In situ X-rays

Koop T, Schindler W, Kazimirov A, Scherb G, Zegenhagen J, Schulz T, Feidenhans l R and Kirschner J 1998 Electrochemical cell tor in situ x-ray diffraction under ultrapure conditions Rev. Sc/, instrum. 69 1840... 

Wu S, Lipkowski J, Tyiiszczak T and Hitchcock A P 1997 Eariy stages of copper eiectrocrystaiiization eiectrochemicai and in situ x-ray absorption fine structure studies of coadsorption of copper and chioride at the Au(111) eiectrode surface J.Phys. Chem. B 101 10 310-22... 

Li J and Abruna FI D 1997 Coadsorption of sulphate/bisulphate anions with Fig cations during Fig underpotential deposition on Au (111) An In situ x-ray diffraction study J. Phys. Chem. B 101 244-52... 

Suzuki, T. and Kaneko, K., Structural change of activated carbon fibers with desorption by in situ x-ray diffraction. Carbon, 1988, 26(5), 744 745. 

Fig. 8.5 Sections of [in situ) X-ray powder patterns of a-Ca3(BN2)2 with the 220 reflection and -Ca3(BN2)2 with 200, 224, and 400 reflections. (Low-temperature) y -Ca3(BN2)2 is obtained on slow cooling...

The reaction on the catalyst surface was followed by in situ i.r. spectroscopy using a Bruker IFS88 FTIR spectrometer for the characterisation of sorbed species and mass spectroscopy for the analysis of gas phase. The state of Pt was further investigated by in situ X-ray absorption spectroscopy (Daresbury, UK, beamline 9.1, transmission mode, Si(220) monochromator, Pt-Lj, edge). Details of catalyst characterisation techniques are reported elsewhere [13,14]. 

FIGURE 27.12 In situ X-ray absorption spectra for a Cu full layer obtained in sulfate solution at 0.2 V (SCE) parallel (a) and perpendicular (b) polarizations. (From Soldo et al., 2002, with permission from Elsevier.)... 

However, it should be noted that the structure of those bimetallic particles (Ag-In) can be changed under the conditions of the catalytic reaction, that is, in presence of the reactants, as recently shown by in situ X-ray absorption spectroscopy of acrolein hydrogenation [100]. 

Experimentally, different structure- and surface-sensitive techniques such as in situ scanning tunnelling microscopy (STM), in situ X-ray diffraction (XRD), transition electron microscopy (TEM), and in situ infrared (IR) spectroscopy have been... 

You H, Zurawski DJ, Nagy Z, Yonco RM. 1994. In-situ X-ray reflectiyity study of incipient oxidation of Pt(lll) surface in electrol)Te-solutions. J Chem Phys 100 4699-4702. 

Lucas CA, Markovic NM. 2006. In-situ X-ray diffraction studies of the electrode/solution interface. In AUdre RC, Kolb DM, Lipkowski J, Ross PN, editors. Advances in Electrochemical Science and Engineering. Volume 9. New York Wiley-VCH, pp. 1-45. 

Ocko BM, Wang J, Davenport A, Isaacs H. 1990. In situ X-ray reflectivity and diffi action studies of the Au(OOl) reconstruction in an electrochemical cell. Phys Rev Lett 65 1466-1469. 

Tidswell IM, Markovic NM, Lucas C, Ross PN. 1993. In-situ X-ray scattering study of the Au(lOO) reconstructuin in alkaline and acid solution. Phys Rev B 47 16542. 

Wang JX, Marinkovic NS, Zajonz H, Ocko BM, Adzic RR. 2001. In situ X-ray reflectivity and voltammetry study of Ru(OOOl) surface oxidation in electrol3de solutions. J Phys Chem B 105 2809-2814. 

The effects of tin/palladium ratio, temperatnre, pressnre, and recycling were studied and correlated with catalyst characterization. The catalysts were characterized by chemisorption titrations, in situ X-Ray Diffraction (XRD), and Electron Spectroscopy for Chemical Analysis (ESCA). Chemisorption studies with hydrogen sulfide show lack of adsorption at higher Sn/Pd ratios. Carbon monoxide chemisorption indicates an increase in adsorption with increasing palladium concentration. One form of palladium is transformed to a new phase at 140°C by measurement of in situ variable temperature XRD. ESCA studies of the catalysts show that the presence of tin concentration increases the surface palladium concentration. ESCA data also indicates that recycled catalysts show no palladium sulfide formation at the surface but palladium cyanide is present. 

