A novel titanium-supported nanoporous platinum(nanoPt/Ti)with a network structure was fabricated by using the hydrothermal process.Electrochemical oxidation of methanol on nanoPt/Ti was investigated in alkaline soluti...A novel titanium-supported nanoporous platinum(nanoPt/Ti)with a network structure was fabricated by using the hydrothermal process.Electrochemical oxidation of methanol on nanoPt/Ti was investigated in alkaline solutions for the first time.It was shown from the voltammograms that the peak current density of methanol oxidation on the nanoPt/Ti electrode increases significantly compared to the polycrystalline Pt.As shown in anodic polarization curves at 1 mV/s,the peak current density on the nanoPt/Ti is over 45 times higher than that on the polycrystalline Pt.Moreover,chronoamperometric measurements at different potentials locating round the peak potential of methanol oxidation exhibit highly stable current densities under the applied experimental conditions.展开更多
Electrochemical behavior of aqueous sodium sulfide solution at graphite anode,under the condition of different concentrations of Na2S and different temperatures,has been investigated by cyclic voltammetry and chronopo...Electrochemical behavior of aqueous sodium sulfide solution at graphite anode,under the condition of different concentrations of Na2S and different temperatures,has been investigated by cyclic voltammetry and chronopotentiometry.The results show that the anodic oxidation of aqueous sulfide solution is irreversible and that polysulfides are formed in rate-determining step of the anodic oxidation.With the increase of electrolytic temperature,potentials corresponding to anodic peaks shift to more negative and those corresponding to cathodic peaks shift to more positive,which indicates that the elevating of temperature is favorable to both oxidation of the sulfide and reduction of products polysulfides or elemental sulfur.Rate constants ks of standard electrode reaction for anodic oxidation of Na2S solution are between 10-4.08～10-4.35cm·s-1 at 70℃.Chronopotentiometric studies show two potential peaks in time-potential curve for a smaller current density value.The potential peaks may result from a self-catalytic effect taking place due to both dissolution of elemental sulfur by S2-,HS-and Sx2-,and transition reactions among polysulfides.The potential peaks disappear with the increasing of anodic current density.展开更多
A novel titanium-supported nanoporous network platinum electrode(nanoPt)with a enormous surface area was successfully fabricated with successive hydrothermal electrolytic processes.It was shown from cyclic voltammogra...A novel titanium-supported nanoporous network platinum electrode(nanoPt)with a enormous surface area was successfully fabricated with successive hydrothermal electrolytic processes.It was shown from cyclic voltammograms in alkaline solutions that current densities during the oxidation of formic acid on the nanoPt were much higher than those on a polycrystalline platinum(Pt),and that the oxidation peak current density on the nanoPt was almost 100 times higher than on Pt.It was observed from chrono potentiometric measurements that steady-state current densities on the nanoPt were also much higher than on Pt.Oscillatory behavior was observed both on Pt and on the nanoPt electrodes,but the linear galvanic voltammograms showed that oscillation arose in a much wider range of current densities on the nanoPt than on Pt.This novel nanoporous platinum electrode could be used repeatedly and its electrocatalytic activity was stable significantly.It would be a promising anodic material used in fuel cells.展开更多
A novel titanium-supported nickel electrode(Ni/Ti) was fabricated by a hydrothermal process using NiSO4 and hydrazine as raw materials. The structure of Ni/Ti was characterized by SEM and EDS. Oxidation of hydrazine o...A novel titanium-supported nickel electrode(Ni/Ti) was fabricated by a hydrothermal process using NiSO4 and hydrazine as raw materials. The structure of Ni/Ti was characterized by SEM and EDS. Oxidation of hydrazine on the Ni/Ti electrode in 1 mol·L-1 NaOH solution was studied with cyclic voltammograms(CV) and chronoamperometry (CA).The results show that Ni/Ti electrode was electrochemically active towards hydrazine oxidation. The high current density was recorded on the Ni/Ti electrode,and the onset potential for the hydrazine oxidation was-0.3 V as the hydrazine concentration was 70 mmol·L-1. This novel nickel electrode would be a promising anodic material used in direct hydrazine fuel cells.展开更多
A novel titanium-supported silver catalyst(Ag/Ti)with a 3D network structure was prepared by the hydrothermal process using polyethylene glycol as a reduction agent.Electrocatalytic activity of the Ag/Ti electrode tow...A novel titanium-supported silver catalyst(Ag/Ti)with a 3D network structure was prepared by the hydrothermal process using polyethylene glycol as a reduction agent.Electrocatalytic activity of the Ag/Ti electrode towards borohydride oxidation was evaluated by cyclic voltammograms(CVs).A direct oxidation process of borohydride on the Ag/Ti electrode was observed.The results showed that the Ag/Ti electrode presented a high anodic current density for borohydride oxidation,and the onset potential for borohydride oxidation was ca-0.64 V vs SCE at BH-4 concentration of 0.1 mol·L-1.This indicated that the Ag/Ti electrode exhibited high electrocatalytic activity for borohydride oxidation and it would be a promising anode used in direct borohydride fuel cells.展开更多
基金financial support from the National Natural Science Foundation of China(Grant No.21875062)the Innovation Training Program for College Students in Hunan Province(Grant No.S202210534022)。
文摘A novel titanium-supported nanoporous platinum(nanoPt/Ti)with a network structure was fabricated by using the hydrothermal process.Electrochemical oxidation of methanol on nanoPt/Ti was investigated in alkaline solutions for the first time.It was shown from the voltammograms that the peak current density of methanol oxidation on the nanoPt/Ti electrode increases significantly compared to the polycrystalline Pt.As shown in anodic polarization curves at 1 mV/s,the peak current density on the nanoPt/Ti is over 45 times higher than that on the polycrystalline Pt.Moreover,chronoamperometric measurements at different potentials locating round the peak potential of methanol oxidation exhibit highly stable current densities under the applied experimental conditions.
