Three-dimensional Carbon Research Articles

Multilevel spatial confinement of transition metal selenides porous microcubes for efficient and stable potassium storage

Recently, potassium-ion batteries (PIBs) have been considered as one of the most promising energy storage systems; however, the slow kinetics and large volume variation induced by the large radius of potassium ions (K+) during chemical reactions lead to inferior structural stability and weak electrochemical activity for most potassium storage anodes. Herein, a multilevel space confinement strategy is proposed for developing zinc-cobalt bimetallic selenide (ZnSe/Co0.85Se@NC@C@rGO) as high-efficient anodes for PIBs by in-situ carbonizing and subsequently selenizing the resorcinol–formaldehyde (RF)-coated zeolitic imidazolate framework-8/zeolitic imidazolate framework-67 (ZIF-8/ZIF-67) encapsulated into 2D graphene. The highly porous carbon microcubes derived from ZIF-8/ZIF-67 and carbon shell arising from RF provide rich channels for ion/electron transfer, present a rigid skeleton to ensure the structural stability, offer space for accommodating the volume change, and minimize the agglomeration of active material during the insertion/extraction of large-radius K+. In addition, the three-dimensional (3D) carbon network composed of graphene and RF-derived carbon-coated microcubes accelerates the electron/ion transfer rate and improves the electrochemical reaction kinetics of the material. As a result, the as-synthesized ZnSe/Co0.85Se@NC@C@rGO as the anode of PIBs possesses the excellent rate capability of 203.9 mA h g−1 at 5 A g−1 and brilliant long-term cycling performance of 234 mA h g−1 after 2,000 cycles at 2 A g−1. Ex-situ X-ray diffraction (Ex-situ XRD) diffraction reveals that the intercalation/de-intercalation of K+ proceeds through the conversion-alloying reaction. The proposed strategy based on the spatial confinement engineering is highly effective to construct high-performance anodes for PIBs.

Rational design of Ni nanoparticles loaded porous N-doped carbon nanostructures for efficient hydrogenation reduction of Cr(VI): Performance, critical role of hydrogen species and mechanism insight

Catalytic hydrogenation via formic acid (FA) activation is an important way for the control of Cr(VI)-contaminated water. In the present study, three-dimensional porous N-doped carbon nanostructures loaded with quasi-spherical Ni nanoparticles (Ni@NC) are rationally prepared by a facile carbonization strategy and developed as a robust catalyst to effectively activate FA for hydrogenation reduction conversion of Cr(VI) to Cr(III). Such carbon nanostructures with large specific surface areas and abundant mesopores not only protect the anchored Ni nanoparticles from poisoning, but also coordinate with Ni nanoparticles to diversify active sites, significantly promoting Cr(VI) reduction efficiency. The optimal Ni@NC catalyst presents the excellent activity for catalytic FA activation and achieves high-efficiency Cr(VI) reduction, delivering the enhanced rate constant of 0.059 min−1 and favorable k-value of 3.15 μmol s−1 g−1, attributing to collaborative cooperation of high-electron-density Ni sites and self-polarized NC. More importantly, the Ni@NC catalyst exhibits robust tolerance of coexisting ions and good reusability for Cr(VI) reduction in acidic environment. Spectroscopic analysis and electrochemical evaluation unveil the critical role of the surface-bonded Ni–Hads* species and hydrogen radicals (·H) in-situ generated in Ni@NC/FA system for hydrogenation reduction of Cr(VI).

Watermelon Flesh-Like Ni3 S2 @C Composite Separator with Polysulfide Shuttle Inhibition for High-Performance Lithium-Sulfur Batteries.

The shuttle effect limits the practical application of lithium-sulfur (Li-S) batteries with high specific capacity and cheap price. Herein, a three-dimensional carbon substrate containing Ni3 S2 nanoparticles is created to modify the separator. The in situ optical visualization battery proves that the material can realize the rapid conversion of Li2 S6 . Moreover, the impact of lithium-ion diffusion on the reactions in the cell is investigated, and the mechanism of Ni3 S2 @C in the cell is proposed based on the "adsorption-diffusion-conversion" mechanism. The "adsorption-diffusion-conversion" process of polysulfide is carried out on the surface of the composite separator, showing positive effects on the inhibition of polysulfide shuttle and the promotion of conversion. The separator is modified to improve sulfur utilization and reduce dead sulfur accumulation through a strategy of chemical immobilization and physical blocking. This helps to bridge the existing gaps of Li-S batteries.

