01619nas a2200229   4500008004100000022001400041245012400055210006900179260007700248300001000325490000600335520074600341653001501087653001301102653001401115653001401129653002101143100003001164700003201194700003201226856013101258       2009                        eng d  a1861-472800aKinetic evidence for the influence of subsurface oxygen on palladium surfaces towards CO oxidation at high temperatures0 aKinetic evidence for the influence of subsurface oxygen on palla  aPO BOX 10 11 61, D-69451 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcOCT  a74-800 v43 a<p>Transient state kinetics of the catalytic oxidation of CO with 0, on Pd-surfaces has been measured under isothermal conditions by using a molecular beam approach. Systematic studies were carried out as a function of reaction temperature and CO+O(2) composition. With sufficient kinetic evidence, we have demonstrated the positive influence of subsurface oxygen towards CO-adsorption and oxidation to CO, at high temperatures (600-900 K) on Pd-surfaces, and the likely electronic nature of the surface changes with oxygen in the subsurface. These studies also provide a direct proof for CO-adsorption with a significantly reactive sticking coefficient at high temperatures on Pd-surfaces exhibiting a significant subsurface O-coverage.</p>10aAdsorption10akinetics10aOxidation10aPalladium10asurface analysis1 aGopinath, Chinnakonda, S.1 aThirunavukkarasu, Kandasamy1 aNagarajan, Sankaranarayanan  uhttps://library.ncl.res.in/content/kinetic-evidence-influence-subsurface-oxygen-palladium-surfaces-towards-co-oxidation-high-001608nas a2200217   4500008004100000022001400041245010200055210006900157260007700226300001200303490000600315520081200321653002801133653001301161653001101174653001401185653002201199100001501221700003001236856012401266       2014                        eng d  a1867-388000aNOx reduction at near ambient temperatures and under lean-burn conditions on modified pd surfaces0 aNOx reduction at near ambient temperatures and under leanburn co  aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcFEB  a531-5370 v63 a<p>Palladium surfaces that are modified with O atoms in the subsurface broaden the NO reduction temperature regime up to 325 K with O-2-rich NO+H-2+O-2 compositions. Compared to virgin Pd surfaces, up to 150% higher deNO(x) catalytic activity was observed with modified Pd surfaces at the reaction maximum. Molecular beam instrument and ambient-pressure photoelectron spectroscopy were employed to follow the kinetic and surface changes. These results open up a possibility to realize the cold-start reduction of NOx (deNO(x)). DeNO(x) activity reported in the literature with supported Pd catalysts after a simple calcination in air compares well with our present observations. Surface modification is likely to demonstrate a high potential for other catalytic reactions at relatively low temperatures.</p>10aheterogeneous catalysis10anitrogen10aoxygen10aPalladium10asurface chemistry1 aRoy, Kanak1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/nox-reduction-near-ambient-temperatures-and-under-lean-burn-conditions-modified-pd-002870nas a2200265   4500008004100000022001400041245014500055210006900200260007100269300001400340490000600354520191100360653001202271653002802283653001302311653001402324653001902338653001702357653001402374653002502388100001502413700001602428700003002444856013002474       2014                        eng d  a2155-543500aTowards a sustainable and near ambient DeNO(x) under lean burn conditions: a revisit to no reduction on virgin and modified pd(111) surfaces0 aTowards a sustainable and near ambient DeNOx under lean burn con  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUN  a1801-18110 v43 a<p>Catalytic conversion of NO in the presence of H-2 and O-2 has been studied on Pd(111) surfaces, by using a molecular beam instrument with mass spectrometry detection, as a function of temperature and reactants composition. N-2 and H2O are the major products observed, along with NH3 and N2O minor products under all conditions studied. Particular attention has been paid to the influence of O-2 addition toward NO dissociation. Although O-2-rich compositions were