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Metal compound/carbon (MC/C) composites are one of the key materials for advancing energy storage, catalysis, sensing and other technologies, yet their synthesis is hampered by complex and inefficient methods that compromise the carbon/non-carbon interface compatibility. This study introduces a strategy for synthesizing MC/C composites, leveraging coordination chemistry between chitosan and metal ions to enhance interfacial interactions and achieve uniform multi-phase interfaces. During the one-step heat treatment process of chitosan-based coordination polymers, metal compound nanoparticles can be formed in situ within a carbon matrix, thereby eliminating the need for environmentally harmful precursors and overcoming the issue of low reaction efficiency caused by traditional solid-state mixing techniques. The as-synthesized typical Ni3S2/C composite exhibits high reversible capacity (1434 mA h g−1, 250 cycles at 0.05 A g−1), and superior rate capability (capacity retention exceeds 41% with a 40-fold enhancement of current density) when used as the anode of lithium-ion batteries. This general and scalable synthesis strategy for MC/C composites opens new avenues for the development of high-performance anode materials for lithium-ion batteries, offering a pathway to green, sustainable and cost-effective energy storage solutions. [ABSTRACT FROM AUTHOR]

Effectively preserving the high specific surface area and diverse heteroatom functional groups of biomass-derived porous carbons is crucial, but there is still work to be done in developing energy storage technologies with high-rate survival and superior, long-lasting capacitive activity. Herein, we report an efficient method for ammonium persulfate assisted synthesis of ant-nest-like hierarchical porous carbons (AH-PCs) originating from chitosan for superior-quality supercapacitors and zinc-ion hybrid capacitors (ZIHCs). The extensive cross-linking of chitosan results in an ant-nest-like hierarchical structure and a high specific surface area of 3518 m2 g−1, with 83.48% micropores, ideal for ion transport. The AH-PCs exhibit a high heteroatom (N and O) content of 21.49%. Employed as electrode materials for supercapacitors, the AH-PCs exhibit an extremely high 500 F g−1 specific capacitance in a 6 M KOH electrolyte. With a remarkable capacity retention rate of 71.65%, the symmetric supercapacitor produces a high capacitance of 329.4 F g−1 at a 0.5 A g−1 discharge rate, and it retains 236 F g−1 even at 20 A g−1. Impressively, after 400 000 cycles at 10 A g−1, the capacity retention rate remains at 94.9%, with an average loss of just 0.00001275% per cycle. In a 1 M Na2SO4 electrolyte, a high energy density of 37.69 W h kg−1 can be achieved at 225 W kg−1. Used as positive electrode materials of ZIHCs, a high energy density of 137.61 W h kg−1 can be yielded. Remarkably, even after 20 000 cycles at a high current density of 20 A g−1, the capacity retention rate remains at 100% with an ultra-low self-discharge rate of 2.67 mV h−1. These exceptional electrochemical properties hold significant promise for advanced supercapacitors and ZIHCs. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) have been considered as a promising and competitive option for novel energy storage due to their intrinsically remarkable energy density and low cost. Unfortunately, the commercialization of LSBs is plagued with several notorious drawbacks, especially the shuttle effect of lithium polysulfides (LiPSs) and their sluggish redox kinetics. In this respect, a consensus has been reached that only integrating proper physical/chemical regulation can realize effective LiPS management and lead to overall optimization of LSBs. Zeolitic imidazolate framework (ZIF)-derived nanomaterials have excellent physical/chemical configurations such as high specific surface area (SSA), sufficient pores, and ample electrocatalytic sites, which make them versatile materials for comprehensive LiPS management. Herein, this timely review first provides a detailed illustration of the progress in physical/chemical methods of LiPS management for LSBs and then discusses the methodology of how to prepare ZIF-derived nanomaterials with various morphologies, structures, and chemical components for the confinement and utility of LiPSs. Finally, we systematically summarize current shortcomings and latent prospects of the application of ZIF-derived nanomaterials. We firmly believe that this review can provide beneficial inspiration for the future development of ZIF-derived nanomaterials for application in LSBs. [ABSTRACT FROM AUTHOR]

