenge due to the chemical inertness and extremely low molar concentration of Rn in air.Herein,we report a zeolite imidazolate frameworkderived metallic carbon adsorbent(Zn@NPC)with record high Rn removal performance under ambient conditions.Upon one-step pyrolysis,the prepared Zn@NPC possesses pores with a preference for Rn and atomically dispersed Zn sites,achieving a high Rn removal efficiency that doubles in adsorption coefficient(9.47 L·g^(−1))and triples in adsorption kinetic coefficient(20.25 mL·g^(−1)·min^(−1))over the benchmark Rn adsorbent coconut activated charcoal.Density functional theory calculations elucidate the important role of the metal polarization effect,which cooperates with the pore size confinement effect to boost the overall Rn adsorption performance.This work launches a promising alternative for practical Rn capture.展开更多
Alkaline hydrogen evolution reaction(HER)offers a near-zero-emission approach to advance hydrogen energy.However,the activity limited by the multiple reaction steps involving H_(2)O molecules transfer,absorption,and a...Alkaline hydrogen evolution reaction(HER)offers a near-zero-emission approach to advance hydrogen energy.However,the activity limited by the multiple reaction steps involving H_(2)O molecules transfer,absorption,and activation still unqualified the thresholds of economic viability.Herein,we proposed a multisite complementary strategy that incorporates hydrophilic Mo and electrophilic V into Ni-based catalysts to divide the distinct steps on atomically dispersive sites and thus realize sequential regulation of the HER process.The Isotopic labeled in situ Raman spectroscopy describes 4-coordinated hydrogen bonded H_(2)O to be free H_(2)O passing the inner Helmholtz plane in the vicinity of the catalysts under the action of hydrophilic Mo sites.Furthermore,potential-dependent electrochemical impedance spectroscopy(EIS)reveals that electrophilic V sites with abundant 3d empty orbitals could activate the lone-pair electrons in the free H_(2)O molecules to produce more protic hydrogen,and dimerize into H_(2) at the Ni sites.By the sequential management of reactive H_(2)O molecules,NiMoV oxides multisite catalysts surpass Pt/C hydrogen evolution activity(49 mV@10 mA∙cm^(-2) over 140 h).Profoundly,this study provides a tangible model to deepen the comprehension of the catalyst–electrolyte interface and create efficient catalysts for diverse reactions.展开更多
This paper is focus on the corrosion resistance property analysis on three electric blasting of the coating-FeAl,FeCrAl,FeCrAlRE by electrochemical noise technology,acceleration of copper acetate salt spray accelerate...This paper is focus on the corrosion resistance property analysis on three electric blasting of the coating-FeAl,FeCrAl,FeCrAlRE by electrochemical noise technology,acceleration of copper acetate salt spray accelerated corrosion test.According to a comparative analysis of three tests coated by the Impedance curve,FeCrAlRE coating power spectral density(SPD)curve and Power curve,FeAl,FeCrAlRE coating has two more notable for the corrosion resistance properties than FeAl,FeCrAl coatings.展开更多
The fretting behavior of Zn-Al-Mg-RE coating prepared by high velocity arc spraying was studied for the first time in this paper.All specimens were fretted in air and 3.5%NaCl solution independently.The worn surfaces ...The fretting behavior of Zn-Al-Mg-RE coating prepared by high velocity arc spraying was studied for the first time in this paper.All specimens were fretted in air and 3.5%NaCl solution independently.The worn surfaces of the coating were investigated by scanning electron microscopy and X-ray energy dispersive spectroscopy.Fretting tests have shown that friction coefficient in 3.5%NaCl solution was similar to dry condition for Zn-Al-Mg-RE coating.Study of worn surfaces revealed the main mechanism in dry friction was the oxidative wear;while in 3.5%NaCl solution,the main mechanisms were delamination process and abrasive wear.展开更多
基金upported by the National Natural Science Foundation of China(No.52173207)the Natural Science Foundation of Hunan Province(Nos.2022JJ30563,2020JJ5542)the Outstanding Youth Fund Project of Hunan Provincial Department of Education(No.21B0119).
