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Transition metal chalcogenides (TMCs) belongs to the most promising class of materials with unique properties and widespread applications. Coupling with carbon materials allows further enhancement of the specific performance of TMCs by mitigating their intrinsic deficiencies. However, the synthesis of a wide variety of TMCs/carbon composites with a universal strategy especially in a scalable manner remains challenging. In this work, by utilizing the gas‐liquid interfaces in viscous gel precursors, an "all‐in‐one" blowing strategy is proposed to achieve the synchronous growth of TMCs and carbon nanosheets, obviating the additional chalcogenization process. The generality of the proposed blowing strategy is validated by the fabrication of 32 different TMCs/carbon composites, including 24 binary TMCs, 4 ternary TMCs and 4 high‐entropy sulfides. In‐depth mechanistic study is accomplished by investigating the physical evolution of blowing process and accompanying chemical reactions systematically. Also, the structure of the resulting foam is adjustable by controlling the heating rate and viscosity of the precursors is demonstrated. As an illustrative example for the application of energy storage, MoS2xSe2(1‐x)@CNS exhibits great Li+ storage capacity and cycling stability. Overall, this methodology serves as an effective general strategy for the rational discovery of TMCs/carbon composites and inorganic solid foams. [ABSTRACT FROM AUTHOR]

To address the plight of huge volume change and low intrinsic conductivity of NiO as anodes for lithium ion batteries (LIBs), we construct carbon-encapsulated NiO nanoparticles (NiO@C) on porous reduced graphene oxide (pRGO) matrix (NiO@C/pRGO). This is achieved by a smartly programmed annealing process using Ni(OH) 2 /RGO hybrid aerogel as precursor. It is noteworthy that our synthetic strategy unifies the formation of pores on RGO and inner carbon shell on NiO nanoparticles simultaneously and realizes the application of pRGO in such dual-carbon armored electrodes for the first time. When used as anodes for LIBs, NiO@C/pRGO electrode displays a high rechargeable specific capacity of 1003 mAh g −1 at a current density of 200 mA g −1 , superior rate capability, and good cycling performance up to 1000 cycles. Such outstanding electrochemical performance is mainly ascribed to the dual-carbon decoration, which can not only accommodate large volume changes of NiO, but also stabilize the NiO against self-agglomeration and greatly improve the charge transfer efficiency of the electrode. It is expected that such dual-carbon protection and porous carbon matrix can be extended to prepare other electrodes with well-defined nanoarchitecture and high efficiency for lithium transition. [ABSTRACT FROM AUTHOR]

Despite the fascinating Li storage properties of organic carbonyl compounds, e.g., high therotical capacity and fast kinetics, it is still lack of a facile and effective way that capable of large-scale producion of advanced carbonyl cathodes for Li-ion batteries (LIBs). Here, a generic strategy is proposed by combining sonication and hydrothermal techniques for scalable synthesis of high performance organic carbonyl cathodes for LIBs. A series of commercialized vat dyes with abundant electroactive conjugated carbonyl groups are confined in between the graphene layers, forming a compatible 3D hybrid architecture. The unique structure affords good Li+ ions accessibility to the electrode and short Li+ ions diffusion length. Meanwhile, each sandwiched graphene layer functions as a miniature current collector, ensuring fast electron transport throughout the entire electrode. Consequently, the cathodic performances of LIBs using the composites as electrodes, for example, Vat Green 8/graphene, Vat Brown BR/graphene, and Vat Olive T/graphene, possess high specific capacity, exceptional cycling stability, and excellent rate capability. The effect of vat dye content on the morphology, structure, and the final electrochemical performance of the composites is investigated as well. This work provides a versatile and low-cost platform for large-scale development of advanced organic-based electrodes toward sustainable energy fields. [ABSTRACT FROM AUTHOR]

