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The electrical properties (permittivity, dissipation factor, and electrical conductivity) of the Li0.03Na0.97TayNb1 – yO3 (y = 0.1–0.7) ferroelectric solid solutions with a perovskite structure have been studied. In the temperature range of 290–830 K, the investigated solid solutions undergo three phase transitions. The phase transitions are strongly smeared with increasing tantalum concentration. The Curie temperatures have been established, and it has been shown that an increase in the tantalum concentration leads to a decrease in the Curie temperature. The static electrical conductivity of the Li0.03Na0.97TayNb1 –yO3 (y = 0.1–0.7) ferroelectric solid solutions and the activation enthalpies of charge carriers have been determined. [ABSTRACT FROM AUTHOR]

Density functional theory calculations are employed to investigate the effects of various metal dopants on thiolates-protected transition metal nanoclusters (NCs) for CO 2 reduction, focusing on deviations from the linear scaling relation between COOH* and CO* for high CO selectivity. We first explore the most favorable positions for different dopants in several M 25 (M=parent metal) NCs and assess the potential for ligand removal under reducing conditions. Furthermore, we construct an activity volcano for CO production in D 1 M 24  (D=dopant) NCs, revealing that NCs composed of coinage parent metals with group 12 metal dopants exhibit the most significant deviation from the scaling relation. This behavior is attributed to the tendency of these NCs to bind COOH* in a bidentate form, which stabilizes the O atom of COOH* through interactions with the oxyphilic dopants. As a result, several group 12 metal doped coinage metal NCs are identified as new promising candidates for syngas production due to their high activity towards both CO and H 2 production., (© 2024 Wiley-VCH GmbH.)

Electrocatalytic CO 2 reduction reaction (CO 2 RR) is greatly facilitated by Au surfaces. However, large fractions of underlying Au atoms are generally unused during the catalytic reaction, which limits mass activity. Herein, we report a strategy for preparing efficient electrocatalysts with high mass activities by the atomic-level transplantation of Au active sites into a Ni 4 nanocluster (NC). While the Ni 4 NC exclusively produces H 2 , the Au-transplanted NC selectively produces CO over H 2 . The origin of the contrasting selectivity observed for this NC is investigated by combining operando and theoretical studies, which reveal that while the Ni sites are almost completely blocked by the CO intermediate in both NCs, the Au sites act as active sites for CO 2 -to-CO electroreduction. The Au-transplanted NC exhibits a remarkable turnover frequency and mass activity for CO production (206 mol CO /mol NC /s and 25,228 A/g Au , respectively, at an overpotential of 0.32 V) and high durability toward the CO 2 RR over 25 h.