Intimately coupling metal chalcogenides (MCs) with carbon materials is critical for boosting their application performances. However, since MCs and carbon materials are usually two types of incompatible materials, a non-uniform carbon/MC interface is easily formed, especially for multidimensional nanostructures. Herein, we propose an interfacial engineering strategy to enhance the interaction between a three-dimensional nanonetwork-structured carbon aerogel (CA) and MCs. The key to this strategy is the introduction of substantial oxygen-containing functional groups into the CA, which greatly improves its compatibility with MC precursors, and thus enables MCs to grow on the CA framework homogeneously. The optimized CA/MC interface enables extremely compact bonding interaction between the CA and MC nanosheets. Benefitting from a well-organized structure, the synthesized CA@MC composites show remarkable potassium-ion storage performances and electrochemical kinetic properties. As a demonstration, the CA@MoS2 composites show high reversible capacity (389 mA h g−1 at 100 mA g−1), excellent rate performance (capacity retention exceeds 40% with a 5-fold increase of the current density) and an enhanced ion diffusion rate when used as an anode material for potassium-ion batteries. [ABSTRACT FROM AUTHOR]

The effective preparation of high porosity carbonaceous electrode materials is a critical and challenging issue for obtaining superior supercapacitors. In this work, a novel KCl-assisted KOH strategy is developed for the preparation of Moringa oleifera branch-based porous carbon materials (PCMs). Benefiting from the liquid environment of in situ formed molten salts, KCl-assisted KOH activation can effectively decrease the usage of KOH, and thus increase the yield of PCMs from 9.8% to 15.6% whilst maintaining their high porosity. Therefore, the obtained PCMs possess a high specific surface area (i.e., 2314–3470 m2 g−1) and pore volume (i.e., 0.94–1.69 cm3 g−1). When used in supercapacitors, a typical PCM electrode exhibits a high capacitance of 421 F g−1 at 0.5 A g−1 and with an excellent cyclic stability of 4% capacity decay after 20 000 charge/discharge cycles in 6 M KOH electrolyte. Additionally, a maximum energy density of 33.0 W h kg−1 can be achieved at 224.0 W kg−1. This attractive electrochemical performance shows PCMs to be a promising material for use in supercapacitors. Furthermore, this research provides a cost-effective and promising route for the preparation of porous carbon with high porosity. [ABSTRACT FROM AUTHOR]

Two-dimensional carbon-based composite nanosheets (2D-CCNSs) are expected to be promising electrodes for fast charging lithium-ion batteries. Even though synthesis procedures exist for these materials, current approaches often require rigid reaction conditions and complicated synthetic steps. Herein, we develop a facile and general approach to fabricate a new type of 2D-CCNSs and demonstrate its superiority as a high-rate anode for lithium-ion batteries. It is found that the introduction of a nanocellulose as building unit can guide itself to self-assemble with polydopamine and metal ions to form a 2D inorganic–organic hybrid, which can be directly transformed into 2D-CCNSs after a carbonization treatment without structural deterioration. Unlike common 2D-CCNSs with a pure graphitic or amorphous carbon framework, the as-constructed materials possess a distinctively heterogeneous carbonaceous skeleton comprising graphitic nanorods with a crystalline framework and amorphous carbon with a microporous structure. The synthetic strategy is also demonstrated to be general for embedding numerous metal oxides, such as Fe2O3, CoO, NiO nanoparticles, into the carbon framework just by adjusting the types of metal ions. Profiting from the well-orchestrated structure, the as-prepared 2D-CCNSs exhibit impressive high-rate lithium ion storage performance. For instance, after being fully charged within 40.8 s, a long discharge time as high as 342 min can be achieved accompanied with a high and stable reversible capacity of 560 mA h g−1. [ABSTRACT FROM AUTHOR]

As an environmentally unfriendly and low-cost by-product produced during the manufacturing of pulp and paper, ca.170 million tons of black liquor is generated per year in the world. Efforts to effectively convert black liquor into high-value products are very critical but remain challenging. Herein, we successfully prepare porous carbons using black liquor powders as precursors through a simple carbonization technique without any extra activators or templates. The black liquor-derived porous carbons (BL-PCs) exhibit a remarkable three-dimensional (3D) honeycomb-like morphology and a hierarchical porous structure. Additionally, the disordered degree of BL-PCs can be controlled by simply regulating carbonization temperature. A combination of 3D honeycomb-like morphology, hierarchical porous structure and decreased disordered degree not only contributes to the fast electrolyte ion transport, but also improves the rate performance and cycling stability when BL-PCs are used as anode materials for sodium-ion batteries. A typical BL-PC anode exhibits attractive electrochemical performances, including high rate capability and long-term cycling stability. [ABSTRACT FROM AUTHOR]

A new kind of hollow carbon nanosphere with an ordered mesoporous shell structure is prepared and demonstrated to have improved performances in practical application areas involving fast ion transport. [ABSTRACT FROM AUTHOR]

An efficient self-crosslinking procedure to reasonably construct porous shells is reported for the synthesis of yolk–shell Au@microporous carbon nanospheres. [ABSTRACT FROM AUTHOR]

In this work, we report a universal KOH-free strategy to fabricate two-dimensional nitrogen-doped carbon nanosheets from edible oil residues. The saponification process and novel mild activators are introduced for the first time to optimize the microstructure of the nitrogen-doped carbon nanosheets. The resulting carbon nanosheets present a high specific surface area (2470 m2 g−1), wide pore size distribution (0.5–60 nm), and high nitrogen content (4.96%). As electrode materials for supercapacitors, the as-prepared nitrogen-doped carbon nanosheets exhibit a high specific capacitance of 340 F g−1 at a current density of 0.5 A g−1 and retain a high capacitance of 282 F g−1 at a very high current density of 50 A g−1, with no capacitance attenuation seen after 20 000 charge/discharge cycles in 6.0 M KOH electrolyte. The as-fabricated carbon nanosheet-based symmetric cell manifests a maximum energy density of 55.5 W h kg−1 at the power density of 369 W kg−1 and retains a high energy density of 32.3 W h kg−1 at 6180 W kg−1 in 1.0 M LiPF6 electrolyte. Experimental results reveal that this study provides an efficient and universal strategy for novel pre-treatment and KOH-free activation of nitrogen-doped carbon nanosheets with high specific surface area for high-rate and high-energy supercapacitors. [ABSTRACT FROM AUTHOR]

Lamellar carbon frameworks with covalently connected alternate layers of porous carbon nanosheets (PCNs) and porous carbon spacers (PCSs) were successfully fabricated based on the stepwise crosslinking of self-assembled lamellar block copolymers. The intrinsic porous structure of PCSs can maximize the utilization of well-developed surfaces/interfaces of the PCNs. [ABSTRACT FROM AUTHOR]

Sustainable synthesis methods for the production of porous carbon with appropriate structural properties for use as supercapacitor electrodes are in high demand. Generally, activation is the most convenient and effective method to increase the surface area of carbon materials. However, the existing activation methods usually suffer from a low yield and low specific surface area; so the search for a new activation agent capable of preparing porous carbon with both a high yield and large surface area remains a great challenge. Here, a new and efficient activation agent copper chloride (CuCl2) is proposed for the production of porous carbon using rape pollen biomass as the carbon precursor. The advantages of using CuCl2 to fulfil synchronous carbonization and activation can be ascribed to the following features: (i) excellent ability to generate micropores in biomass; (ii) a high yield of porous carbon; (iii) low-destruction of the natural structure of the precursor; (iv) high retention of heteroatoms. The as-prepared rape pollen carbon (RPC) exhibits a porous structure with a large specific surface area (2488 m2 g−1), sphere-like structure and high heteroatom content. More importantly, the RPC exhibits a high yield of porous carbon of up to 37.6 wt% based on the raw rape pollen. Furthermore, the RPC electrode exhibits extremely high specific capacitance (390 F g−1 at 0.5 A g−1) and long cycling stability (retaining 92.9% after 10 000 cycles at 20 A g−1) in 6.0 M KOH aqueous electrolyte, and a high energy density of 26.8 W h kg−1 at a power density of 181.4 W kg−1 in 1.0 M Na2SO4 aqueous electrolyte. This method has universal significance in producing highly porous and high-performance carbons from biomass for various energy storage/conversion energy storage applications. [ABSTRACT FROM AUTHOR]

