Authors:T. Braun, H. Rausch, L. Bíró, Z. Konya, and I. Kiricsi
By using instrumental neutron activation analysis (INAA) it has been shown that some pristine carbon SWNT's and MWNT's of
different makes, contain a multitude of trace element impurities at various concentration levels including also amounts which
can be considered as nanoelectronically dopant quantities. The same holds for the above mentioned carbon nanotubes also after
their inadequately so-called purification.
Authors:A. Béres, I. Pálinkó, Á. Fudala, I. Kiricsi, Y. Kiyozumi, F. Mizukami, and J. Nagy
Mg-Al L(ayered) D(ouble) H(ydroxide) was prepared and its thermal behaviour was characterized by thermoanalytical methods
(TG, DTG, DTA), 27Al M(agic) A(ngle) S(pinning) NMR spectroscopy, X-ray diffractometry (XRD) and S(canning) E(lectron) M(icroscopy). Heat treatment
destroyed the layered structure, which could only be partially reconstituted by rehydration. On calcination mixed oxide with
the predominance of basic sites were formed. Pillaring the LDH with Fe(CN)64- anions was also performed. The material was characterized by XRD and BET measurements. Heat stability of the pillared substance
was investigated, too. Pillaring proved to be successful, however, decreased heat resistance was found in the intercalated
material relative to the guest LDH.
Authors:A. Szabo, A. Fonseca, L. P. Biro, Z. Konya, I. Kiricsi, A. Volodin, C. Van Hasendonck, and J. B.Nagy
Some recent results on
the synthesis of coiled carbon nanotubes (CNTs) are summarized. Several
supported catalysts can lead to the formation of coiled CNTs. Interestingly,
certain domains of the coil pitch and coil diameter are favoured, and two
“stability islands”are found in the 3D representation of the number of coiled
CNTs as a function of both coil pitch and coil diameter. It is emphasized that
these nanotubes are formed either by introducing pairs of five-membered ring -
seven-membered ring or by forming haeckelite structures. The coiled CNTs could
be used in nanocomposite reinforcement as well as special sensors based on
their remarkable mechanical and electrical properties.