found to inhibit the deNO(x) activity of the Pd catalyst, some enhancement in NO reduction to N-2 was also observed up to a certain O-2 content. The reason for this behavior was determined to be the effective consumption of the H-2 in the mixture by the added O-2 and O atoms from NO dissociation. NO was proven to compete favorably against O-2 for the consumption of H-2, especially &lt;= 550 K, to produce N-2 and H2O. Compared with other elementary reaction steps, a slow decay observed with the 2H + 0 -&gt; H2O step under SS beam oscillation conditions demonstrates its contribution to the rate-limiting nature of the overall reaction. Pd(111) surfaces modified with O atoms in the subsurface (Md-Pd(111)) induces steady-state NO reduction at near-ambient temperatures (325 K) and opens up a possibility to achieve room temperature emission control. A 50% increase in the reaction rates was observed at the reaction maximum on Md-Pd(111), as compared with virgin surfaces. Oxygen adsorption is severely limited below 400 K, and effective NO + H-2 reaction occurs on Md-Pd(111) surfaces. Valence band photoemission with a UV light source (He I) under different oxygen pressures with APPES clearly identified the characteristics of the Md-Pd(111) surfaces and PdO. The electron-deficient or cationic nature of Md-Pd(111) surfaces enhances the NO dissociation and inhibits oxygen chemisorption &lt;= 400 K under lean-burn conditions.</p>10adeNO(x)10aheterogeneous catalysis10aHydrogen10alean burn10amolecular beam10anitric oxide10aPalladium10asurface modification1 aRoy, Kanak1 aJain, Ruchi1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/towards-sustainable-and-near-ambient-denox-under-lean-burn-conditions-revisit-no-reduction02539nas a2200289   4500008004100000022001400041245014400055210006900199260000900268300001600277490000700293520157100300653002101871653001301892653001901905653001301924653001401937653000801951100002301959700002101982700001802003700002302021700001902044700002802063700003002091856012802121       2024                        eng d  a1944-824400aElectrocatalytic glycerol conversion: a low-voltage pathway to efficient carbon-negative green hydrogen and value-added chemical production0 aElectrocatalytic glycerol conversion a lowvoltage pathway to eff  cMAY   a26130-261410 v163 a<p>
	Electrochemical glycerol oxidation reaction (GLYOR) could be a promising way to use the abundantly available glycerol for production of value-added chemicals and fuels. Completely avoiding the oxygen evolution reaction (OER) with GLYOR is an evolving strategy to reduce the overall cell potential and generate value-added chemicals and fuels on both the anode and cathode. We demonstrate the morphology-controlled palladium nanocrystals, afforded by colloidal chemistry, and their established morphology-dependent GLYOR performance. Although it is known that controlling the morphology of an electrocatalyst can modulate the activity and selectivity of the products, still it is a relatively underexplored area for many reactions, including GLYOR. Among nanocube (Pd-NC), truncated octahedron (Pd-TO), spherical and polycrystalline (Pd-PC) morphologies, the Pd-NC electrocatalyst deposited on a Ni foam exhibits the highest glycerol conversion (85%) along with 42% glyceric acid selectivity at a low applied potential of 0.6 V (vs reversible hydrogen electrode (RHE)) in 0.1 M glycerol and 1 M KOH at ambient temperature. Owing to the much favorable thermodynamics of GLYOR on the Pd-NC surface, the assembled electrolyzer requires an electricity input of only similar to 3.7 kWh/m(3) of H-2 at a current density of 100 mA/cm(2), in contrast to the requirement of &gt;= 5 kWh/m(3) of H-2 with an alkaline/PEM electrolyzer. Sustainability has been successfully demonstrated at 10 and 50 mA/cm(2) and up to 120 h with GLYOR in water and simulated seawater.</p>
10aelectrocatalysis10aGlycerol10agreen hydrogen10ananocube10aPalladium10aSDG1 aChauhan, Inderjeet1 aBajpai, Himanshu1 aRay, Bishakha1 aKolekar, Sadhu, K.1 aDatar, Suwarna1 aPatra, Kshirodra, Kumar1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/electrocatalytic-glycerol-conversion-low-voltage-pathway-efficient-carbon-negative-green