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First Principles Investigations on Structural, Elastic, Electronic, and Optical Properties of Li₂CdGeS₄

“…It is due to their promising, tunable properties in varying the chemical composition, and thereby optimizing the material functionality. They may bring out more applications in the areas of photovoltaics, 1) nonlinear optics, 2,3) thermoelectrics, 4) solar cells and light-emitting diodes. 5) The researches on the quaternary I 2 IIIVVI 4 compounds 610) have been reported, especially Cu 2 ZnGeS 4 has drawn much attention as being a promising candidate as absorber layer in solar cell technologies.…”

“…Additionally, the presence of Li as the univalent cation allows for the use of a lithium polysulfide flux as a reaction medium to promote crystal growth. Li et al 12) investigated the electronic structure and lattice dynamic properties of Li 2 CdGeS 4 . We all know that the systematical information on the structural, elastic, electronic, optical and bonding properties of I 2 IIIVVI 4 compounds are helpful to further understand the physical properties of semiconductors.…”

ELECTRICAL BEHAVIOR OF A Cu2Fe0.4Co0.6SnS4 CERAMIC

“…For its part, Cu 2 CoSnS 4 , which was transformed into a ceramic with a 97% densification, was measured with the impedance complex, which showed that it had the electrical behaviour of a semiconductor with a conductivity of 30 S/cm at 250 K. This conductivity is greater than that of the crystalline powder of Cu 2 MnSnS 4 (0.10 S/cm at 296 K) [1]. In the plot of the electrical conductivity as a function of the inverse of the temperature (Figure 8), three changes in the slope were observed, which can be interpreted as; a zone in which the conductivity is dominated by free charge carriers (high temperature) and in another dominating hopping type mechanism [12].…”

“…The Cu 2 FeSnS 4 phase was measured in a pellet without sintering using the Van der Pauw method. This phase presented the behavior of a semiconductor with a conductivity of 0.071 S/cm at 250 K, which is a greater conductivity value than in single crystals of Cu 2 CdGeS 4 (0.003 S/cm at 250 K) [12]. For its part, Cu 2 CoSnS 4 , which was transformed into a ceramic with a 97% densification, was measured with the impedance complex, which showed that it had the electrical behaviour of a semiconductor with a conductivity of 30 S/cm at 250 K. This conductivity is greater than that of the crystalline powder of Cu 2 MnSnS 4 (0.10 S/cm at 296 K) [1].…”

“…The activation energy was found to be 0.03 eV at room temperature [1]. In a subsequent study using this same technique, it was determined that Cu 2 CdGeS 4 also has an Ea = 0.03 eV [12]. In addition, using theoretical calculations it was estimated that the band gaps (E g ) were approximately 1.5 eV in Cu 2 ZnSnS 4 and 1.0 eV in Cu 2 ZnSnSe 4 [2,13].…”