Highly efficient and reusable CNT supported iron(II) catalyst for microwave assisted alcohol oxidation

The highly efficient eco-friendly synthesis of ketones (yields over 99%) from secondary alcohols is achieved by combination of [FeCl2{eta(3)-HC(pz)(3)}] (pz = pyrazol-1-yl) supported on functionalized multi-walled carbon nanotubes and microwave irradiation, in a solvent-free medium. The carbon homoscorpionate iron(II) complex is the first one of this class to be used as catalyst for the oxidation of alcohols

Homogeneous and heterogenised new gold C-scorpionate complexes as catalysts for cyclohexane oxidation

Gold(III) complexes of type [AuCl2{eta(2)-RC(R'pz)(3)}]Cl [R = R' = H (1), R = CH2OH, R' = H (2) and R = H, R' = 3,5-Me-2(3), pz = pyrazol-1-yl] were supported on carbon materials (activated carbon, carbon xerogel and carbon nanotubes) and used for the oxidation of cyclohexane to cyclohexanol and cyclohexanone, with aqueous H2O2, under mild conditions

Facile one-pot synthesis of Pt nanoparticles/SBA-15: an active and stable material for catalytic applications

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Pt/SBA-15 with an enhanced surface area but unchanged pore diameter (compared to pure SBA-15) and a Pt average particle size of ∼9 nm shows a high and stable activity for both gas-phase CO oxidation and liquid-phase cyclooctadiene hydrogenation. No intrinsic change in the structure of the catalyst occurs after several reaction cycles, suggesting that the Pt/SBA-15 presented here is an active and stable catalyst.DFG, EXC 314, Unifying Concepts in Catalysi

The effect of nanotube surface oxidation in the electrical response of MWCNT/PVDF nanocomposites

Carbon nanotubes / poly(vinylidene fluoride) composites were prepared using CNT with different oxidation and thermal treatments. The oxidation procedure leads to CNT with the most acidic characteristics that lower the degree of crystallinity of the polymer and contribute to a large increase of the dielectric constant. The surface treatments, in general, increase percolation threshold and decrease conductivity, but, on the other hand, are able to promote the nucleation of the electroactive phase of the polymer, which is suitable for the use of PVDF in sensors, actuators and other smart materials applications. Finally, the surface treatments do not seem to affect CNT interaction among them, reaching similar degrees of dispersion in all cases, as shown by the SEM results. The maximum value of the dielectric constant is ~630. It is demonstrated that the composite conductivity can be attributed to a hopping mechanism that is strongly affected by the surface treatment of the CNT.The authors thank the Fundacao para a Ciencia e a Tecnologia (FCT), Portugal, for financial support through the projects PTDC/CTM/69316/2006 and NANO/NMed-SD/0156/2007), and CIENCIA 2007 program for S.A.C.; V. S., J.S. and J.N.P. also thank FCT for the SFRH/BPD/63148/2009, SFRH/BD/60623/2009 and SFRH/BD/66930/2009 grants

Catalysis by Metal-Oxide Nanostructures

Funding Information: This work received support from Portuguese national funds (FCT/MCTES, Fundação para a Ciência e Tecnologia and Ministério da Ciência, Tecnologia e Ensino Superior) through projects DOIs: 10.54499/LA/P/0008/2020, 10.54499/UIDP/50006/2020, 10.54499/UIDB/50006/2020. SACC also acknowledges FCT for the Scientific Employment Stimulus—Institutional Call (DOI 10.54499/CEECINST/00102/2018/CP1567/CT0026).publishersversionpublishe

Advances in Supported Nanoparticle Catalysts

Associate Laboratory for Green Chemistry- LAQV financed by national funds from FCT/MCTES (UIDP/5006/2020).publishersversionpublishe

Catalytic Oxidation of Hydrocarbons

SACC is grateful to Fundação para a Ciência e a Tecnologia (FCT), Portugal for Scientific Employment Stimulus-Institutional Call (DOI 10.54499/CEECINST/00102/2018/CP1567/CT0026) and to the Associate Laboratory for Green Chemistry-LAQV financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/5006/2020).publishersversionpublishe

Effect of different carbon materials as electron shuttles in the anaerobic biotransformation of nitroanilines

Aromatic amines resulted from azo dyes biotransformation under anaerobic conditions are generally recalcitrant to further anaerobic degradation. The catalytic effect of carbon materials (CM) on the reduction of azo dyes is known and has been confirmed in this work by increasing 3-fold the biological reduction rate of Mordant Yellow 1 (MY1). The resulting m-nitroaniline (m-NoA) was further degraded to m-phenylenediamine (m-Phe) only in the presence of CM. The use of CM to degraded anaerobically aromatic amines resulted from azo dye reduction was never reported before. In the sequence, we studied the effect of different CM on the bioreduction of o-, m- and p-NoA. Three microporous activated carbons with different surface chemistry, original (AC0), chemical oxidized with HNO3 (ACHNO3) and thermal treated (ACH2), and three mesoporous carbons, xerogels (CXA and CXB) and nanotubes (CNT) were assessed. In the absence of CM, NoA were only partially reduced to the corresponding Phe, whereas in the presence of CM, more than 90% was converted to the corresponding Phe. ACH2 and AC0 were the best electron shuttles, increasing the rates up to 8-fold. In 24h, the biological treatment of NoA and MY1 with AC0, decreased up to 88% the toxicity towards a methanogenic consortium, as compared to the non-treated solutions. This article is protected by copyright. All rights reservedR. Pereira holds a fellowship (SFRH/BD/72388/2010) from Fundação para a Ciência e Tecnologia (FCT). The authors thank the FCT Strategic UID/BIO/ 04469/2013 and exploratory EXPL/AAG-TEC/0898/2013 projects