@article { ISI:000264437500012, title = {Copper-based catalysts for water gas shift reaction: influence of support on their catalytic activity}, journal = {Catalysis Today}, volume = {141}, number = {1-2}, year = {2009}, note = {18th National Symposium and Indo-US Seminar on Catalysis, Indian Inst Petroleum, Dehradun, INDIA, APR 16-18, 2007}, month = {MAR}, pages = {72-76}, publisher = {Catalysis Soc India; Petrotech Soc; Indo US Sci \& Technol Forum}, type = {Article}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Three copper containing catalysts supported on ceria and mixed oxides of ceria with zirconia and titania were prepared by co-precipitation method and their catalytic activity was tested for water gas shift (WGS) reaction. High surface area (\>100m(2)/g) mixed oxides were obtained following the present method of preparation. The catalysts were characterized by XRD, H(2)-temperature programmed reduction (TPR), UV-vis and XPS. Catalytic activity was evaluated for water gas shift reaction in the 200-400 degrees C temperature range, The gas hourly space velocity was varied from 5000 to 25,000h(-1) for better evaluation and comparison of their performance. The effect of CO(2) in the feed gas mixture on the WGS activity of these catalysts was also studied. Among the three catalysts studied, CuO-CeO(2)-ZrO(2) mixed oxide shows better activity, implying the influence of support. Characterization of the catalysts after WGS reaction was also carried out in order to investigate structure-property correlation. (c) 2008 Elsevier B.V. All rights reserved.

}, keywords = {ceria, Ceria-titania, Ceria-zirconia, Co-precipitation, Copper, Water gas shift}, issn = {0920-5861}, doi = {10.1016/j.cattod.2008.06.026}, author = {Pradhan, S. and Reddy, A. Satyanarayana and Devi, R. N. and Chilukuri, Satyanarayana V.} } @article { ISI:000302893400028, title = {In situ encapsulation of ultra small ceria nanoparticles stable at high temperatures in the channels of mesoporous silica}, journal = {Microporous and Mesoporous Materials}, volume = {155}, year = {2012}, month = {JUN}, pages = {215-219}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Ultra small ceria nanoparticles of sizes \<2 nm stable at 500 degrees C are encapsulated in the channels of mesoporous silica by employing a novel method of synthesis. The method involves modifying non-ionic polymer templates with ionic surfactants to enhance anchoring of metal ion precursors. In this way, further silica wall formation around the template ensures isolation of the nanoparticles exclusively within the channels after template removal by heat treatment. Further understanding of the interaction of the composite template system and cerium precursor is gained by cyclic voltammetric studies. (C) 2012 Elsevier Inc. All rights reserved.

}, keywords = {ceria, Encapsulation, Mesoporous silica, Template synthesis}, issn = {1387-1811}, doi = {10.1016/j.micromeso.2012.02.006}, author = {Ghosh, Sumona and Jijil, Chamundi P. and Devi, R. Nandini} } @article { ISI:000353931300023, title = {Shape-selective oriented cerium oxide nanocrystals permit assessment of the effect of the exposed facets on catalytic activity and oxygen storage capacity}, journal = {ACS Applied Materials \& Interfaces}, volume = {7}, number = {16}, year = {2015}, month = {APR}, pages = {8545-8555}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

The catalytic performance of a range of nanocrystalline CeO2 samples, prepared to have different morphologies, was measured using two accepted indicators; oxygen storage and diesel soot combustion. The same powders were characterized hi detail by HR-TEM, XRD, XPS, and Raman methods. The study demonstrates that activity is determined by the relative fraction of the active crystallographic planes, not by the specific surface area of the powders. The physical study is a step toward quantitative evaluation of the relative contribution to activity of the different facets. The synthetic protocol permits fabrication of CeO2 nanostructures with preferentially grown active planes, and therefore has potential in developing catalytic applications and in nanocompositing.

