Non Pt based metals and alloys as electrode materials for methyl alcohol fuel cells have been investigated w ith an aim of finding high electrocatalytic surface property for the faster electrode reactions.Electrodes w...Non Pt based metals and alloys as electrode materials for methyl alcohol fuel cells have been investigated w ith an aim of finding high electrocatalytic surface property for the faster electrode reactions.Electrodes w ere fabricated by electrodeposition on pure Al foil,from an electrolyte of Ni,Co,Fe salts.The optimum condition of electrodeposition w ere found out by a series of experiments,varying the chemistry of the electrolyte,pH valve,temperature,current and cell potential.Polarization study of the coated Ni-Co or Ni-CoFe alloy on pure Al w as found to exhibit high exchange current density,indicating an improved electro catalytic surface w ith faster charge-discharge reactions at anode and cathode and low overvoltage.Electrochemical impedance studies on coated and uncoated surface clearly show ed that the polarization resistance and impedance w ere decreased by Ni-Co or Ni-Co-Fe coating.X-ray diffraction(XRD),energy dispersive X-ray spectroscopy(EDX)and atomic absorption spectroscopy(AAS)studies confirmed the presence of alloying elements and constituents of the alloy.The morphology of the deposits from scanning electron microscope(SEM)images indicated that the electrode surface w as a three dimensional space w hich increased the effective surface area for the electrode reactions to take place.展开更多
One of the thrust areas of research is to find an alternative fuel to meet the increasing demand for energy.Glucose is a good source of alternative fuel for clean energy and is easily available in abundance from both ...One of the thrust areas of research is to find an alternative fuel to meet the increasing demand for energy.Glucose is a good source of alternative fuel for clean energy and is easily available in abundance from both naturally occurring plants and industrial processes.Electrochemical oxidation of glucose in fuel cell requires high electro-catalytic surface of the electrode to produce the clean electrical energy w ith minimum energy losses in the cell.Pt and Pt based alloys exhibit high electro-catalytic properties but they are expensive.For energy synthesis at economically cheap price,non Pt based inexpensive high electro catalytic material is required.Electro synthesized Zn O-Al2O3composite is found to exhibit high electro-catalytic properties for glucose oxidation.The Cyclic Voltammetry and Chronoamperometry curves reflect that the material is very much comparable to Pt as far as the maximum current and the steady state current delivered from the glucose oxidation are concerned.XRD image confirms the mixed oxide composite.SEM images morphology show increased 3D surface areas at higher magnification.This attributed high current delivered from electrochemical oxidation of glucose on this electrode surface.展开更多
Development of inexpensive non Pt based high electrocatalytic energy materials is the need of the hour for fuel cell electrode to produce clean alternative green energy from synthesized bio alcohol using biomass. MnO ...Development of inexpensive non Pt based high electrocatalytic energy materials is the need of the hour for fuel cell electrode to produce clean alternative green energy from synthesized bio alcohol using biomass. MnO 2,electro synthesized at different current density is found to be well performed electrocatalytic material,comparable to Pt,with higher current density,very lowovervoltage for the electrochemical oxidation of methanol. From EIS study,the polarization resistance of the coated MnO 2is found to be much lowand electrical double layer capacitance is high,the effect increases with increase in current density of electro deposition. XRD,EDX and AAS analysis confirm the M nO 2deposition. The morphology of SEM images exhibits an enhanced 3D effective substrate area,for electro oxidation of the fuel. A fewnano structured grains of the deposited M nO 2is also observed at higher current density. The fact supports that a high energetic inexpensive electro catalytic material has been found for fuel cell electrode to synthesis renewable energy from methanol fuel.展开更多
The unpredictable structure failures of carbon steel and low alloy steel leading to accidents may be caused by the propagation of a flaw or crack already present in the structure.Fracture toughness which describes the...The unpredictable structure failures of carbon steel and low alloy steel leading to accidents may be caused by the propagation of a flaw or crack already present in the structure.Fracture toughness which describes the ability of a material containing a crack to resist fracture is one of the most important material properties for design applications of metallic structures.Since this material property is influenced by several parameters,namely material chemistry,heat treatment,morphology of structure,it requires millions of experiments to be conducted to understand and predict it.So,mathematical modeling is one of the solutions to find the effect of these parameters and design future alloys.Stress–intensity factor(KIC)is a quantitative parameter of fracture toughness determining a maximum value of stress which may be applied to a specimen containing a crack(notch)of a certain length.An artificial neural network(ANN)model was developed using over 100 sets of data to study the effect of alloying elements on fracture toughness,KIC for the low alloy steel.20%of data was used for training,60%to develop predictive model and rest of the 20%for validation.The model can predict the fracture toughness of unknown new data close to 80%accuracy which is good enough for statistical modeling.The details of program code with ANN modeling steps have been explained.Prediction of fracture toughness by the model with variation of alloy composition as well as yield stress gives interesting and important information which may help in designing alloy which will resist crack propagation in a structure and hence enhance the life of structure to fail.展开更多
