scholarly journals Analysis of Compositional Gradients in Cu(In,Ga)(S,Se)2 Solar Cell Absorbers Using Energy Dispersive X-ray Analysis with Different Acceleration Energies

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2861
Author(s):  
Ulrike Künecke ◽  
Matthias Schuster ◽  
Peter Wellmann
Keyword(s):  
Solar Cell ◽  
Optical Emission ◽  
Process Variations ◽  
Front Surface ◽  
Energy Dispersive ◽  
Emission Spectrometry ◽  
Large Area ◽  
X Ray ◽  
Compositional Gradients

The efficiency of Cu(In,Ga)(S,Se)2 (CIGSSe) solar cell absorbers can be increased by the optimization of the Ga/In and S/Se gradients throughout the absorber. Analyzing such gradients is therefore an important method in tracking the effectiveness of process variations. To measure compositional gradients in CIGSSe, energy dispersive X-ray analysis (EDX) with different acceleration energies performed at both the front surface and the backside of delaminated absorbers was used. This procedure allows for the determination of compositional gradients at locations that are millimeters apart and distributed over the entire sample. The method is therefore representative for a large area and yields information about the lateral homogeneity in the millimeter range. The procedure is helpful if methods such as secondary ion-mass (SIMS), time-of-flight SIMS, or glow-discharge optical emission spectrometry (GDOES) are not available. Results of such EDX measurements are compared with GDOES, and they show good agreement. The procedure can also be used in a targeted manner to detect local changes of the gradients in inhomogeneities or points of interest in the µm range. As an example, a comparison between the compositional gradients in the regular absorber and above the laser cut separating the Mo back contact is shown.

Determination of small concentrations of hafnia in zirconia by selective excitation energy dispersive X-ray emission spectrometry

1994 ◽  
Vol 349 (6) ◽  
pp. 434-437 ◽  
Author(s):  
R. M. Agrawal ◽  
S. N. Jha ◽  
Rugmini Kaimal ◽  
S. K. Malhotra ◽  
B. L. Jangida
Keyword(s):  
Excitation Energy ◽  
Selective Excitation ◽  
Energy Dispersive ◽  
Emission Spectrometry ◽  
X Ray

Application of Energy Dispersive X-ray Fluorescence Spectrometry to the Determination of Copper, Manganese, Zinc, and Sulfur in Grass (Lolium perenne) in Grazed Agricultural Systems

2018 ◽  
Vol 72 (11) ◽  
pp. 1661-1673 ◽  
Author(s):  
Karen Daly ◽  
Anna Fenelon
Keyword(s):  
Excellent Agreement ◽  
Energy Dispersive ◽  
Emission Spectrometry ◽  
Icp Oes ◽  
X Ray ◽  
Fundamental Parameters ◽  
True Value ◽  
Calibration Methods ◽  
Conventional Methods

Conventional methods for the determination of major nutrients and trace elements in grass rely on acid digestion followed by analysis using inductively coupled plasma optical emission spectrometry (ICP-OES), which can be both time consuming and costly. Energy dispersive X-ray fluorescence (EDXRF) spectrometry offers a rapid alternative that can determine multiple elements in a single scan. Copper, Mn, Zn, and S in grass samples were determined using EDXRF with a number of different calibration approaches using both empirical standards and the theoretical relationships between concentrations and intensities. Using an existing archive of 467 grass samples of known concentrations, a suite of 30 samples was selected as empirical grass standards to build a calibration set between sample concentrations and EDXRF intensities. The theoretical or standardless approach used the fundamental parameters method to determine element concentrations. To validate the two calibration methods, 59 samples were randomly selected from the same archive and database and analyzed by EDXRF. The measurements of Cu, Mn, Zn, and S were compared with the ICP-OES values using agreement statistics. An excellent correlation was observed between the concentrations determined by EDXRF and ICP-OES ( R > 0.90) regardless of the calibration approach. However, agreement and closeness to the true value varied and were assessed using agreement statistics. Across all elements, the empirically calibrated samples were in excellent agreement with the values determined by ICP-OES. The theoretical calibrations provided excellent agreement for Mn and Zn, but a degree of fixed and proportional bias was observed in the Cu and S values. Fixed bias was corrected by subtracting the computed bias from the EDXRF concentrations and improved the overall agreement. Similarly, proportional bias was corrected using the linear regression model to predict the corrected EDXRF values. This improved the overall agreement with the ICP-OES values for both Cu and S using corrected fundamental parameters calibrations. This study provides a practical basis for the use of EDXRF to determine Cu, Mn, Zn, and S in grass samples to monitor forage quality in grazed systems without the need for sample digestion. The observed fixed and proportional bias in the theoretical calibrations can be corrected provided that a good correlation exists between EDXRF and conventional methods.

