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.

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The two‐dimensional (2D) metal‐organic frameworks (MOFs) have capabilities to reduce CO2 with high Faradaic efficiency (FE). Herein, the role of incorporating bimetallic Ni and Fe into newly constructed MOFs is studied. This work highlights the use of bimetallic synergistic effect with surrounded nitrogen atoms, opening new avenues for efficient electrocatalytic reduction of CO2. This MOF Ni‐Fe contains moieties surrounded by four nitrogen atoms via covalent bonding, which resembles the porphyrin‐based molecular units as selective and effective homogeneous CO2 reduction electrocatalysts. Besides, density functional theory (DFT) also helps to figure out that the incorporation combination of metals helps achieve the high FE of 98.2% with stability up to 30 h under a low applied potential of −0.5 V versus reversible hydrogen electrode (RHE). These results offer a promising avenue to develop and optimize the MOFs‐based electrocatalysts for electrochemical conversion of CO2.

Graphene nanocomposites can significantly enhance the thermal conductivity and mechanical properties of ceramics at relatively low nano-filler addition.

Synthesis of silicon/carbon (Si/C) composites from biomass resources could enable the effective utilization of agricultural products in the battery industry with economical as well as environmental benefits. Herein, a simplified process was developed to synthesize Si/C from biomass, by using a low‐cost agricultural byproduct “rice husk (RH)” as a model. This process includes the calcination of RH for SiO2/C and the reduction of SiO2/C by Al in molten salts at a moderate temperature. This process does not need the removal of carbon before thermal reduction of SiO2, which is thought to be necessary to avoid the formation of SiC at elevated temperatures. Thus, carbon derived from biomass can be directly used for Si/C composites for anode materials. The resultant Si/C shows a high reversible capacity of 1309 mAh g−1 and long cycle life (300 cycles). This research advocates a new and simplified strategy for the synthesis of RH‐based biomass‐derived Si/C, which is beneficial for low‐cost, environmentally friendly, and green energy storage applications.

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Transition metal oxides (TMO) have great potential applications in efficient energy storage devices for their commercial possibilities in lithium-ion batteries (LIBs).