@article { ISI:000312004800088, title = {Bulk and surface structure characterization of nanoscopic silver doped lanthanum chromites}, journal = {Applied Surface Science}, volume = {264}, year = {2013}, month = {JAN}, pages = {574-580}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Crystalline state of lanthanum chromites with silver as a dopant has been studied by X-ray diffraction and transmission electron microscopy reveals microscopic properties of grain boundaries. X-ray photoelectron spectroscopy has been used to analyze surface states with atomic ratio of La, Cr, O and Ag as a dopant. LaCrO3 shows mixed valence states of chromium while the silver doped samples exhibit differences in chromium concentration with the oxidation of Cr3+ to Cr6+ in presence of chromium nitrate as a precursor salt. Trivalent stable state of chromium is observed for samples synthesized by chromic acetate as a precursor salt. (C) 2012 Elsevier B.V. All rights reserved.

}, keywords = {Energy dispersive analysis of X-rays, Microwave combustion synthesis, Perovskite nanostructures, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy}, issn = {0169-4332}, doi = {10.1016/j.apsusc.2012.10.067}, author = {Desai, P. A. and Joshi, P. N. and Patil, K. R. and Athawale, Anjali A.} } @article {47319, title = {Boron nitride and oxide supported on dendritic fibrous nanosilica for catalytic oxidative dehydrogenation of propane}, journal = {ACS Sustainable Chemistry \& Engineering}, volume = {8}, year = {2020}, month = {NOV }, pages = {16124-16135}, type = {Article}, abstract = {

In this work, we were able to significantly increase the activity of boron nitride (BN) catalysts used for the oxidative dehydrogenation (ODH) of propane by designing and synthesizing BN supported on dendritic fibrous nanosilica (DFNS). DFNS/BN showed a markedly increased catalytic efficiency, accompanied by exceptional stability and selectivity. Textural characterization, together with solid-state nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopic analyses, indicates the presence of a combination of unique fibrous morphology of DFNS and various boron sites connected to silica to be the reason for this increase in the catalytic performance. Notably, DFNS/B2O3 also showed catalytic activity, although with more moderate selectivity compared to that of DFNS/BN. Solid-state NMR spectra indicate that the higher selectivity of DFNS/BN might stem from a larger amount of hydrogen-bonded hydroxyl groups attached to B atoms. This study indicates that both boron nitride and oxide are active catalysts and by using high surface area support (DFNS), conversion from propane to propene as well as productivity of olefins was significantly increased.

}, keywords = {Electron microscopy, heterogeneous catalysis, Nanostructures, NMR spectroscopy, propane dehydrogenation, X-ray diffraction, X-ray photoelectron spectroscopy}, issn = {2168-0485}, doi = {10.1021/acssuschemeng.0c04148}, author = {Belgamwar, Rajesh and Rankin, Andrew G. M. and Maity, Ayan and Mishra, Amit Kumar and Gomez, Jennifer S. and Trebosc, Julien and Vinod, Chathakudath P. and Lafon, Olivier and Polshettiwar, Vivek} } @article {48047, title = {Tuning of work function of ZnO by doping and co-doping: an investigation using X-ray photoelectron spectroscopy}, journal = {Thin Solid Films}, volume = {761}, year = {2022}, month = {NOV}, pages = {139538}, type = {Article}, abstract = {

The shift in the work function of the ZnO thin film upon varying codoping ratio has been investigated by X-ray photoelectron spectroscopy. A notable shift of 0.2 eV in the work function was achieved in the films when the Al: In doping ratio was changed from 0:10 to 10:0. The elemental composition of the dopants obtained from XPS analysis showed the presence of more amount of In dopant than Al in codoped ZnO films. In this way a clear understanding of the variation in electrical properties on dopant ratio is obtained. A decrease in work function was also observed with the increase in free carrier concentration when the codopant ratio is changed. The effects of Burstein moss, band narrowing, and band renormalization observed in the bandgap were explained by an upward and downward shift of valence band maxima of the corresponding thin films. The controllable work function of the codoped ZnO films by varying the doping ratio offers excellent potential advantages in optoelectronic devices.

}, keywords = {Indium -Aluminum co -doping, Spray coating, thin film, Work function, X-ray photoelectron spectroscopy, Zinc oxide}, issn = {0040-6090}, doi = {10.1016/j.tsf.2022.139538}, author = {Soumya, K. and Selvam, I. Packia and Vinod, C. P. and Potty, S. N.} } @article {48284, title = {Low-temperature preferential CO oxidation in a hydrogen-rich stream over Pt-NaY and modified Pt-NaY catalysts for fuel cell application}, journal = {Fuel Cells}, volume = {23}, year = {2023}, month = {FEB}, pages = {15-28}, type = {Article}, abstract = {

Preferential oxidation of CO (CO-PROX) in the hydrogen-rich stream has been carried out over Pt-NaY catalysts containing various Pt loadings along with Fe, Co, and Au. Catalysts have been characterized with inductively coupled plasma-atomic emission spectroscopy, Brunauer, Emmett, and Teller surface area, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, temperature programmed reduction, and Pt dispersion. CO-PROX activities and CO oxidation selectivities are observed to increase with an increase in Pt content. Pt-NaY catalyst with 0.75 wt.\% Pt loading shows maximum CO-PROX activity at low temperatures. An increase in space velocity decreases the CO and O-2 conversions, but CO oxidation selectivity increases. A decrease in activity is observed when reformat gas contains around 20\% H2O. During the stability test, no change in CO and O-2 conversions is observed, but a small increase in the CO oxidation selectivity is noticed after 10 h indicating that the Pt-NaY catalyst is a promising candidate for CO-PROX reaction in a hydrogen-rich stream. The Pt-Fe-NaY catalyst shows better activity than the Pt-NaY catalyst but starts deactivating after 10 h. However, activity is observed to decrease over Pt-Co-NaY and Pt-Au-NaY catalysts. Pt-Fe-NaY catalyst with 0.75 and 0.35 wt.\% Pt and Fe, respectively, shows better CO-PROX activity at a temperature of 75 degrees C.

}, keywords = {catalysis, CO oxidation, experimental results, flow bed, Fuel Cell Applications, Hydrogen, X-ray photoelectron spectroscopy}, issn = {1615-6846}, doi = {10.1002/fuce.202200134}, author = {Malwadkar, Sachin and Bera, Parthasarathi and Satyanarayana, Chilukuri V. V.} }