Energy Dispersive Spectroscopy EDS and its Application

Electrons inelastically scattered within the excitation volume of a specimen deposit some energy in many atoms. In order to return to ground state, the atom releases a distinct quantum of energy. If the excited atom ejects an iimer-shell electron, an outer-shell electron fills that vacancy and emits an X-ray having energy equal to the difference between the two electron shells. The detection of the X-rays emitted 

The X-rays emitted carry a characteristic energy and wavelength, which when measured will reveal the elemental composition of the specimen. Even if it may not be possible to excite or detect all the characteristic X-rays of a given element, in general an element may be uniquely identified by the detectable lines. Energy dispersive spectrometers are capable of analyzing X-rays in the range of 0.7-20 keV emitted from elements with atomic numbers 10. In addition to qualitative element analyses, quantitative analyses are possible because the intensity of the emitted radiation is proportional to the concentration of that element. But a precise quantitative analysis of elemental content cannot be expected, especially when a standard sample does not exist. 

Many efforts have been made to find the proper alternative to Nafion at elevated temperature operation for PEMFCs, as Nafion degrades at temperatures higher than 110-130 °C. It was found that the organie-inorganic composite membrane can improve its own mechanical strength and thermal stability at 

6 Analysis of the Stability of Catalysts by the Thermal Analysis Method 

Thermal analysis refers to a group of techniques in which some physical property of the sample is monitored as a function of temperature while the temperature of 

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