Neri, F. (1994) Proprietà elettroniche del tiofosfato di nickel intercalato con litio. Accademia Peloritana dei Pericolanti Classe FF.MM.NN., LXXII (Supplement 1). pp. 139-153.
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Electrical transport and Xray photoelectron spectroscopy measurements were made on lithium-intercalation complexes $Li_xNiPS_3$ Conductivity measurements werc made both during the intercalation process and after the intercalation was ceased. The intercalation process was characterized by means of the conductivity measurements ar a function of the intercalation time. Results for equilibrated samples are presented as a function of both the temperature and the lithium concentration. An overali and quick increase in the electrical conductivity, a contemporaneous decrease in the activation energy and a degenerate semiconducting behaviour at high lithium contents were observed, All these effects suggested that, with respect to the pure $NiPS_3$, a new conduction mechanism occurs at a different energy level since the very beginning of the intercalation process. In the early intercalation times a simple empirical model was formulated to correlate the data as a function of the intercalation time and those as a function of temperature. A detailed $XPS$ study was performed at the $2p$ core levels of the nickel atoms for various lithium contents. Comparison of the $Ni 2p$ peak structure, corresponding to $NiPS_3$ and $Li_xNiPS_3$ systems, shows some evident trends, In particular, a shift of the Ni main line towards lower hinding energies and a decrease in the intensity of the $Ni 2p$ satellite structures with lithium content are observed. All these findings suggest a change in the $3d$ electron configuration for high lithium concentrations. Taking the probable nickel reduction into account, a possible identification of the lithium 2s electron accepting levels was proposed.
|Subjects:||M.U.S. - Miscellanea > Atti Accademia Peloritana > Classe di Scienze Fisiche, Matematiche e Naturali > 1994 > Supplemento 1 parte 1
M.U.S. - Miscellanea > Atti Accademia Peloritana > Classe di Scienze Medico-Biologiche > 1994 > Supplemento 1 parte 1
M.U.S. - Miscellanea > Atti Accademia Peloritana > Classe di Scienze Giuridiche, Economiche e Politiche > 1994 > Supplemento 1 parte 1
M.U.S. - Miscellanea > Atti Accademia Peloritana > Classe di Lettere, Filosofia e belle Arti > 1994 > Supplemento 1 parte 1
|Depositing User:||Mr Nunzio Femminò|
|Date Deposited:||01 Apr 2014 11:51|
|Last Modified:||01 Apr 2014 11:51|
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