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Herein, amorphous molybdenum oxide films are constructed by thermal atomic layer deposition (T‐ALD) and plasma‐enhanced atomic layer deposition (PE‐ALD). The physical and chemical properties of molybdenum oxide films prepared by the two methods are systematically compared by means of film growth law, atomic force microscope, scanning electron microscope, etc. The results show that the amorphous molybdenum oxide physical phase prepared by both ALD methods is MoO3. Compared with T‐ALD MoO3, the growth rate of MoO3 thin films prepared by PE‐ALD is higher. Compared to PE‐ALD MoO3, the MoO3 films prepared by T‐ALD did not have nucleation delayed to a laminar growth mode, resulting in smoother deposited films and contained less impurity carbon. The MoO3 prepared by PE‐ALD contains 7.4% impurity carbon. This carbon‐doped film significantly improves the conductivity of the MoO3 film and shows good electrochemical activity. As expected, the MoO3 films prepared by PE‐ALD show good electrocatalytic oxygen evolution reaction. The overpotential is only 259 mV at 10 mA cm−2 and continues to evolution oxygen for 60 h with almost no attenuation, indicating that carbon doping significantly improves the catalytic intrinsic activity and stability of MoO3. [ABSTRACT FROM AUTHOR]

Nitrogen and phosphorus co‐doped porous carbon plate (NPCP) was prepared by simple pyrolysis carbonization and alkali activation of biomass duckweed NPCP displays the largest specific surface area (SSA) of 2023 m2 g−1, and is rich in pyridine N and P doping, which makes the metal‐free carbon have excellent electrocatalytic oxygen reduction performance. The best NPCP2 shows a half‐wave potential of 0.19 V vs. Ag/AgCl in alkaline electrolyte, and its activity is equivalent to that of commercial platinum carbon (Pt/C). In addition, it shows excellent methanol toxicity resistance and continuous catalytic stability. The experimental results show that the heteroatom doping method obtained by biomass hydroponics has great advantages and great application value in the catalytic field of porous carbon materials. [ABSTRACT FROM AUTHOR]

The construction of lithium–sulfur battery cathode materials while simultaneously achieving high areal sulfur‐loading, adequate sulfur utilization, efficient polysulfides inhibition, rapid ion diffusion, etc. remains a major challenge. Herein, an internal regulatory strategy to fabricate the unique walnut‐like yolk–shell carbon flower@carbon nanospheres is presented (WSYCS) as sulfur hosts. The internal carbon flower, suitable cavity, and external carbon layer effectively disperse the insulate sulfur, accommodate volumetric expansion, and confine polysulfides, thus improving the performance of lithium–sulfur batteries. The finite element simulation method also deduces the enhanced Li+ diffusion and lithium–sulfur reaction kinetics. More importantly, WSYCS2 is grafted onto carbon fiber (CF) by electro‐spinning method to form a tandem WSYCS2@CF 3D film as a sulfur host for the free‐standing electrode. The corresponding battery exhibits an extremely high areal capacity of 15.5 mAh cm−2 with a sulfur loading of 13.4 mg cm−2. Particularly, the flexible lithium–sulfur pouch cell delivers a high capacity of 8.1 mAh cm−2 and excellent capacity retention of 65% over 800 cycles at a relatively high rate of 1C, corresponding to a calculated energy density of 539 Wh kg−1 and 591 Wh L−1. This work not only provides guidance for tailoring thick carbon/sulfur electrodes but also boosts the development of practical lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

Sustainability and adaptability in structural design of the organic cathodes present promises for applications in alkali metal ion batteries. Nevertheless, a formidable challenge lies in their high solubility in organic electrolytes, particularly for small molecular materials, impeding cycling stability and high capacity. This study focuses on the design and synthesis of organic small molecules, the isomers of (E)‐5,5′‐difluoro‐[3,3′‐biindolinylidene]‐2,2′‐dione (EFID) and 3,9‐difluoro‐6,12‐dihydrodibenzo [c, h][2,6]naphthyridine‐5,11‐dione (FBND). While EFID, characterized by a less π‐conjugated structure, exhibits subpar cycling stability in lithium‐ion batteries (LIBs), intriguingly, another isomer, FBND, demonstrates exceptional capacity and cycling stability in LIBs. FBND delivers a remarkable capacity of 175 mAh g−1 at a current density of 0.05 A g−1 and maintains excellent cycling stability over 2000 cycles, retaining 90% of its initial capacity. Furthermore, an in‐depth examination of redox reactions and storage mechanisms of FBND are conducted. The potential of FBND is also explored as an anode in lithium‐ion batteries (LIBs) and as a cathode in sodium‐ion batteries (SIBs). The FBND framework, featuring extended π‐conjugated molecules with an imide structure compared to EFID, proves to be an excellent material template to develop advanced organic small molecular cathode materials for sustainable batteries. [ABSTRACT FROM AUTHOR]

Lithium/sodium‐based batteries have attracted widespread attention because of their high specific capacity and excellent energy density, and have become one of the hottest research directions in energy storage devices. However, the stress accumulated during the continuous electrochemical cycle will cause the inevitable electrode failure, which inhibits the further improvement of battery performance. In order to eliminate/relieve the internal stress problem, a variety of battery material structures have been designed. In the design of battery material structure, the simulation technology is used to conduct battery modeling to predict the experimental results, which effectively reduces the range of parameters. For this reason, this paper first introduces the parameters that need to be considered by establishing stress model. Then, the utilization of simulation technology in the structural design of diverse battery materials is examined in this study. Finally, the future application of simulation technology in the field of energy storage is prospected. This is aimed to encourage the widespread utilization of simulation technology in the energy storage battery industry, with the goal of reducing design‐related energy consumption, enhancing experimental design feasibility, and minimizing experimentation costs. [ABSTRACT FROM AUTHOR]

Herein, we investigated in detail the effect of metal valences in different cobalt‐based organic framework compounds on the kinetics of sulfur reaction in lithium‐sulfur batteries (LSBs). On this basis, two organic framework compounds of zeolite‐imidazole‐based cobalt organic framework compound (Co‐ZIF) and tetrakis(4‐benzoic acid) porphyrinato‐CoIII chloride [Co‐TBP(III)] with different valences were constructed as the functional intercalation separators of LSBs, and explored the effects of different valences on improving the reaction kinetics of polysulfides and inhibiting the shuttle effect. Experiments and theoretical calculations prove that CoII exhibits the best catalytic activity. This is mainly due to the fact that +2 valence shows a strong adsorption energy for polysulfides and a higher Fermi level compared with +3 valence, thus improving the efficiency of the rapid catalytic conversion of sulfur species. As expected, the discharge specific capacity of Co‐ZIF as the catalytic layer of the LSBs reached 772.7 mAh g−1 at a high current density of 5 C. More importantly, the initial specific capacity is 839.6 mAh g−1 at high current 3 C, and after 720 cycles, the attenuation rate of per cycle is only 0.092 %, and the coulombic efficiency remains above 92 %. [ABSTRACT FROM AUTHOR]