Figure 19. In situ X-ray absorption spectrum for a copper upd monolayer on a gold (111) electrode with the polarization of the X-ray beam being perpendicular (A) or parallel (B) to the electrode surface.

Figure 27. In situ X-ray absorption spectra around the ruthenium X-edge for an electrode modified with (A) one and (B) five monolayers of [Ru(v-bpy)3]2+. (C) Spectrum of bulk [Ru(bpy)3]2+.

Figure 28. In situ X-ray absorption of the near-edge region for an electrode modified with a polymeric film of [Ru(v-bpy)3]2+ and its potential dependence. Applied potentials were +0.7 V (A) and + 1.5 V (B).

Figure 35. Electrochemical cell for in situ X-ray standing wave measurements. (From Ref. 120, with permission.)...

A number of surface diffraction techniques can be employed in the structural study of electrochemical interfaces, depending on the details of the system under study. For bulk materials or thick films (such that the X-ray beam only samples that layer) conventional diffraction experiments can be performed and, in fact, a number of in situ X-ray diffraction studies of this type have been reported.126 129 In the case of thin films or monolayers, two different techniques can be employed and these are the reflection-diffraction technique introduced by Marra and Eisenberger,3 ), 32 and the technique based on surface truncation rods.131 In the first case, the incident X-ray beam impinges on the sample at an angle below... 

In this paper we present results from independent studies on the stage 2 to stage 1 transition area that show some unexpected features (anomalies). The results are obtained by electrochemical impedance spectroscopy (EIS), entropy measurements (AS(x)) and in situ x-ray diffractometry (XRD). The aim is to understand the mechanism of stage transition dealing with the observed anomalies. 

In-situ x-ray diffraction (XRD) was performed on a coin type cell with a 4x6 mm Kapton window coated with conductive thin copper layer. The graphite electrode was pressed against the Kapton window so as to be reached by the x-ray beam. After several lithiation/delithiation cycles under a C/10 rate between 1.5 and 0V, the cell was fully delithiated up to 1.5V. The cycle capacity achieved with the graphite electrode is about 360mAh/g. The cell was then re-lithiated under a slower rate of C/20. XRD patterns were taken for about five minutes every hour while the cell is under continuous discharge. As result the lithium composition x in LixC6 was incremented by 0.05 between two successive XRD scans. 

Fransson L. M. L, Vaughey J. T., Benedek R., Edstrom K., Thomas J. O., Thackeray M. M., Phase transitions in lithiated Cu2Sb anodes for lithium batteries an in situ X-ray diffraction study, Electrochem. Commun., (2001) 3 (7), 317-323. 

Figure 2.81 (a) Schematic of the system for in situ X-ray reflectivity measurements. Syn = synchrotron source M = monochromator S = slit /0, /R = incident and reflected X-rays beams, respectively 9 = angle of incidence W = teflon windows WE = working electrode RE = reference electrode CF = counter electrode D = scintillation detector, (h) Cyclic voltammogram of Cu-on-Si electrode in borate buffer solution (pH 8.4), scan rate = lOmVs-1. From Melendres... 

It has been observed that cobalt may undergo large-scale reconstruction under a synthesis gas environment.27 Reconstruction is a thermodynamically driven process that results in the stabilization of less reactive surfaces. Recent molecular modeling calculations have shown that atomic carbon can induce the clock reconstruction of an fee cobalt (100) surface.28 It has also been postulated and shown with in situ x-ray adsorption spectroscopy (XAS) on cobalt supported on carbon nanofibers that small particles (<6 nm) undergo a reconstruction during FTS that can result in decreased activity.29... 

Lee et al. [30] used in situ X-ray photo electron spectroscopy (XPS) measurement on La0 9Sr0 Mn03 as a function of cathodic polarization. The XPS results showed the peaks of Mn 2p spectra were shifted to the lower binding energy as the applied potential became more cathodic, indicating the reduction of Mn ions. The oxygen reduction and the concomitant formation of Mn2+ ions and oxygen vacancies are proposed as ... 

Aspects of X-ray diffraction on single spider fibres. Int.J. Biol. Macromol. 24,179-186. Riekel, C., Mueller, M., and Vollrath, F. (1999b). In situ X-ray diffraction during forced silking of spider silk. Macromolecules 32, 4464-4466. 

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