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Conductive metal‐organic frameworks (MOFs) are promising electrode materials for supercapacitors (SCs) because of their tunable structures, high specific surface areas, and superior conductivity. However, it remains challenging to develop conductive MOFs for organic SCs and the role of metal ions in the electrochemical performance of MOFs is still unclear but is shown to be a key factor in determining MOFs performance. Herein, two high‐performance ultra‐thin redox conductive 2D MOFs (>6000 S m−1) for SCs are prepared, and the effects of metal ions on the capacitive performance of MOF electrodes are investigated. Co2+ and Mn2+ with the same ligand provide two MOFs featuring almost the same structures and specific surface areas but show great differences in electrochemical performance except that both MOFs exhibit outstanding electrochemical performance and good cycling stability with a capacity retention of >85% after 10 000 cycles. Different metal ions endow the two MOFs with different redox behaviors, conductivities, and energy levels, where Co‐MOF shows superior specific capacity compared to Mn‐MOF. This work expands the possibility of the use of MOFs in SCs and gives insight into the roles of metal ions in MOFs.

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Achieving fast ionic conductivity in the electrolyte at low operating temperatures while maintaining the stable and high electrochemical performance of solid oxide fuel cells (SOFCs) is challenging. Herein, we propose a new type of electrolyte based on perovskite Sr0.5Pr0.5Fe0.4Ti0.6O3−δ for low-temperature SOFCs. The ionic conducting behavior of the electrolyte is modulated using Mg doping, and three different Sr0.5Pr0.5Fe0.4–x Mg x Ti0.6O3−δ (x = 0, 0.1, and 0.2) samples are prepared. The synthesized Sr0.5Pr0.5Fe0.2Mg0.2Ti0.6O3−δ (SPFMg0.2T) proved to be an optimal electrolyte material, exhibiting a high ionic conductivity of 0.133 S cm–1 along with an attractive fuel cell performance of 0.83 W cm–2 at 520 °C. We proved that a proper amount of Mg doping (20%) contributes to the creation of an adequate number of oxygen vacancies, which facilitates the fast transport of the oxide ions. Considering its rapid oxide ion transport, the prepared SPFMg0.2T presented heterostructure characteristics in the form of an insulating core and superionic conduction via surface layers. In addition, the effect of Mg doping is intensively investigated to tune the band structure for the transport of charged species. Meanwhile, the concept of energy band alignment is employed to interpret the working principle of the proposed electrolyte. Moreover, the density functional theory is utilized to determine the perovskite structures of SrTiO3−δ and Sr0.5Pr0.5Fe0.4–x Mg x Ti0.6O3−δ (x = 0, 0.1, and 0.2) and their electronic states. Further, the SPFMg0.2T with 20% Mg doping exhibited low dissociation energy, which ensures the fast and high ionic conduction in the electrolyte. Inclusively, Sr0.5Pr0.5Fe0.4Ti0.6O3−δ is a promising electrolyte for SOFCs, and its performance can be efficiently boosted via Mg doping to modulate the energy band structure.

The syntheses of 5-pyridyl-3(beta-D-galactopyranosyl)-1,3,4-oxadiazole-2-thiones 3a-3c and 5-pyridyl-2(beta-D-galactopyranosyl)-4-benzyl-1,2, 4-triazole-3-thiones 6a-6c are reported. The existence of N-galactosides--not S-galactosides--was proven by IR and 15N NMR spectroscopy. The structures of the final products and the intermediates were elucidated by IR, 1H, 13C and 15N NMR spectroscopy and mass spectrometry.