The development of an effective route to high-performance carbonaceous electrode materials derived from low-cost biomass is critical but remains challenging for supercapacitors. Here we propose a new and cost-effective way to produce chitosan-based hierarchical porous carbons by the union of hydrothermal carbonization and chemical activation. The key to this preparation strategy is the utilization of acetic acid as an additive for hydrothermal carbonization, which not only favors the construction of a conducive environment for accessibility of activator KOH, but also leads to the formation of a rigid semi-carbonized framework substrate for generating an ultrahighly porous structure. Thus, our synthetic approach allows for a lower amount of activation agent and lower heating temperature when compared with normal chemical activation techniques, providing a more efficient way to produce ultrahigh-surface-area carbon materials. The as-prepared hierarchical porous carbon possesses a unique honeycomb-like framework and the highest BET surface area of 3532 m2 g−1 among all the carbon materials derived from chitosan. The combination of the hierarchical pore structure for rapid ion diffusion and the ultrahigh surface area for sufficient electrochemically active sites significantly improves the material's capacitive behaviors. An unusually high capacitance of 455 F g−1, an excellent cycling stability with 99% capacity retention over 20 000 cycles in KOH aqueous electrolyte, and a high energy density of 20.6 W h kg−1 at a power density of 226.8 W kg−1 in 1.8 V Na2SO4 aqueous supercapacitors have been obtained, demonstrating that the chitosan-based hierarchical porous carbons developed here are very attractive for application in supercapacitors. [ABSTRACT FROM AUTHOR]

Mesocrystals are advantageous in providing a large specific surface and favorable transport properties, and have been extensively studied for energy-related applications including supercapacitors, solar cells, lithium-ion batteries, and catalysis. However, the practical applications of mesocrystals are hindered by many obstacles, such as high cost, complicated synthesis processes, and utilization of deleterious additives. Herein, we report a facile one-step and additive-free route for the controllable synthesis of NiO mesocrystals (NOMs) with a cuboctahedral morphology and layered hierarchical structures consisting of self-assembled NiO nanosheets. When employed as an electrode material for supercapacitors, the as-prepared NOMs exhibited an exceptional electrochemical performance such as an ultrahigh reversible specific capacity of ca. 1039 F g−1 at a current density of 1.0 A g−1 and excellent cycling stability (ca. 93% capacitance retention after 10 000 charge/discharge cycles). Moreover, an all-solid-state hybrid supercapacitor based on hierarchical NOMs and three-dimensional nitrogen-doped graphene manifested a high energy density of 34.4 W h kg−1 at a power density of 150 W kg−1 in 2.0 M KOH aqueous electrolyte. These results further demonstrate the potential of NiO mesocrystals as a promising electrode material by constructing a hierarchical mesostructure, which can improve the electrochemical performance for energy storage. The outstanding electrochemical performance may be attributed to their hierarchical mesostructure that can effectively enhance the electrical conductivity and avoid the aggregation of NiO nanosheets, and the exposed {100} facets with a high electrochemical activity. [ABSTRACT FROM AUTHOR]

Due to unique high-surface-area ordered mesoporous channels interconnected with 3D network-like mesopores and π–π interactions between carbon frameworks and analytes, the as-prepared ordered mesoporous carbon-coated fiber exhibited a large adsorption amount, fast mass transport and high sensitivity. [ABSTRACT FROM AUTHOR]

The pioneered construction of novel monodisperse hollow and yolk–shell structured periodic mesoporous polymer nanoparticles was reported by the development of an efficient reactive interface-guided co-assembly approach. [ABSTRACT FROM AUTHOR]

The interconnected ordered pore channels facilitate faster permeation of Li+ ions during the charge–discharge process than the isolated ordered pore channels, resulting in significantly enhanced capacities, better rate capabilities and more remarkable cycling stability. [ABSTRACT FROM AUTHOR]

A facile route to fabricate nitrogen-doped ordered nanoporous carbons (NONCs) was developed based on in situ polydopamine coating onto the pore surface of ordered nanoporous silica. The NONC exhibits very attractive capacitive properties, including unusually large capacitances up to 538 F g−1, highly efficient electrochemically active surface area and good cycling stability. [ABSTRACT FROM AUTHOR]

A unique hierarchical architecture is successfully constructed in a wormhole-like mesopore structure viaa multiple nanocasting route. This novel type of hierarchical porous carbon (HPC) consists of three-dimensional ordered macropores (ca.150 nm) with interconnecting pore windows, and the walls of these macropores are rich in wormhole-like mesopores (ca.2.7 nm) and large spherical mesopores (ca.10 nm), as well as a significant microporosity, presenting a macro-meso-microporous structure with a three-dimensional interconnectivity. Such a hierarchically porous structure may provide fine diffusion pathways for reaction species, which is demonstrated by the experimental result of an enhanced performance in a supercapacitor. For example, with the introduction of a hierarchical porous structure for fast transport and effective access of ions, the as-prepared HPC exhibits a specific capacitance as high as 247 F g−1, whereas traditional wormhole-like mesoporous carbon has only a specific capacitance of 176 F g−1. [ABSTRACT FROM AUTHOR]

In the present paper, we demonstrate the importance of the role of a mass transport pathway (MTP) in wormholelike mesoporous carbon (WMC) through studying the ion diffusion behaviors within two different wormholelike mesopore networks with and without MTP. Our results reveal that the introduction of MTP is very helpful in improving ion diffusion properties. The as-prepared WMC with a MTP of ca.9.7 nm exhibits notably better electric double layer performance as compared to the conventional WMC without a MTP. For example, even at the quick sweep rate of 50 mV s−1, the surface specific capacitance of the former is 21.6 μF cm−2, which is almost 4 times as high as that of the latter (5.5 μF cm−2). [ABSTRACT FROM AUTHOR]

The ordered 2D reverse hexagonal pore morphology facilitates rapid ion diffusion more than the disordered wormhole-like pore morphology, thus leading to superior electrochemical properties such as rate capabilities. [ABSTRACT FROM AUTHOR]

A novel type of hierarchical porous carbon has been successfully prepared by constructing intra- and inter-sphere –CO– crosslinking bridges of monodisperse styrene–divinylbenzene copolymer nanospheres. The –C6H4– crosslinking bridges ensure good stability of the nanospheres during swelling and crosslinking, and the –CO– crosslinking bridges play an important role in achieving good nanostructure inheritability during carbonization. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) with carbon aerogel (CA) as conducting filler has been synthesized by an in situ chemical oxidative polymerization method. Scanning electron microscopy, infrared spectra, cyclic voltammetry and X-ray diffraction indicate that the three-dimensional carbon nano-network of CA is entirely buried inside the PANI matrix and its introduction basically does not change the structure of PANI. The electrochemical performances of the as-prepared PANI materials with CA filler are evaluated by means of galvanostatic charge-discharge test, cyclic voltammetry and electrochemical impedance spectroscopy. It is found that the electrochemical performances of PANI are notably improved due to the introduction of CA filler. For example, when operating at a large current density of 50 mA cm(-2), CA-modified PANI with the optimal CA/aniline ratio of 1.0 wt% exhibits a specific capacitance as high as 226 F g(-1), whereas neat PANI has only 89 F g(-1). The CA modification mechanism of PANI has been discussed in detail.