Petre Osiceanu

Bio: Petre Osiceanu is an academic researcher from Romanian Academy. The author has contributed to research in topics: X-ray photoelectron spectroscopy & Thin film. The author has an hindex of 16, co-authored 86 publications receiving 892 citations.

Acid–base properties of the active sites responsible for C2+ and CO2 formation over MO–Sm2O3 (M = Zn, Mg, Ca and Sr) mixed oxides in OCM reaction

Abstract: The research investigates the quantitative relationship between the surface basicity of MO–Sm 2 O 3 (M = Zn, Mg, Ca and Sr) mixed oxides and catalytic activity for C 2 + formation. The amount as well as the evolution of surface carbonate species with nature of MO and reaction temperature were analyzed by XRD, TPD, XPS and IR methods to better understand the reaction mechanism. The concentration of surface basic sites responsible for the formation of C 2 + were found to correlate well with the amount of evolved CO 2 in the 300–800 °C temperature range. According to the experimental data, the higher was the catalyst basicity in terms of CO 2 retaining capacity the better was the efficiency for selectively converting methane to C 2 + . The turnover frequency (TOF) values were calculated by measuring the total number basic sites retaining reversible CO 2 in reaction conditions. The experimental results can be explained in a simplified manner by considering a reaction mechanism in which alkaline active sites play a crucial role in methane selective activation to C 2 + whereas the acidic sites, showing little interaction CO 2 , are responsible for methane combustion. A strategy for improving the performances of OCM catalysts is discussed in light of the experimental results.

Chemical solution deposition and characterization of BiFeO3 thin films

Abstract: One of the most interesting category of multifunctional systems is the magnetoelectrics (ME), i.e., materials having simultaneous magnetic and ferroelectric activity. The present paper describes a simple low-temperature synthesis method of preparing bismuth ferrite thin films by a wet chemical route, using bismuth and iron nitrates and two chelating agents (citric acid and polyvinyl alcohol). The films were layer by layer deposited on substrate (silica glass) using the dip-coating technique. The thickness of the layers were controlled by viscosity of the solutions and withdrawing speed parameters. After specific annealing, in air, the samples were characterized by scanning electron microscopy SEM, spectroelipsometry SE, X-ray photoelectron spectroscopy XPS, Raman spectroscopy. A more thoroughly control of the processing parameters seems to be essential in obtaining BiFeO 3 thin films. Solution chemistry variations (differences in precursor type) can have a significant impact on the film properties.

Recent progress in electrocatalysts and electrodes for portable fuel cells

Abstract: Fuel cells are devices that transform efficiently the chemical energy of hydrogen or another fuel into clean electricity. The fuel cell technology is attractive for its high-energy efficiency and expanded fuel flexibility and it became very relevant in the last decade. Moreover, the utilization of fuel cells for portable electronic devices has seen remarkable increase in the last few years. Performances of fuel cells, among others, strongly depend on the types of electrocatalysts and membrane, anion exchange or cation exchange, used in the system. Therefore, a status report about the latest advances in electrocatalysts and electrodes for portable fuel cells is the objective of this review paper. Herein, the recent progress in designing electrocatalysts for producing high performance fuel cells with truly potential applicability to be used in portable devices is highlighted.

Sustainable carbon materials

Abstract: Carbon-based structures are the most versatile materials used in the modern field of renewable energy (i.e., in both generation and storage) and environmental science (e.g., purification/remediation). However, there is a need and indeed a desire to develop increasingly more sustainable variants of classical carbon materials (e.g., activated carbons, carbon nanotubes, carbon aerogels, etc.), particularly when the whole life cycle is considered (i.e., from precursor "cradle" to "green" manufacturing and the product end-of-life "grave"). In this regard, and perhaps mimicking in some respects the natural carbon cycles/production, utilization of natural, abundant and more renewable precursors, coupled with simpler, lower energy synthetic processes which can contribute in part to the reduction in greenhouse gas emissions or the use of toxic elements, can be considered as crucial parameters in the development of sustainable materials manufacturing. Therefore, the synthesis and application of sustainable carbon materials are receiving increasing levels of interest, particularly as application benefits in the context of future energy/chemical industry are becoming recognized. This review will introduce to the reader the most recent and important progress regarding the production of sustainable carbon materials, whilst also highlighting their application in important environmental and energy related fields.

Durability Investigation of Carbon Nanotube as Catalyst Support for Proton Exchange Membrane Fuel Cell Electrode

Abstract: Abstract Electrochemical surface oxidation of carbon black Vulcan XC-72 and multiwalled carbon nanotube (MWNT) has been compared following potentiostatic treatments up to 168 h under condition simulating PEMFC cathode environment (60 °C, N2 purged 0.5 M H2SO4, and a constant potential of 0.9 V). The subsequent electrochemical characterization at different treatment time intervals suggests that MWNT is electrochemically more stable than Vulcan XC-72 with less surface oxide formation and 30% lower corrosion current under the investigated condition. As a result of high corrosion resistance, MWNT shows lower loss of Pt surface area and oxygen reduction reaction activity when used as fuel cell catalyst support.

"Clicking" polymers or just efficient linking: What is the difference?

Abstract: The "click" trick: Many reactions are classified as click reactions even though some are limited to certain applications. Thus, there is danger that the term "click" will become meaningless over time and simply a synonym for "successful". To prevent this, the original click criteria are evaluated in this Essay specifically for the synthetic polymer field and a set of criteria are specified that distinguishes click from other efficient reactions. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.