Electronic structure of Eu atomic wires encapsulated inside single-wall carbon nanotubes

Abstract

X-ray absorption (resonant) photoelectron spectroscopy has been employed to investigate electronic structure of Eu atomic wires encapsulated in single-wall carbon nanotubes (SWCNTs). The measurements reveal that there is a substantial electron transfer of + 1.79 ± 0.11 from a Eu atom to the surrounding SWCNT. The shape of the observed Fermi edge is different from that of a three-dimensional metal, suggesting that electrons in this one-dimensional system form a Tomonaga-Luttinger liquid.

Advances in tailoring the electronic properties of single-walled carbon nanotubes

“…Figure 32с shows the part of the C 1s XAS spectra containing the *-resonance of the nanotubes filled with cerocene in comparison with the data of the pristine SWCNTs [269]. The same changes in the C 1s XAS spectra were reported for SWCNTs filled with Eu [272] and ferrocene [50,262,263]. KGaA, Weinheim [269].…”

“…Among them are ferrocene [50,262,263,267], cerocene [51,269] and europium [272] (Table 3). Figure 32b demonstrates the spectrum of the SWCNTs filled with cerocene in comparison with the spectrum of pristine nanotubes [269].…”

“…It is worth noticing that it was reported that metallic silver inside the SWCNTs can also be obtained by the photolytic decomposition of the encapsulated silver chloride [21]. To introduce the europium into the SWCNT channels, the gas phase approach was used [272]. Figure 30 shows the HRTEM micrographs of the SWCNTs filled with electron donors.…”

“…According to the data presented in reports on the experimental and theoretical investigations of the electronic properties of filled SWCNTs, the following substances have an electron donor effect on the nanotubes: molecules -organic molecules (tetrakis(dimethylamino)ethylene (TDAE) and tetrathiafulvalene (TTF) [48,356]) and organometallic molecules (Co(C 5 H 5 ) 2 , Co(C 5 H 4 C 2 H 5 ) 2 [47,399,400], Fe(C 5 H 5 ) 2 [50,260,262,263,265,267,399,400], Ce(C 5 H 5 ) 3 [51,269], M(C 5 H 5 ) 2 , M= V, Cr, Mn, Ni [399]) and simple substances -metals (Ag [46,293,294,296,315,365,401], Cu [293,295], Eu [272,402], Li, K [403], Ti, Zn, Co, Ni, Fe, Mo, Gd, Cu [402,[404][405][406][407][408][409][410]). …”

“…Using this method the SWCNT cavities were filled with С 60 , C 70 Furthermore, using this method the SWCNTs were filled with simple substances (nonmetals -Se [17] and metals -K [273], Bi [20], Eu [271,272]), halogenides (ZrCl 4 [23,24]) and oxides (Re x O y [18]) ( Table 1). Figure 18 shows the HRTEM data of the SWCNTs filled using the gas phase method.…”