Lithium ions in the van der Waals gap of Bi{sub 2}Se{sub 3} single crystals

• Published in: Journal of solid state chemistry 2010-12, Vol.183 (12)
• Main Authors: Bludska, J., Jakubec, I., Karamazov, S., Horak, J., Uher, C.
• Format: Article
• Language: English
• Subjects: BISMUTH COMPOUNDS; BISMUTH SELENIDES; CHALCOGENIDES; CHARGED PARTICLES; CRYSTALS; EXTRACTION; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; IONS; LAYERS; LITHIUM IONS; MONOCRYSTALS; SELENIDES; SELENIUM COMPOUNDS; SEPARATION PROCESSES; VAN DER WAALS FORCES; VOLTAMETRY
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2010.09.026

Insertion/extraction of lithium ions into/from Bi{sub 2}Se{sub 3} crystals was investigated by means of cyclic voltammetry. The process of insertion is reflected in the appearance of two bands on voltammograms at {approx}1.7 and {approx}1.5 V, corresponding to the insertion of Li{sup +} ions into octahedral and tetrahedral sites of the van der Waals gap of these layered crystals. The process of extraction of Li{sup +} ions from the gap results in the appearance of four bands on the voltammograms. The bands 1 and 2 at {approx}2.1 and {approx}2.3 V correspond to the extraction of a part of Li{sup +} guest ions from the octahedral and tetrahedrals sites and this extraction has a character of a reversible intercalation/deintercalation process. A part of Li{sup +} ions is bound firmly in the crystal due to the formation of negatively charged clusters of the (LiBiSe{sub 2}.Bi{sub 3}Se{sub 4}{sup -}) type. A further extraction of Li{sup +} ions from the van der Waals gap is associated with the presence of bands 3 and 4 placed at {approx}2.5 and {approx}2.7 V on the voltammograms as their extraction needs higher voltage due to the influence of negative charges localized on these clusters. -- Graphical abstract: Insertion/extraction of lithium ions into/from Bi{sub 2}Se{sub 3} layered crystals was investigated by cyclic voltammetry. The extraction of Li{sup +} results in the appearance of four bands on the voltammograms. The first two bands have a character of a reversible process. A part of Li{sup +} ions is bound firmly in the crystal due to the formation of negatively charged clusters of the (LiBiSe{sub 2}.Bi{sub 3}Se{sub 4}{sup -}) type. Their extraction needs higher voltage due to the negative charge. Display Omitted