Transition metal oxides anodes of lithium ion batteries (LIBs) usually suffer from low reaction kinetics with slow charge/ions transfer resulting from severe volume variation. In this work, thin porous copper shell is homogeneously coated on the CoO nanowires forming CoO/Cu hetero-structured arrays. Cu shell not only acts as a conductive network, but also serves as a protective “armor” layer to keep electrode stable upon cycling. Meanwhile, 3D porous architecture with large surface area is well preserved in the CoO/Cu hetero-structured arrays. Due to enhanced electron/ion transfer characteristics and strengthened electrode structure, the as-prepared CoO/Cu hetero-structured arrays exhibit much higher electrochemical reactivity with lower polarization and better reversibility due to the introduction of thin Cu shell. Additionally, enhanced discharge capacity and large-rate performances are also demonstrated in the CoO/Cu hetero-structure arrays when compared with the pure CoO nanowires counterpart. [ABSTRACT FROM AUTHOR]

A novel three-dimensional (3D) Fe 2 O 3 /reduced graphene oxide (RGO) hydrogel (FGH) is prepared by a facile hydrothermal strategy. In this composite hydrogel, RGO sheets self-assemble into an interconnected macroporous framework and Fe 2 O 3 nanotubes encapsulate into RGO layers. The FGH delivers high rate capacities of 850, 780, 550, and 400 mAh/g at current densities of 200, 400, 600, and 800 mA/g, respectively. The specific capacity can still maintain at ∼600 mAh/g after 70 cycles, which greatly outperforms that of pure Fe 2 O 3 nanotubes (∼60 mAh/g after 70 cycles). The improved electrochemical performance is ascribed to the unique macroscopic structure which is beneficial for enlarging the active surface area, shortening the electron/ion pathway, accommodating the volume change of Fe 2 O 3 nanotubes, and preventing the aggregation of both Fe 2 O 3 nanoparticles and RGO sheets. [ABSTRACT FROM AUTHOR]

Urgent and heavy demand of high energy/power density lithium-ion batteries (LIBs) challenges the ultimate limit of commercial anodes. Herein, enlightened by the extra capacity on transition metal oxides (TMO) anodes derived from the transition metal (TM) catalytic effect on reversible solid-electrolyte interface (SEI) films, a ternary composite consisting of TM, TMO, and carbon matrix, namely TM/TMO/carbon, is proposed as a novel and high-efficiency anode prototype. In this electrode design, TMO not only serve as active material but also pulverizes the TM nanoparticles via the conversion reaction during cycling. Pulverized TM nanoparticles can activate and/or promote the reversible transformation of SEI films more efficiently. And carbon matrix ensures the electronic conductivity and integrity of the overall electrode during multiple electrochemical reactions. As a proof-of-concept demonstration, NiCo-NiCo 2 O 4 @carbon nanotubes (NC-NCO@CNTs) is synthesized by a bottom-up strategy via in-situ growth on a simplified chemical vapor deposition (CVD) process. As designed, the NC-NCO@CNTs keeps gaining extra capacity upon cycling, delivering an unceasingly increased capacity up to 1324 mAh g −1 (500 mA g −1 ), splendid rate performance (945 mAh g −1 at 1000 mA g −1 , 696 mAh g −1 at 2000 mA g −1 ), and ultralong lifespan (2200 cycles). Detailed electrochemical investigation reveals a transformation of lithium storage mechanism from battery-type conversion reaction to pseudocapacitive electrochemical interfacial reaction arising from SEI films. It is believed that our work offers a novel and effective prototype for designing high energy/power density anodes for LIBs. [ABSTRACT FROM AUTHOR]

Currently, high-temperature thermal failure hinders the development of lithium-ion batteries (LIBs). Interfacial side reaction of electrolyte and electrode is the main cause of thermal failure at high temperature. Explicitly, suppressing interfacial side reactions at high temperatures can help the research of capacitive energy storage electrodes. While, thermo-electrochemical inert alumina can be facilitated to solve this problem. In this paper, pitaya configuration of nano-alumina islands uniformly dispersed in carbon matrix can be achieved from NOTT-300(Al). Nano-alumina contributes to the structural stability of porous carbon during carbonization and lithium deintercalation. And nano-alumina islands are effective in suppressing interfacial side reactions at high temperatures. Thus, NC-3 exhibits competitive specific capacity (717.1 mAh/g) and cycling stability (99.15% after 500 cycles). NC-3's capacity was confirmed to be mainly attributed to capacitive energy storage mechanism. This study provides a new research paradigm for nano-alumina to improve the high-temperature thermal stability management of LIBs. Nano-alumina islands enable superior capacitive lithium-ion storage of pitaya configuration porous carbon. [Display omitted] • Pitaya configuration of nano-alumina islands uniformly dispersed in carbon matrix can be achieved from NOTT-300(Al). • Nano-alumina contributes to the structural stability of porous carbon during carbonization and lithium deintercalation. • Nano-alumina islands are effective in suppressing interfacial side reactions at high temperatures. • NC-3's capacity can be mainly contributed to capacitive energy storage mechanism. • NC-3 exhibits competitive specific capacity (717.1 mAh/g) and cycling stability (99.15% after 500 cycles). [ABSTRACT FROM AUTHOR]

