tailieunhanh - Báo cáo hóa học: " Silver Nanoparticles and Graphitic Carbon Through Thermal Decomposition of a Silver/Acetylenedicarboxylic Salt"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Silver Nanoparticles and Graphitic Carbon Through Thermal Decomposition of a Silver/Acetylenedicarboxylic Salt | Nanoscale Res Lett 2009 4 1358-1364 DOI s11671-009-9405-8 NANO EXPRESS Silver Nanoparticles and Graphitic Carbon Through Thermal Decomposition of a Silver Acetylenedicarboxylic Salt Panagiotis Dallas Athanasios B. Bourlinos Philomela Komninou Michael Karakassides Dimitrios Niarchos Received 24 March 2009 Accepted 20 July 2009 Published online 17 September 2009 to the authors 2009 Abstract Spherically shaped silver nanoparticles embedded in a carbon matrix were synthesized by thermal decomposition of a Ag I acetylenedicarboxylic acid salt. The silver nanoparticles which are formed either by pyrolysis at 300 C in an autoclave or thermolysis in xylene suspension at reflux temperature are acting catalytically for the formation of graphite layers. Both reactions proceed through in situ reduction of the silver cations and polymerization of the central acetylene triple bonds and the exact temperature of the reaction can be monitored through DTA analysis. Interestingly the thermal decomposition of this silver salt in xylene partly leads to a minor fraction of quasicrystalline silver as established by HR-TEM analysis. The graphitic layers covering the silver nanoparticles are clearly seen in HR-TEM images and furthermore established by the presence of sp2 carbon at the Raman spectrum of both samples. Keywords Silver nanoparticles Graphitization Acetylenedicarboxylic acid Nanocomposites P. Dallas A. B. Bourlinos D. Niarchos Institute of Materials Science NCSR Demokritos 15310 Athens Greece e-mail dallas@ dallas@ panosdallas@ A. B. Bourlinos e-mail bourlinos@ P. Komninou Department of Physics Aristotle University of Thessaloniki Thessaloniki Greece M. Karakassides Department of Materials Science and Engineering University of Ioannina Ioannina Greece Introduction Acetylenedicarboxylic acid ACD as carboxylic acids with short aliphatic chains 1 is well known to form complexes with transition metals such as Cd II 2