Page 1 of 8 - About 75 Essays
  • Operating Principles In PEM Fuel Cell

    Chapter-III OPERATING PRINIPLE AND LOSSES IN PEM FUEL CELL The polymer membrane is the heart of the PEM fuel cell which has some unique features. It allows protons but it is impermeable to gases, and hence it is known as a Proton Exchange Membrane. The membrane, which is squeezed between two electrodes (electrically conductive carbon cloths or carbon fiber papers) acts as electrolyte. A layer of catalyst particles (platinum) is placed at the interface between the porous electrode and polymer membrane. A schematic diagram of cell configuration and basic operating principles is shown in Fig. 1.1. Hydrogen, which is fed into one side of the membrane, splits into its primary elements, i.e., one proton and one electron at anode. Protons will pass through the membrane, while the electrons travel through the electrically conductive electrodes, through current collectors, and through the open circuit where they perform useful work and return to the other side of the membrane. At the catalyst sites between the membrane and the other electrode they meet with the protons which had passed through the membrane. Oxygen is fed from the other side of the membrane. Water is produced by an electrochemical reaction when the proton and electron combine with oxygen at the cathode. The formed water is pushedout of the cell with the excess flow of oxygen. The continuous flow of the electrons through an external circuit results in production of direct electrical current. Thus, the hydrogen side…

    Words: 1940 - Pages: 8
  • Effects Of Metal Electrodeposition

    Metal electrodeposition is the process of reduction reaction and crystallization of metal ions in an electrolytic cell according to the mechanism of electrolysis. Electrodeposition is one of the main methods for improving and enhancing the metal substrate property. Now, in order to overcome the defect of single electrodeposition with shortcomings of cracks, pores, pits, pocking and so on, the modern new techniques sprang up such as jet electrodeposition [1], ultrasonic vibration assisted…

    Words: 1846 - Pages: 8
  • Consequences Of Conductance In Electrolysis

     Second Law: The mass of substance produced in electrolysis directly proportional to its equivalent mass. W1 / E1 = W2 / E2 = W3 / E3...  Third Law: The mass of a substance produced in electrolysis is directly proportional to the number of electrons per mole needed to cause desired change in oxidation state. Conductivity When voltage is applied to the electrodes immersed into an electrolyte solution, ions of electrolyte move, and thus, electric current flows through the electrolytic…

    Words: 1128 - Pages: 5
  • Fuel Cells And Its Effect On The Environment

    Within the last decade, Fuel Cells have become more advanced and available to buy. The Fuel Cell was originally thought up in 1839, by a man named Sir William Grove, but a working model wasn 't made until 1959. After being used in one of NASA’s space programmes, the research and development on Fuel Cells died down and was put back in storage. In the 1900’s scientists decided to look at new ways to make these products available for commercialization. This has been successful as they are now used…

    Words: 1397 - Pages: 6
  • Compare The Construction And Operation Of A Ni-Cad Battery With A Lead-Acid Battery

    Q1. Describe the construction and operation of a Ni-Cad battery. Compare and contrast the Ni-Cad battery with a Lead-Acid battery. a. Construction: figure 1. Ni-cad battery construction Ni-Cad battery refers to Nickel-cadmium battery which is widely used in industrial world. Basically, the Ni-Cad battery consists of positive and negative plates, separators, electrolyte, cell vent, and cell container. The positive plate in Ni-Cad battery is Nickel Hydroxide Ni(OH)2. However, the negative…

    Words: 1065 - Pages: 5
  • Catalyst Layer Essay

    A catalyst layer is usually the slimmest layer in a PEM fuel cell; however this is an extremely complex component because of its porosity, several phases, and reactions (Spiegel 2008). An efficient catalyst layer should provide several functions at the same time; transporting the electron and the proton, supplying oxygen and hydrogen and water management. The structure and composition of the catalyst layer affects all these roles. Optimization of the catalyst layer can provide for all these…

    Words: 987 - Pages: 4
  • Electrochemical Performance Case Study

    Electrochemical Performance. To evaluate the electrochemical behaviors of the highly open framework of the as synthesized LTH on nickel foam electrodes NCA-L-@NF, NCA-L@G-NF and NCA-L@ BG-NF with three different feeding mole ratios , which is the best morphological foundation for fast redox reaction and charge accumulation, its potential application in high-performance supercapacitor has been investigated by cyclic voltammetry (CV), galvanostatic charge-discharge and electrochemical impedance…

    Words: 812 - Pages: 4
  • Salt Water Lab Report

    Conductivity of Salt Water/ Salt Water Circuit Introduction to Physics UBT 1- Task #2 19/11/2015 Western Governors University Thiago Predebon Introduction: Saltwater Circuit; Did you know that you can use salt water to make a light bulb shine? It sounds crazy, but it's true! This is because salt water is a good conductor of electricity. Salt molecules are made of sodium ions and chlorine ions. (An ion is an atom that has an electrical charge because it has either gained or lost an…

    Words: 1131 - Pages: 5
  • Synthesis Of Pb Film

    In this study, multiwalled carbon nanotubes@poly(p-phenylenediamine)-prussian blue (MWCNTs@PpPD-PB) nanocomposites were synthesized and used for the nonenzymatic electrochemical detection of hydrogen peroxide (H2O2). The PpPD layer also helps the MWCNTs to be dispersed in the water together with the PB formation and fixing on the surface of the MWCNTs. Moreover, PpPD, a conductive polymer, increases the electronic conductivity and stability of MWCNTs. By combining the selectivity and catalytic…

    Words: 768 - Pages: 4
  • Capacitance Properties Of Polyaniline Essay

    Capacitance properties of electrodeposited polyaniline films on stainless steel substrate. A.A. Al-Owais1,I. S. El-Hallag2, M.A. Ghanem3 1,3Chemistry Department, Faculty of Science, King Saud University, Riyadh ,SA 2Chemistry Department, Faculty of Science, Tanta University, Tanta, 31527, Egypt Abstract. Polyaniline (PANI) thin films were successfully synthesized from a mixed solution of 1M aniline and two different concentration solutions of H2SO4 on a stainless steel substrate. The…

    Words: 1807 - Pages: 8
  • Previous
    Page 1 2 3 4 5 6 7 8

Related Topics:

Popular Topics: