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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]

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]

Rational design of sulfur hosts for effectively confining lithium polysulfides (LiPS) and optimizing the sluggish sulfur kinetics is still a major challenge in lithium–sulfur batteries (LSBs). In this work, a simple strategy of introducing single Mo–N4 atoms into N‐doped carbon nano‐flower matrix (Mo‐N‐CNF) as sulfur host cathode materials is developed to realize high‐performance LSBs. These single Mo–N4 atoms have been demonstrated to regulate the hydrophilic nature, Li‐ion diffusion, adsorption capacity, and catalytic conversion of polysulfides via experimental evidences and theoretical calculations. The resulting Mo‐N‐CNF with high loading content of sulfur (>72 wt.%) exhibits a high specific capacity (1248 mAh g–1 at 0.2 C) and excellent rate capability (715 mAh g–1 at 5 C). More importantly, the outstanding cycling performance with a low attenuation rate of only 0.004% per cycle over 400 cycles at 4.27 mA cm–2 is achieved with the area sulfur loading of 5.1 mg cm–2. This work demonstrates a viable strategy for using single atoms‐based carbon materials with high exposed sites as multiple captors for LiPS and an efficient accelerator for sulfur redox kinetics toward next‐generation LSBs with boosted electrochemical performance. [ABSTRACT FROM AUTHOR]

As an all-inorganic zero-dimensional (0D) lead-free metal halide, Cs2ZnCl4 is a potentially excellent matrix for preparing chemically stable and environmentally friendly photoluminescent materials through an ion-doping strategy. Therefore, it is necessary to study the emission properties of every kind of doping ion in the tetrahedral coordination of Cs2ZnCl4. Here, for the first time, we successfully synthesized Te4+-doped Cs2ZnCl4 single crystals via a facile hydrothermal method. X-ray crystallography clearly reveals the strong distortion of the tetrahedral units in Cs2ZnCl4 caused by doping with Te4+. Broadband yellow-light emission covering the range from 450 nm to 700 nm with a large Stokes shift is observed in Cs2ZnCl4:Te4+ single crystals, and this is attributed to self-trapped excitons (STEs) caused by the lattice vibration of the distorted structure. It is worth mentioning that this broadband yellow phosphor can be excited by a wide range of blue light, implicitly giving it an excellent ability to adapt to multiple models of blue LED chips, thus serving as a suitable yellow phosphor that can be applied to fabricate WLEDs without the need to worry about the lack of red light. [ABSTRACT FROM AUTHOR]

An efficient and durable oxygen evolution reaction (OER) electrocatalyst consisting of TiN @ Co5.47N is constructed by the integration of plasma nitriding and a delicate atomic layer deposition (ALD) CoxN process. Representative results of comprehensive study are: 1) the material is electrocatalytically active in universal medium. The OER overpotentials are 398, 248, and 411 mV in acidic, basic, and neutral electrolyte, respectively, at a current density of 50 mA cm−2; 2) the material records an impressive long‐term stability of continuous catalysis for 1500 h, during which the overpotential increases by only 1.3%. The synergistically electronic interaction between TiN and ALD Co5.47N, as well as a protective yet active CoTi layered double hydroxides (CoTi LDH) layer formed simultaneously at the interface/surface of TiN @ Co5.47N during the electrocatalytic process, is speculated to be responsible for the superior OER performance; 3) the surface Co atoms other than Ti of CoTi LDH, exhibit electrocatalytic activity with dramatically low overpotential based on density functional theory calculations. [ABSTRACT FROM AUTHOR]

Reported herein is the investigation of a unique cathode candidate for Li–S batteries, i.e. Ni3S2/(N, S)-RGO-type hybrid materials, which are expected to optimize battery performance by elevating the utilization of sulfur and chemically confining the adsorption/diffusion of polysulfide. Versatile structural and compositional characterizations confirmed the uniform growth and strong chemical coupling of nanostructured Ni3S2 on the N/S co-doped RGO matrix. Rich physical and chemical properties were revealed, namely, the large specific surface area and pore volume, which are beneficial for polysulfide capture, and the 3D conductive network supporting rapid charge transfer to the Ni3S2-polysulfide interface to improve the intrinsic equilibrium of the polysulfide. Specifically, the integration of ∼28.2 wt% of Ni3S2 produced a highly pleated composite with the largest BET specific surface area (618 m2 g−1) and pore volume (1.73 cm3 g−1) among the hybrids studied. This typical material also performed the best in the battery test, recording ultra-high cycling stability over 1000 cycles at the current density of 3C with the capacity decay of 0.023% per cycle. As the sulfur loading per unit area became as dense as 5.8 mg cm−2, the specific capacities were measured as 6.72 mA h cm−2 (at 0.05C), while the capacity retention for the 200-cycle test (at 1C) was still preserved above 72.5%. [ABSTRACT FROM AUTHOR]