Ceria nanoparticles as promoters of CO2 electroreduction on Ni YSZ An efficient preparation strategy and insights into the catalytic promotion mechanism

Since many decades nickel yttria stabilized zirconia cermet Ni YSZ has been the most frequently used fuel electrode material for high temperature solid oxide cells SOCs . However, in recent years there has been considerable effort to improve the Ni YSZ performance through surface engineering. In this work, we report a simple strategy to apply nanosized un doped CeOx and Ni doped NiCeOy ceria particles into porous Ni YSZ cermet electrodes via infiltration from hexane solution. Detailed characterization of the particles in their solution revealed differences in the ease of agglomeration, with NiCeOy nanoparticles being better dispersed and thus forming smaller aggregates. This property is critical for the effectiveness of the solution in filling the pores of Ni YSZ cermet and the consequent ceria deposition. In particular, morphological and microstructural characterization reveals that NiCeOy nanoparticles decorate uniformly the pores of Ni YSZ backbone, deep up to the interface with the electrolyte. More importantly, this can be done with relatively high ceria loading per infiltration co firing step. Electrochemical tests demonstrate that infiltrated Ni YSZ fuel electrodes have improved I V performance in CO2 electrolysis as compared to pristine Ni YSZ. Synchrotron based operando NAP XPS experiments using both soft and tender X rays revealed the formation of an ultrathin Ni Ce3 layer on the electrode surface, which can rationalize the ameliorated CO2 electrolysis performanc

A highly N-doped carbon phase "dressing" of macroscopic supports for catalytic applications

© The Royal Society of Chemistry 2015. The straightforward "dressing" of macroscopically shaped supports (i.e. β-SiC and α-Al2O3) with a mesoporous and highly nitrogen-doped carbon-phase starting from food-processing raw materials is described. The as-prepared composites serve as highly efficient and selective metal-free catalysts for promoting industrial key-processes at the heart of renewable energy technology and environmental protection

Synthesis of Well-Defined, Surfactant-Free Co₃O₄ Nanoparticles:The Impact of Size and Manganese Promotion on Co₃O₄ Reduction and Water Oxidation Activity

Abstract: A surfactant-free synthetic route has been developed to produce size-controlled, cube-like cobalt oxide nanoparticles of three different sizes in high yields. It was found that by using sodium nitrite as salt-mediating agent, near-quantitative yields could be obtained. The size of the nanoparticles could be altered from 11 to 22 nm by changing the cobalt concentration and reaction time. These surfactant-free nanoparticles form ideal substrates for facile deposition of further elements such as manganese. The effect of size of the cobalt oxide nanoparticles and the presence of manganese on the reducibility of cobalt oxide to metallic cobalt was investigated. Similarly, the effect of these parameters was investigated with a visible light promoted water oxidation system with cobalt oxide as catalyst, together with [Ru(bpy) 3] 2+ light harvester dye and an electron acceptor. Graphical Abstract: A novel surfactant-free synthetic route has been developed to produce size-controlled, cube shaped cobalt oxide nanoparticles in high yields. [Figure not available: see fulltext.]. </p

Geographical differentiation of cephalometric data of a nomadic isolated Hellenic population (Sarakatsani)

The scientific value of isolated human populations is important for the understanding of ethnic formation, or for micro-evolution. The population of Sarakatsani in HELLAS was nomadic up to 10-15 years ago. It may still be considered as nomadic since it migrates during winter and summer. We studied three Sarakatsanic groups, geographically isolated in Epirus, Central Macedonia and Peloponessos. Nine cephalometric variables were measured and subjected to Discriminant Function Analysis (DFA) and Analysis of Variance (ANOVA). The latter showed that 55% of the variables indicate a statistically significant difference. The former showed that only the Peloponesean population is well differentiated. The groups from Epirus and Macedonia differentiated between them less, compared to the Peloponesean group. © 1994 International Institute for the Study of Man

Geographical differentiation of cephalometric data of a nomadic isolated Hellenic population (Sarakatsani)

The scientific value of isolated human populations is important for the understanding of ethnic formation, or for micro-evolution. The population of Sarakatsani in HELLAS was nomadic up to 10-15 years ago. It may still be considered as nomadic since it migrates during winter and summer. We studied three Sarakatsanic groups, geographically isolated in Epirus, Central Macedonia and Peloponessos. Nine cephalometric variables were measured and subjected to Discriminant Function Analysis (DFA) and Analysis of Variance (ANOVA). The latter showed that 55% of the variables indicate a statistically significant difference. The former showed that only the Peloponesean population is well differentiated. The groups from Epirus and Macedonia differentiated between them less, compared to the Peloponesean group. © 1994 International Institute for the Study of Man

TYPES OF SUPERNUMERARY OUTGROWTHS PRODUCED AFTER INVERTING THE DORSOVENTRAL LIMB AXIS OF THE ANURAN BUFO-BUFO

Contralateral grafts were performed on the larval limb buds of the anuran Bufo bufo. The dorsoventral axis of 80 buds at stages IV or V was inverted. Ten tadpoles were used as controls. Fifty-two supernumerary structures developed, all of them in dorsal or ventral locations on the host stump. The majority (32 out of the 44 outgrowths with more than 3 toes) were normal limbs of stump handedness. However, the following abnormal structures were also observed: 2 double-posterior, 3 mixed-symmetric, and 7 undetermined cases. These results are in agreement with the predictions of a hierarchical polar coordinate model for epimorphic regeneration

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