文摘The exploration of high-efficiency,long-durability,and cost-effectiveness transition metal doped carbon materials to replace the commercial Pt/C in oxygen reduction reaction(ORR)is greatly desirable for promoting the advancement of sustainable energy devices.Herein,the Fe_(3)N and FeCo alloy decorated N-doped carbon hybrid material(denoted Fe_(3)N-FeCo@NC)is prepared and applied as the ORR catalyst,which is derived from the two-step pyrolysis of an intriguing complex consisted of metal-coordinated porous polydopamine(PDA)nanospheres(i.e.,Fe-PDA@Co)and melamine.The resulting Fe_(3)N-FeCo@NC delivers outstanding ORR activity with an onset potential(E_(on))of 1.05 V,a half-wave potential(E_(1/2))of 0.89 V,as well as excellent long-term stability and methanol resistance over Pt/C.Interestingly,the home-made Zn-air battery with Fe_(3)N-FeCo@NC as the air-cathode demonstrates much higher open-circuit voltage(1.50 vs.1.48 V),power density(141 vs.113 mW·cm^(−2))and specific capacity(806.6 vs.660.6 mAh·g^(−1)_(Zn))than those of Pt/C counterpart.Such a remarkable ORR activity of Fe_(3)N-FeCo@NC may stem from the synergistic effect of Fe_(3)N and FeCo active species,the large surface area,the hierarchical porous structure and the exceptional sphere/sheet hybridized architecture.
基金funding support from the National Key R&D Program of China(grant nos.2021YFB3200400 and 2022YFE0105300)the New Cornerstone Science Foundation through the XPLORER PRIZE,the National Natural Science Foundation of China(grant nos.22276131,21825601,U21A20296,U1967217,12275190,U1932124,and 22206144)+2 种基金the Science Foundation of Jiangsu Province(grant no.BK20220026)the China-Portugal Joint Laboratory of Cultural Heritage Conservation Science(grant no.2021YFE0200100)Soochow University-Western University Centre for Synchrotron Radiation Research.
文摘Developing efficient adsorbents for radon(Rn)capture from the ambient environment is of paramount importance for public health.However,it poses a great challenge due to the chemical inertness and extremely low molar concentration of Rn in air.Herein,we report a zeolite imidazolate frameworkderived metallic carbon adsorbent(Zn@NPC)with record high Rn removal performance under ambient conditions.Upon one-step pyrolysis,the prepared Zn@NPC possesses pores with a preference for Rn and atomically dispersed Zn sites,achieving a high Rn removal efficiency that doubles in adsorption coefficient(9.47 L·g^(−1))and triples in adsorption kinetic coefficient(20.25 mL·g^(−1)·min^(−1))over the benchmark Rn adsorbent coconut activated charcoal.Density functional theory calculations elucidate the important role of the metal polarization effect,which cooperates with the pore size confinement effect to boost the overall Rn adsorption performance.This work launches a promising alternative for practical Rn capture.
文摘Alkaline hydrogen evolution reaction(HER)offers a near-zero-emission approach to advance hydrogen energy.However,the activity limited by the multiple reaction steps involving H_(2)O molecules transfer,absorption,and activation still unqualified the thresholds of economic viability.Herein,we proposed a multisite complementary strategy that incorporates hydrophilic Mo and electrophilic V into Ni-based catalysts to divide the distinct steps on atomically dispersive sites and thus realize sequential regulation of the HER process.The Isotopic labeled in situ Raman spectroscopy describes 4-coordinated hydrogen bonded H_(2)O to be free H_(2)O passing the inner Helmholtz plane in the vicinity of the catalysts under the action of hydrophilic Mo sites.Furthermore,potential-dependent electrochemical impedance spectroscopy(EIS)reveals that electrophilic V sites with abundant 3d empty orbitals could activate the lone-pair electrons in the free H_(2)O molecules to produce more protic hydrogen,and dimerize into H_(2) at the Ni sites.By the sequential management of reactive H_(2)O molecules,NiMoV oxides multisite catalysts surpass Pt/C hydrogen evolution activity(49 mV@10 mA∙cm^(-2) over 140 h).Profoundly,this study provides a tangible model to deepen the comprehension of the catalyst–electrolyte interface and create efficient catalysts for diverse reactions.
文摘This paper is focus on the corrosion resistance property analysis on three electric blasting of the coating-FeAl,FeCrAl,FeCrAlRE by electrochemical noise technology,acceleration of copper acetate salt spray accelerated corrosion test.According to a comparative analysis of three tests coated by the Impedance curve,FeCrAlRE coating power spectral density(SPD)curve and Power curve,FeAl,FeCrAlRE coating has two more notable for the corrosion resistance properties than FeAl,FeCrAl coatings.
文摘The fretting behavior of Zn-Al-Mg-RE coating prepared by high velocity arc spraying was studied for the first time in this paper.All specimens were fretted in air and 3.5%NaCl solution independently.The worn surfaces of the coating were investigated by scanning electron microscopy and X-ray energy dispersive spectroscopy.Fretting tests have shown that friction coefficient in 3.5%NaCl solution was similar to dry condition for Zn-Al-Mg-RE coating.Study of worn surfaces revealed the main mechanism in dry friction was the oxidative wear;while in 3.5%NaCl solution,the main mechanisms were delamination process and abrasive wear.