Determination of Zn in Dry Feeds for Cats and Dogs by Energy-Dispersive X-Ray Fluorescence Spectrometry

2016 ◽  
Vol 99 (6) ◽  
pp. 1572-1575 ◽  
Author(s):  
Dayara Virgínia L Ávila ◽  
Sidnei O Souza ◽  
Silvânio Silvério L Costa ◽  
Rennan Geovanny O Araujo ◽  
Carlos Alexandre B Garcia ◽  
...  
Keyword(s):  
Confidence Level ◽  
Analytical Method ◽  
Inductively Coupled Plasma ◽  
Comparative Method ◽  
Direct Analysis ◽  
Energy Dispersive ◽  
Emission Spectrometry ◽  
Icp Oes ◽  
X Ray

Abstract This work describes an analytical method for Zn determination in dry feeds for cats and dogs by energy-dispersive X-ray fluorescence (EDXRF). Samples of dry feed were powdered and prepared in the form of pellets for direct analysis by EDXRF. The LOQ (10σ) was 0.4 mg/kg. The samples were also analyzed by inductively coupled plasma-optical emission spectrometry (ICP-OES) as an independent comparative method. Application of a paired t-test showed no significant differences between Zn concentrations obtained by EDXRF and ICP-OES (at a 95% confidence level). Analysis of variance was also applied to the results and revealed no significant differences between the two techniques (at a 95% confidence level). The precision, expressed as the RSD (n = 3), was RSD < 4.55%. This analytical method provides a simple, rapid, accurate, and precise determination of Zn in dry feeds for cats and dogs by EDXRF as direct, solid-sample analysis.

scholarly journals A rapid and multi-element method for the analysis of major nutrients in grass (Lolium perenne) using energy-dispersive X-ray fluorescence spectroscopy

2017 ◽  
Vol 56 (1) ◽  
pp. 1-11 ◽  
Author(s):  
K. Daly ◽  
A. Fenelon
Keyword(s):  
Lolium Perenne ◽  
Excellent Agreement ◽  
Inductively Coupled Plasma ◽  
Animal Health ◽  
Correlation Coefficients ◽  
Optical Emission ◽  
Energy Dispersive ◽  
Emission Spectrometry ◽  
Icp Oes ◽  
X Ray

AbstractElemental analysis of grass (Lolium perenne) is essential in agriculture to ensure grass quality and animal health. Energy-dispersive X-ray fluorescence (EDXRF) spectroscopy is a rapid, multi-element alternative to current methods using acid digestion and inductively coupled plasma optical emission spectrometry (ICP-OES). Percentage phosphorus (P), potassium (K), magnesium (Mg) and calcium (Ca), determined from grass samples using EDXRF, were within 0.035, 0.319, 0.025 and 0.061, respectively, of ICP-OES values. Concordance correlation coefficients computed using agreement statistics ranged from 0.4379 to 0.9669 (values close to one indicate excellent agreement); however, the level of agreement for each element depended on the calibrations used in EDXRF. Empirical calibrations gave excellent agreement for percentage P, K and Ca, but moderate agreement for percentage Mg due to a weaker correlation between standards and intensities. Standardless calibration using the fundamental parameters (FP) approach exhibited bias, with consistently lower values reported for percentage P and Mg, when compared with ICP-OES methods. The relationship between the methods was plotted as scatter plots with the line of equality included, and although correlation coefficients indicated strong relationships, these statistics masked the effects of consistent bias in the data for percentage P and Mg. These results highlight the importance of distinguishing agreement from correlation when using statistical methods to compare methods of analysis. Agreement estimates improved when a matching library of grass samples was added to the FP method. EDXRF is a comparable alternative to conventional methods for grass analysis when samples of similar matrix type are used as empirical standards or as a matching library.

