Spontaneous Non-stoichiometry and Ordering in Degenerate but Gapped Transparent Conductors

Chemistry of Oxygen Ionosorption on SnO2 Surfaces

“…Similar energy shifts for chemical potentials are commonly implemented when calculating the formation energies of oxides 73 − 75 and defects therein. 70 , 76 However, this simple approximation does not account for a different degree of overbinding in O 2 – species, which may lead to a partisan stabilization of atomic O over molecular O 2 ionosorption. Finding a configuration-dependent correction may require a detailed comparative analysis of different species with various functionals, which is beyond the scope of this study.…”

Gapped metals as thermoelectric materials revealed by high-throughput screening

“…We note that there is precedent for probing these gapped metals for functional applications other than thermoelectrics. The presence of a gap close to the Fermi level in metallic systems and its influence on the electronic and optical properties has been already discussed mainly in the field of transparent conductive oxides [24,[44][45][46][47] and recently for applications in low-loss plasmonics [48]. Therefore, given that this key feature of the band structure can potentially be exploited for other applications, we report all the gapped metals found by this screening along with their calculated properties (in SI).…”

“…Ab initio band structure calculations show that, while these materials are indeed metals with some bands crossed by the Fermi level, there is an energy band gap below or above the latter. Adopting the nomenclature of Malyi et al [24], we refer to a gap below (resp. above) the Fermi level as an internal (resp.…”

Defects Engineering with Multiple Dimensions in Thermoelectric Materials

“…Recently, Zunger's group has predicted that in some degenerate but gapped transparent conductors such as the Ba-Nb-O system, vacancies can be arranged in an ordered way, of which the possibility is enabled by the negative formation energies of dilute vacancies originated from the Fermi level-induced spontaneous nonstoichiometry. It is also predicted that there is a sequence of possible stable arrangement of ordered vacancies, and they exhibit different free carrier concentration and optoelectronic properties [98]. But, up to now, there are few researches studying the possible ordered arrangement of defects in thermoelectric materials and linking it with thermoelectric transport behavior.…”