文摘Electrochemical behavior of aqueous sodium sulfide solution at graphite anode,under the condition of different concentrations of Na2S and different temperatures,has been investigated by cyclic voltammetry and chronopotentiometry.The results show that the anodic oxidation of aqueous sulfide solution is irreversible and that polysulfides are formed in rate-determining step of the anodic oxidation.With the increase of electrolytic temperature,potentials corresponding to anodic peaks shift to more negative and those corresponding to cathodic peaks shift to more positive,which indicates that the elevating of temperature is favorable to both oxidation of the sulfide and reduction of products polysulfides or elemental sulfur.Rate constants ks of standard electrode reaction for anodic oxidation of Na2S solution are between 10-4.08～10-4.35cm·s-1 at 70℃.Chronopotentiometric studies show two potential peaks in time-potential curve for a smaller current density value.The potential peaks may result from a self-catalytic effect taking place due to both dissolution of elemental sulfur by S2-,HS-and Sx2-,and transition reactions among polysulfides.The potential peaks disappear with the increasing of anodic current density.
文摘A novel titanium-supported nanoporous network platinum electrode(nanoPt)with a enormous surface area was successfully fabricated with successive hydrothermal electrolytic processes.It was shown from cyclic voltammograms in alkaline solutions that current densities during the oxidation of formic acid on the nanoPt were much higher than those on a polycrystalline platinum(Pt),and that the oxidation peak current density on the nanoPt was almost 100 times higher than on Pt.It was observed from chrono potentiometric measurements that steady-state current densities on the nanoPt were also much higher than on Pt.Oscillatory behavior was observed both on Pt and on the nanoPt electrodes,but the linear galvanic voltammograms showed that oscillation arose in a much wider range of current densities on the nanoPt than on Pt.This novel nanoporous platinum electrode could be used repeatedly and its electrocatalytic activity was stable significantly.It would be a promising anodic material used in fuel cells.
文摘A novel titanium-supported nickel electrode(Ni/Ti) was fabricated by a hydrothermal process using NiSO4 and hydrazine as raw materials. The structure of Ni/Ti was characterized by SEM and EDS. Oxidation of hydrazine on the Ni/Ti electrode in 1 mol·L-1 NaOH solution was studied with cyclic voltammograms(CV) and chronoamperometry (CA).The results show that Ni/Ti electrode was electrochemically active towards hydrazine oxidation. The high current density was recorded on the Ni/Ti electrode,and the onset potential for the hydrazine oxidation was-0.3 V as the hydrazine concentration was 70 mmol·L-1. This novel nickel electrode would be a promising anodic material used in direct hydrazine fuel cells.
文摘A novel titanium-supported silver catalyst(Ag/Ti)with a 3D network structure was prepared by the hydrothermal process using polyethylene glycol as a reduction agent.Electrocatalytic activity of the Ag/Ti electrode towards borohydride oxidation was evaluated by cyclic voltammograms(CVs).A direct oxidation process of borohydride on the Ag/Ti electrode was observed.The results showed that the Ag/Ti electrode presented a high anodic current density for borohydride oxidation,and the onset potential for borohydride oxidation was ca-0.64 V vs SCE at BH-4 concentration of 0.1 mol·L-1.This indicated that the Ag/Ti electrode exhibited high electrocatalytic activity for borohydride oxidation and it would be a promising anode used in direct borohydride fuel cells.