scholarly journals Improvement and modification of energy-dispersive x-ray fluorescence method for determination of metal elements in cement leachates - chemometric approach

2020 ◽  
pp. 67-67
Author(s):  
Nevenka Mijatovic ◽  
Anja Terzic ◽  
Lato Pezo ◽  
Ljiljana Milicic ◽  
Dragana Zivojinovic
Keyword(s):  
Inductively Coupled Plasma ◽  
Chemical Elements ◽  
Certified Reference Materials ◽  
Optical Emission ◽  
Fluorescence Method ◽  
Energy Dispersive ◽  
Emission Spectrometry ◽  
X Ray ◽  
Inductively Coupled ◽  
Plasma Optical Emission Spectrometry

A modification of analytical procedure for energy-dispersive X-ray fluorescence (EDXRF) quantification of ten chemical elements (As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Zn) in the leachates obtained from cement binders was developed. Twenty-nine testing samples were used in the experiment. All samples were based on Portland cement. Fly ash of different origin, zeolite and bentonite were employed as mineral additives in the cement binders. Distilled water was used as leachate. Validation of the modified EDXRF procedure was conducted in terms of limits of detection and quantification, working range, linearity, selectivity, precision, trueness, and robustness. Traceability of the procedure was established using certified reference materials. Uncertainty of measurement was confirmed via ?in-house? laboratory validation approach. The expanded uncertainties for ten analysed elements were obtained for entire working range of EDXRF method. Robustness of the modified EDXRF procedure was assessed by means of chemometric in-house approach. The results obtained by modified X-ray fluorescence method were additionally correlated to those acquired by inductively coupled plasma optical emission spectrometry to confirm that EDXRF can be used as an effective and reliable alternative method for analysis of cement leachates.

Preparation And elemental analysis of ancient fibers

1987 ◽  
Vol 45 ◽  
pp. 410-411
Author(s):  
Allen Angel ◽  
Kathryn A. Jakes
Keyword(s):  
Cross Sections ◽  
Physical Structure ◽  
Energy Dispersive ◽  
Archaeological Sites ◽  
X Ray ◽  
Long Term Storage ◽  
Backscattered Electron ◽  
Electron Imaging

Fabrics recovered from archaeological sites often are so badly degraded that fiber identification based on physical morphology is difficult. Although diagenetic changes may be viewed as destructive to factors necessary for the discernment of fiber information, changes occurring during any stage of a fiber's lifetime leave a record within the fiber's chemical and physical structure. These alterations may offer valuable clues to understanding the conditions of the fiber's growth, fiber preparation and fabric processing technology and conditions of burial or long term storage (1).Energy dispersive spectrometry has been reported to be suitable for determination of mordant treatment on historic fibers (2,3) and has been used to characterize metal wrapping of combination yarns (4,5). In this study, a technique is developed which provides fractured cross sections of fibers for x-ray analysis and elemental mapping. In addition, backscattered electron imaging (BSI) and energy dispersive x-ray microanalysis (EDS) are utilized to correlate elements to their distribution in fibers.

Evaluation on determination of iodine in coal by energy dispersive X-ray fluorescence

2005 ◽  
Vol 39 (4) ◽  
pp. 391-394 ◽  
Author(s):  
Binbin Wang ◽  
John C. Jackson ◽  
Curtis Palmer ◽  
Baoshan Zheng ◽  
Robert B. Finkelman
Keyword(s):  
Energy Dispersive ◽  
X Ray
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