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Lithium‐sulfur batteries (LSBs) with high theoretical specific capacities have been regarded as the development direction of next generation energy storage. However, the shuttle effect of lithium polysulfides (LiPSs) and the retardation of conversion kinetics have hindered their industrial application. Herein, Mn selectively doped CoP hollow microspheres are designed and synthesized to trap LiPSs and enhance Li–S reaction kinetics. Mn is successfully doped into (100) surfaces of Co3O4 via simple hydrothermal reaction, whereas it is only excessively accumulated on (111) surfaces. The unique selective doping of Mn not only provides an accurate and controllable synthesis path, but also makes synthesized target products rich in phosphorus defects after thermal shock. The adsorption, electrochemical, and in situ XRD and Raman tests prove its enhancement in adsorption capacity for LiPSs and inhibition of shuttle effect. Meanwhile, density functional theory calculations confirm that the reduced reaction energy barriers accelerate the reduction kinetics of sulfur redox conversion. Therefore, the optimal electrode displays an outstanding cycling stability with a capacity fading rate of just 0.0207% per cycle over 1000 cycles at 1 C. This study provides a novel design to promote the practical use of LSBs by introducing lattice defects, enlightening further developments of LSBs. [ABSTRACT FROM AUTHOR]

Given their high energy/power densities and long cycle time, lithium‐ion batteries (LIBs) have become one type of the most practical power sources for electric/hybrid electric automobile, portable electronics, and power plants. However, the performance attenuation of LIBs has limited their applications in many energy‐related systems. In this review, the performance attenuation mechanisms of LIBs and the effort in development of mitigation strategies are comprehensively reviewed in terms of the commonly used cathode materials and anode materials, electrolytes, and current collectors. Several challenges are analyzed and several further research directions are also proposed for overcoming the challenges toward improvement of LIB performance. [ABSTRACT FROM AUTHOR]

Electro‐oxidative organic upgrading, as an ideal alternative to sluggish oxygen evolution reaction (OER) performance, can effectively decrease energy consumption to boost hydrogen evolution reaction (HER) performance. However, developing highly active electrocatalysts for long‐term durable organic upgrading with high selectivity at large and steady current density remains challenging. Herein, hollow NiSe nanocrystals heterogenized with carbon nanotubes (h‐NiSe/CNTs) are fabricated via a facile one‐pot approach. The highly dispersed h‐NiSe/CNTs 3D network can efficiently facilitate rapid mass/electron diffusion, thus achieving highly active and long‐term stable electrocatalysis for catalyzing methanol to value‐added formate at high and steady current density (≈345 mA cm−2) with high Faradaic efficiency (>95%). This reaction replaces sluggish OER performance to reduce the energy consumption for boosting H2 generation by six times. The critical active species and methanol activation mechanism are systematically studied using X‐ray photoelectron spectroscopy, X‐ray absorption fine structure analysis, in situ Raman, and density functional theory calculations, indicating that the non‐ignorable SeOx collaborated with in situ formed NiOOH species can synergistically modulate the d band center to achieve an optimal adsorption for methanol selective oxidation and suppress the further oxidation to CO2, thus leading to active and stable electrolysis for producing value‐added formate with high selectivity and co‐generating H2 with less energy consumption. [ABSTRACT FROM AUTHOR]

Deciphering the relationship between electron configuration and catalytic activity is crucial for designing electrocatalysts that improve the efficient conversion of lithium polysulfides (LiPSs). In this study, amorphous ZnAl2O4 (referred to as A‐ZnAl2O4) is designed with a high oxygen vacancy concentration. Experimental and theoretical analysis confirm that the Zn tetrahedral sites are sufficiently exposed, and the catalytic activity is significantly enhanced due to a narrow bandgap and a high spin state achieved through low coordination numbers and a disordered structure. Both the enhancement in electron transfer efficiency and reduction in reaction energy barriers accelerate the multi‐phase transformation of LiPSs, resulting in impressive electrochemical performance with a capacity retention rate of 93.9% after 800 cycles at a high current density of 4 C. And the pouch battery with high sulfur loading of 4.5 mg cm−2 and lean electrolyte at 8 µL mg−1 exhibits high discharge capacity and stable cycling. This research deciphers the amorphization on modulating electronic structures to achieve enhanced electrocatalytic activity, providing a general strategy for designing unique atomic‐scale band structures and spin states in multifunctional electrocatalysts. [ABSTRACT FROM AUTHOR]

Sr2Fe1.5Mo0.5O6‐δ (SFM) perovskite oxide is one of the most promising materials for solid oxide fuel cells (SOFCs) anode. However, the low catalytic activity is a major roadblock that obstructs its practical applications. Although in situ exsolution of B‐site metals is demonstrated as a promising approach to enhancing its performance, it can easily induce the co‐segregation of A‐site Sr, which seriously deteriorates the performance stability. In this work, the A‐site Sr element in SFM is partially replaced by Pr, while B‐site Mo is partially replaced by Ni. The in situ co‐exsolution of both FeNi alloy and PrOx nanoparticles on the reduced Pr0.8Sr1.2Fe1.5Mo0.3Ni0.2O6‐δ (R‐PSFMN) perovskite is successfully achieved. It is found that the peak power densities (Pmax) of the single cell using R‐PSFMN as the anode reaches as high as 2.29, 1.60, 1.07, and 0.67 W cm−2 in H2 atmosphere at the operating temperatures of 850, 800, 750 and 700 °C, respectively. Furthermore, it also exhibits excellent performance stability and anticoke properties when using ethane as fuel. The impregnation experiment further corroborates that the improved performance and stability are partly attributable to the contribution of PrOx nanoparticles, presenting a promising approach to enhance the electrochemical performance of SOFC perovskite anodes. [ABSTRACT FROM AUTHOR]