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• FeS nanoparticles embedded in N -doped porous C is prepared by one-step strategy. • The N -doped C can improve conductivity, introduce defects and more active sites. • The FeS/NC electrode displays superior lithium-ion storage performance. • The electrochemical reaction mechanism is studied by ex-situ XPS. The electrode materials with simple preparation methods, good electrochemical performance, and cheap cost have broad application prospects in the field of electrochemistry. Herein, we propose one-step method for the direct sulfuration of iron-phthalocyanine (FePc) to produce FeS nanoparticles embedded in nitrogen-doped porous carbon (FeS/NC). Introducing porous carbon materials into the FeS nanoparticles can significantly restrain the huge volume expansion and enhance electrical conductivity. Nitrogen doping can further improve the electrical conductivity and introduce defects in the carbon host. The results show that the FeS/NC-750 demonstrates a discharge capacity of 834 mA h g−1after 100 cycles at 200 mA g−1. The FeS/NC anode still has a high discharge specific capacity of 612.4 mAh g−1 even after 500 cycles at 1000 mA g−1. The simple strategy provides an inexpensive and straightforward strategy for conversion of FePc into available FeS/NC anode materials, which presents that FeS/NC electrode has potential application value in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

• A host material of sulfur with graphene-supported organic molecules is fabricated for Li–S batteries. • The organic molecule can anchor lithium polysulfides by forming a "Li···N" interaction. • The composite sulfur cathode presents improved electrochemical performance. Lithium–sulfur (Li–S) batteries with high theoretical energy density have been regarded as promising energy storage devices. However, the sluggish redox kinetics and shuttle effect of lithium polysulfides of sulfur cathodes remain obstacles to their development, especially with high sulfur content. Herein, we introduce the organic molecule of 3-amino-1,2,4-triazole (AT) on graphene (G) through π–π interactions as a sulfur host material to address the shuttle effect of lithium polysulfides. The molecular fragment of = N–C N– in AT as the active site can effectively anchor polysulfides existing as neutral molecules and free radicals in the electrolyte via "Li···N" interaction. Combined with the fast electron transport facilitated by the graphene, the redox kinetics of polysulfides is promoted. Thus, the electrochemical performance of Li–S batteries can be remarkably improved. The S/G-AT electrode displays excellent electrochemical performance in terms of a high initial capacity (1411 mAh/g at 0.2C), long-term cycling stability (799 mAh/g after 450 cycles at 1C), and superior rate performance (817 mAh/g at 10C). This study helps to utilize functional organic molecules for fabricating high-performance cathode materials for Li–S batteries. [ABSTRACT FROM AUTHOR]

A carbon nanotubes framework with nanoscale surface modification can guide homogeneous deposition of Li and restrain Li dendrite growth. [Display omitted] • A strategy of nano-ZIF-8 grows on the surface of the oxidized CNTs is proposed. • The oxidized CNTs and ZIF-8 nanoparticles with polar groups provide nucleation sites. • The microporous structure of ZIF-8 enlarges electrolyte adsorption capacity. • The CNTs@ZIF-8/Cu-Li anode effectively inhibit Li dendrite behavior. • The full cell is assembled to demonstrate the practical applications. Lithium (Li) metal is considered as an exciting anode candidate for next-generation high-performance Li metal batteries because of its high theoretical capacity and lowest redox potential. Unfortunately, unavoidable challenges consisting of dendritic behavior and volume change obstruct its widely commercial application. Here, a three-dimensional (3D) oxidized carbon nanotubes framework modified with lithiophilic nano-ZIF-8 particles (CNTs@ZIF-8) has been fabricated by a simple solution method as the collector for uniform Li deposition. The polar groups from oxidized CNTs and ZIF-8 nanoparticles provide adhesion sites for Li nucleation. Meanwhile, the nano-ZIF-8 particles with large specific surface area enhance electrolyte absorption, attracting electrolyte to the CNTs surface. The composite structure with nanoscale surface modification can guide homogeneous Li plating and restrain Li dendrites growth. As a consequence, the symmetrical cell of CNTs@ZIF-8/Cu–Li reveals a stable cycle time (over 1500 h) with a hysteresis voltage (9 mV) at 1 mA cm−2. The full cell assembled by LiFePO 4 (LFP) cathode and CNTs@ZIF-8/Cu–Li anode achieves outstanding rate and cycle performance which is superior to the CNTs/Cu–Li‖LFP, demonstrating that the CNTs@ZIF-8 is prospective for practical applications. [ABSTRACT FROM AUTHOR]

Metal doping plays a momentous role in heightening the electronic conductivity of Sn 4 P 3. This work proposes the facile synthesis of Fe-doped Sn 4 P 3 via a solid-state reaction process. The resulting Fe-doped Sn 4 P 3 is stacked by a great quantity of nanoparticles. As the ionic radius of Fe3+ (64.5 p.m.) is slightly smaller than that of Sn4+ (69 p.m.), Fe3+can easily dope into the structure of Sn 4 P 3. The Sn 4 P 3 anode with 5% Fe doping delivers a larger initial discharge capacity of 1105.1 mAh/g and coloumbic efficiency of 86.2%. After 200 cycles, a high discharge capacity of 972.4 mAh/g is reached, while the discharge capacity of un-doped Sn 4 P 3 anode merely maintains at about 423.3 mAh/g. As an inactive matrix, Fe atoms can disperse among Sn atoms, thus inhibiting the aggregation of Sn atoms during cycling. The results display that Fe doping in Sn 4 P 3 structure is extremely vital to heighten the architecture stability and electrochemical performance. This facile solid-state reaction process can be enlarged to the manufacture of other metal-doped Sn 4 P 3 in the field of lithium-ion batteries. [Display omitted] • Fe-doped Sn 4 P 3 was prepared by a solid-state reaction process. • The Sn 4 P 3 anode with 5% Fe doping achieves superior lithium storage properties. • Fe doping in Sn 4 P 3 structure is vital to heighten the structure stability. [ABSTRACT FROM AUTHOR]