Nano-diamond particles are co-deposited on Ti substrates with metal(Ti/Ni) nanoparticles(NPs) by the electrophoretic deposition(EPD) method combined with a furnace annealing at 800℃ under N_(2) atmosphere. Modificati...Nano-diamond particles are co-deposited on Ti substrates with metal(Ti/Ni) nanoparticles(NPs) by the electrophoretic deposition(EPD) method combined with a furnace annealing at 800℃ under N_(2) atmosphere. Modifications of structural and electron field emission(EFE) properties of the metal-doped films are investigated with different metal NPs concentrations. Our results show that the surface characteristics and EFE performances of the samples are first enhanced and then reduced with metal NPs concentration increasing. Both the Ti-doped and Ni-doped nano-diamond composite films exhibit optimal EFE and microstructural performances when the doping quantity is 5 mg. Remarkably enhanced EFE properties with a low turn-on field of 1.38 V/μm and a high current density of 1.32 mA/cm^(2) at an applied field of 2.94 V/μm are achieved for Ni-doped nano-diamond films, and are superior to those for Ti-doped ones. The enhancement of the EFE properties for the Ti-doped films results from the formation of the TiC-network after annealing. However, the doping of electron-rich Ni NPs and formation of high conductive graphitic phase are considered to be the factor, which results in marvelous EFE properties for these Ni-doped nano-diamond films.展开更多
The synergistic inhibitive effect of cysteine(Cys)and iodide ions on the corrosion behavior of copper was examined in a 0.5 mol·L^(-1) Na_(2)SO_(4) solution.Potentiodynamic polarization curve revealed that Cys ac...The synergistic inhibitive effect of cysteine(Cys)and iodide ions on the corrosion behavior of copper was examined in a 0.5 mol·L^(-1) Na_(2)SO_(4) solution.Potentiodynamic polarization curve revealed that Cys acted as a mixed type inhibitor with a major effect on the cathodic process,consequently decreased the corrosion current density by a great extent and shifted the corrosion potential negatively.The investigated results suggested that iodide ions can enhance the inhibition efficiency of Cys.The inhibition mechanism of Cys and the synergistic effect of the two examined reagents were investigated by fitting experimental impedance data according to a projected equivalent circuit for metal/electrolyte interface.Surface analysis further confirmed that the corrosion inhibition was realized due to the adsorption of the inhibitor molecules at the metal/solution interface.Langmuir adsorption isotherm was proposed to describe inhibition mechanism of Cys on copper surface.Active sites of Cys molecule were used to form inhibitor film on the copper surface.Addition of iodide ion increased its inhibition efficiency by enhancing adsorption of Cys cations through electrostatic interaction with I-pre-adsorbed on Cu surface.展开更多
基金supported by the Science and Technology Major Project of Shanxi Province,China (Grant No. 20181102013)the Fund from the “1331 Project”Engineering Research Center of Shanxi Province,China (Grant No. PT201801)。
文摘Nano-diamond particles are co-deposited on Ti substrates with metal(Ti/Ni) nanoparticles(NPs) by the electrophoretic deposition(EPD) method combined with a furnace annealing at 800℃ under N_(2) atmosphere. Modifications of structural and electron field emission(EFE) properties of the metal-doped films are investigated with different metal NPs concentrations. Our results show that the surface characteristics and EFE performances of the samples are first enhanced and then reduced with metal NPs concentration increasing. Both the Ti-doped and Ni-doped nano-diamond composite films exhibit optimal EFE and microstructural performances when the doping quantity is 5 mg. Remarkably enhanced EFE properties with a low turn-on field of 1.38 V/μm and a high current density of 1.32 mA/cm^(2) at an applied field of 2.94 V/μm are achieved for Ni-doped nano-diamond films, and are superior to those for Ti-doped ones. The enhancement of the EFE properties for the Ti-doped films results from the formation of the TiC-network after annealing. However, the doping of electron-rich Ni NPs and formation of high conductive graphitic phase are considered to be the factor, which results in marvelous EFE properties for these Ni-doped nano-diamond films.
基金financially supported by the Development and Reform Committee of PRC(People’s Republic of China)(No.YYXM-1412-0001)China Postdoctoral Science Foundation(No.2017M620612)+1 种基金the Fundamental Research Funds for the Central Universities(No.FRF-TP-16-040A1)the Program of the Ministry of Education of China for Introducing Talents of Discipline to Universities(111 Project)(No.B12012)。
文摘The synergistic inhibitive effect of cysteine(Cys)and iodide ions on the corrosion behavior of copper was examined in a 0.5 mol·L^(-1) Na_(2)SO_(4) solution.Potentiodynamic polarization curve revealed that Cys acted as a mixed type inhibitor with a major effect on the cathodic process,consequently decreased the corrosion current density by a great extent and shifted the corrosion potential negatively.The investigated results suggested that iodide ions can enhance the inhibition efficiency of Cys.The inhibition mechanism of Cys and the synergistic effect of the two examined reagents were investigated by fitting experimental impedance data according to a projected equivalent circuit for metal/electrolyte interface.Surface analysis further confirmed that the corrosion inhibition was realized due to the adsorption of the inhibitor molecules at the metal/solution interface.Langmuir adsorption isotherm was proposed to describe inhibition mechanism of Cys on copper surface.Active sites of Cys molecule were used to form inhibitor film on the copper surface.Addition of iodide ion increased its inhibition efficiency by enhancing adsorption of Cys cations through electrostatic interaction with I-pre-adsorbed on Cu surface.