文摘Non Pt based metals and alloys as electrode materials for methyl alcohol fuel cells have been investigated w ith an aim of finding high electrocatalytic surface property for the faster electrode reactions.Electrodes w ere fabricated by electrodeposition on pure Al foil,from an electrolyte of Ni,Co,Fe salts.The optimum condition of electrodeposition w ere found out by a series of experiments,varying the chemistry of the electrolyte,pH valve,temperature,current and cell potential.Polarization study of the coated Ni-Co or Ni-CoFe alloy on pure Al w as found to exhibit high exchange current density,indicating an improved electro catalytic surface w ith faster charge-discharge reactions at anode and cathode and low overvoltage.Electrochemical impedance studies on coated and uncoated surface clearly show ed that the polarization resistance and impedance w ere decreased by Ni-Co or Ni-Co-Fe coating.X-ray diffraction(XRD),energy dispersive X-ray spectroscopy(EDX)and atomic absorption spectroscopy(AAS)studies confirmed the presence of alloying elements and constituents of the alloy.The morphology of the deposits from scanning electron microscope(SEM)images indicated that the electrode surface w as a three dimensional space w hich increased the effective surface area for the electrode reactions to take place.
基金"TEQIP,COE Phase Ⅱ "in Jadavpur University for the support of this work
文摘One of the thrust areas of research is to find an alternative fuel to meet the increasing demand for energy.Glucose is a good source of alternative fuel for clean energy and is easily available in abundance from both naturally occurring plants and industrial processes.Electrochemical oxidation of glucose in fuel cell requires high electro-catalytic surface of the electrode to produce the clean electrical energy w ith minimum energy losses in the cell.Pt and Pt based alloys exhibit high electro-catalytic properties but they are expensive.For energy synthesis at economically cheap price,non Pt based inexpensive high electro catalytic material is required.Electro synthesized Zn O-Al2O3composite is found to exhibit high electro-catalytic properties for glucose oxidation.The Cyclic Voltammetry and Chronoamperometry curves reflect that the material is very much comparable to Pt as far as the maximum current and the steady state current delivered from the glucose oxidation are concerned.XRD image confirms the mixed oxide composite.SEM images morphology show increased 3D surface areas at higher magnification.This attributed high current delivered from electrochemical oxidation of glucose on this electrode surface.
文摘Development of inexpensive non Pt based high electrocatalytic energy materials is the need of the hour for fuel cell electrode to produce clean alternative green energy from synthesized bio alcohol using biomass. MnO 2,electro synthesized at different current density is found to be well performed electrocatalytic material,comparable to Pt,with higher current density,very lowovervoltage for the electrochemical oxidation of methanol. From EIS study,the polarization resistance of the coated MnO 2is found to be much lowand electrical double layer capacitance is high,the effect increases with increase in current density of electro deposition. XRD,EDX and AAS analysis confirm the M nO 2deposition. The morphology of SEM images exhibits an enhanced 3D effective substrate area,for electro oxidation of the fuel. A fewnano structured grains of the deposited M nO 2is also observed at higher current density. The fact supports that a high energetic inexpensive electro catalytic material has been found for fuel cell electrode to synthesis renewable energy from methanol fuel.
文摘The unpredictable structure failures of carbon steel and low alloy steel leading to accidents may be caused by the propagation of a flaw or crack already present in the structure.Fracture toughness which describes the ability of a material containing a crack to resist fracture is one of the most important material properties for design applications of metallic structures.Since this material property is influenced by several parameters,namely material chemistry,heat treatment,morphology of structure,it requires millions of experiments to be conducted to understand and predict it.So,mathematical modeling is one of the solutions to find the effect of these parameters and design future alloys.Stress–intensity factor(KIC)is a quantitative parameter of fracture toughness determining a maximum value of stress which may be applied to a specimen containing a crack(notch)of a certain length.An artificial neural network(ANN)model was developed using over 100 sets of data to study the effect of alloying elements on fracture toughness,KIC for the low alloy steel.20%of data was used for training,60%to develop predictive model and rest of the 20%for validation.The model can predict the fracture toughness of unknown new data close to 80%accuracy which is good enough for statistical modeling.The details of program code with ANN modeling steps have been explained.Prediction of fracture toughness by the model with variation of alloy composition as well as yield stress gives interesting and important information which may help in designing alloy which will resist crack propagation in a structure and hence enhance the life of structure to fail.