}, keywords = {ceria, chemical activities, crystal facets, nanocrystals, texture coefficient}, issn = {1944-8244}, doi = {10.1021/acsami.5b00298}, author = {Sreeremya, Thadathil S. and Krishnan, Asha and Remani, Kottayilpadi C. and Patil, Kashinath R. and Brougham, Dermot F. and Ghosh, Swapankumar} } @article { ISI:000377891600014, title = {Direct synthesis of dimethyl carbonate from CO2 and methanol over CeO2 catalysts of different morphologies}, journal = {Journal of Chemical Sciences}, volume = {128}, number = {6}, year = {2016}, month = {JUN}, pages = {957-965}, publisher = {INDIAN ACAD SCIENCES}, address = {C V RAMAN AVENUE, SADASHIVANAGAR, P B \#8005, BANGALORE 560 080, INDIA}, abstract = {

The direct synthesis of dimethyl carbonate (DMC) from carbon dioxide (CO2) and methanol is an attractive approach towards conversion of the greenhouse gas - CO2 into value-added chemicals and fuels. Ceria (CeO2) catalyzes this reaction. But the conversion efficiency of CeO2 is enhanced when the byproduct water in the reaction medium is separated by employing trapping agents like 2-cyanopyridine (2-CP). In this work, the influence of morphology of CeO2 on the direct synthesis of DMC in presence of 2-CP is reported. CeO2 catalysts of cube, rod, spindle and irregular morphology (Ce - C, Ce - R, Ce - S and Ce - N, respectively) were prepared, characterized and studied as catalysts in the said reaction conducted in a batch mode. Among all, Ce - S shows superior catalytic performance with nearly 100 mol\% of DMC selectivity. Catalytic activity correlates with the concentration of acid and base sites of medium strength as well as defect sites. Ce - S has an optimum number of these active sites and thereby shows superior catalytic performance.

}, keywords = {acid-base catalysis, ceria, CO2 utilization, Dimethyl carbonate, influence of morphology}, issn = {0974-3626}, doi = {10.1007/s12039-016-1094-0}, author = {Unnikrishnan, P. and Darbha, Srinivas} } @article {48077, title = {Facile, sustainable and unassisted plain water oxidation on Au/Ce0.9Ti0.1O2 nanorods in direct sunlight}, journal = {Journal of Chemical Sciences}, volume = {134}, year = {2022}, month = {JUN}, pages = {61}, type = {Article}, abstract = {

Impressive rate of solar water oxidation to molecular oxygen (O-2) has been demonstrated on nanorods (NRs) of Ce0.9Ti0.1O2 (CT-NR) and Au-deposited CT-NR (Au-CT-NR) photocatalysts with a sacrificial agent (Fe3+) and in plain water in one sun condition, direct sunlight and with lambda \>= 455 nm. Probably the highest 0 2 yield of 11 mmol/h.g was observed with Au-CT-NR thin film in plain water in direct sunlight, with no sacrificial agent or applied potential. Photoelectrochemical measurements demonstrate a marked reduction in oxidation onset potential of Au-CT-NR by 150 mV with stable photocurrent (0.75 mA/cm(2)), compared to CT-NR (0.23 mA/cm(2)), indicating the operative of plasmon-induced resonant energy transfer (PIRET) process. Effective electron quenching by nanogold and hence low recombination in the depletion region is a critical step for the observation of a high rate of oxygen evolution. In addition to this, a predominant change in the nature of the valence band from O-2p dominated on CeO2 to Ce-4f dominated with CT-NR (due to Ti4+ introduction in CeO2), the efficient light absorption of photocatalysts in thin-film form, functional and effective PIRET process, and facile E-F alignment, enhances the oxygen evolution with Au-CT-NR in direct sunlight and make it highly sustainable. A possible mechanism of water oxidation is proposed from the observed experimental findings.

}, keywords = {ceria, Electronic integration, Photocatalysis, thin film, water splitting}, issn = {0974-3626}, doi = {10.1007/s12039-022-02055-z}, author = {Dubey, Anjani and Mishra, Abhaya Kumar and Negi, Sanjay Singh and Gopinath, Chinnakonda S.} }