3D N-doped honeycomb-like carbon nanocage@carbon nanotubes (NHCN@CNT)- based monolithic electrodes are constructed via chemical blowing for supercapacitor and lithium-ion battery. [Display omitted] • A new blowing method with extra carbon source is developed for NHCN@CNT. • The inactive Ni catalysts for the growth of CNT have been in-situ transformed into active NiS/Ni 2 P. • The NHCN@CNT@Ni 2 P exhibits superior electrochemical performance in both supercapacitor and LIB. • Good energy storage ability mainly originates from the rational composition and structure design. Three-dimensional (3D) pyrolytic carbon has risen to prominence as an effective kind of active material or substrate for energy-related applications. However, the poor electrical conductivity and relatively low capacity still remain obstacles for its further use. Herein, we report a smartly designed chemical blowing strategy towards the implantation of highly conductive carbon nanotubes (CNTs) into 3D N-doped honeycomb-like carbon nanocage (NHCN) by introducing an extra carbon source during the Ni(NO 3) 2 -induced polymer blowing process. It is noted that Ni(NO 3) 2 has dual functions in our work: blowing the polymer and catalyzing the growth of CNTs. More importantly, the residual inactive Ni catalysts in the NHCN@CNT are in-situ converted into active NiS/Ni 2 P via a post sulfidizing/phosphating treatment rather than being removed. As a proof-of-concept demonstration, the resulted NHCN@CNT (154.4F g−1 at 1 A/g) and NHCN@CNT@Ni 2 P (1416.8F g−1 at 1 A/g) both perform well as supercapacitor (SC) electrodes. Moreover, the NHCN@CNT@Ni 2 P also manifests good lithium storage ability (462.8 mAh g−1 at 0.1 A/g). Thus, it is assumed that the intelligently constructed NHCN@CNT in this work hold great potential to be an attractive carbon material for energy storage devices. [ABSTRACT FROM AUTHOR]

NCM811 precursor with concentration gradients is prepared by adjusting the feeding method of MnSO 4 ·H 2 O in the co-precipitation method. X-ray diffraction patterns show that the precursors have good crystal structure of β-Ni(OH) 2. Energy dispersive X-ray spectroscopy shows that the precursor sample performs relatively gentle concentration gradient distributions and scanning electron microscope presents that the precursor delivers a good sphericity and concentrated particle size distribution. The prepared NCM811 material also has good crystal structure and gentle concentration gradient distributions. Electrochemical tests show that it exhibits a better cycle performance of 98.0% capacity retention after 200 cycles at the current density of 1C, which is obviously better than the intrinsic material (87.5%). X-ray diffraction patterns presents unchanged crystal structure and transmission electron microscopy presents clear lattice fringes after 200 cycles. In contrast, part of crystal structure of the intrinsic material transforms into NiO 2 phase and Ni in Li layer occupying is very serious after 200th cycles and its lattice fringes are distorted with irregular direction. All of these results exhibit that the side reactions between nickel ions and the electrolyte can be effectively suppressed through the design of gradient structure, so it can improve the structural stability and cycle stability. • NCM811 precursor with concentration gradients is prepared by a simple controllable co-precipitation method. • The prepared NCM811 material has good crystal structure and gentle concentration gradient distributions. • The gradient material exhibits a better structural stability and cycle stability than the intrinsic material. • The mechanism why the concentration gradient structure can improve material performance is studied. [ABSTRACT FROM AUTHOR]