Boosted lithium storage performance by local build-in electric field derived by oxygen vacancies in 3D holey N-doped carbon structure decorated with molybdenum dioxide

• 3D porous N-doped carbon decorated with MoO 2 nanoparticles were synthesized; • Oxygen vacancies were introduced into the prepared composites; • The differential charge density distribution and density of states were applied; • A 918.2 mAh g −1 at 0.1 A g −1 after 130 cycles were obtained for Li storage; • The kinetic analysis of MoO 2 /C electrodes for Li storage was carried out. Three-dimensional holey nitrogen-doped carbon matrixes decorated with molybdenum dioxide (MoO 2 ) nanoparticles have been successfully synthesized via a NaCl-assisted template strategy. The obtained MoO 2 /C composites offered multi-advantages, including higher specific surface area, more active sites, more ions/electrons transmission channels, and shorter transmission path due to the synergistic effect of the uniformly distributed MoO 2 nanoparticles and porous carbon structure. Especially, the oxygen vacancies were introduced into the prepared composites and enhanced the Li + intercalation/deintercalation process during electrochemical cycling by the Coulomb force. The existence of the local built-in electric field was proved by experimental data, differential charge density distribution, and density of states calculation. The uniquely designed structure and introduced oxygen vacancy defects endowed the MoO 2 /C composites with excellent electrochemical properties. In view of the synergistic effect of the uniquely designed morphology and introduced oxygen vacancy defects, the MoO 2 /C composites exhibited superior electrochemical performance of a high capacity of 918.2 mAh g –1 at 0.1 A g –1 after 130 cycles, 562.1 mAh g –1 at 1.0 A g –1 after 1000 cycles, and a capacity of 181.25 mAh g –1 even at 20.0 A g –1 . This strategy highlights the path to promote the commercial application of MoO 2 -based and other transition metal oxide electrodes for energy storage devices.

Facile fabrication of Zr-based metal–organic framework/Ketjen black-carbon nanotubes composite sensor for highly sensitive detection of methyl parathion

A novel methyl parathion (MP) electrochemical sensor was fabricated from the multifunctional composite of Zr-based metal–organic framework (UiO-66) and Ketjen black-carbon nanotubes (KB-CNTs), which achieved the sensitive detection of MP in food samples. For the UiO-66/KB-CNTs composite, Zr-based UiO-66 with Zr-OH groups possessed good affinity for phosphate groups on methyl parathion molecules, which enhanced the selective recognition and enrichment capability towards MP, and KB-CNTs possessed three-dimensional interconnected carbon conductive network with synergistic point-line carbon conductive contact, which showed excellent electrical conductivity. Moreover, KB with pearl chain-like structure and more conductive contact points realized the full contact between KB-CNTs and UiO-66 with Zr-OH groups. The fabricated UiO-66/KB-CNTs/GCE sensor showed good MP detection performance with low limit of detection of 1.53 nM in linear MP concentration range of 0.005–12 µM. Moreover, the fabricated sensor showed good repeatability, reproducibility, and selectivity. A good practical feasibility can be achieved at the UiO-66/KB-CNTs/GCE sensor for the detection of MP in grape juice and apple juice samples (Recovery rate: 96.14–102.93, relative standard deviation: 2.17%-4.95%).

In situ construction of oxygen deficient MoO3-x nanosheets/porous graphitic carbon nitride for enhanced photothermal-photocatalytic hydrogen evolution

In this work, the photocatalysts containing oxygen-deficient molybdenum oxide and macroscopic three-dimensional porous graphitic carbon nitride phase composite (MoO3-x/PCN) were prepared by in situ self-assembly method. The crystal phase and structure were characterized by XRD, XPS, FT-IR, SEM, and TEM measurements. Hydrogen production results showed that introducing of MoO3-x resulted in a higher hydrogen production rate of MoO3-x/PCN composite catalyst than that of PCN. Among them, the highest hydrogen production rate of 2336.15 μmol g−1 h−1 was achieved for MoO3-x-10/PCN, which was 2.23 times higher than PCN (1048.00 μmol g−1 h−1). When the reaction system temperature was 100 °C, the photothermal hydrogen production rate of MoO3-x-10/PCN was 8902.00 μmol g−1 h−1, which was 3.81 times higher than that at room temperature. PL spectra, UV–vis spectra and photoelectrochemical measurements showed that the localized surface plasmon resonance (LSPR) effect of MoO3-x effectively enhanced the photo response range and increased the temperature of the reaction system. ESR measurements showed that he composites should follow the Z-scheme charge transfer mechanism, the electrons in the CB of MoO3-x further migrate to the VB of PCN, which hinders the charge complexation in MoO3-x and PCN, improving the hydrogen production activity. This study provides a new idea for constructing a plasma-based photothermal synergistic catalytic hydrogen production strategy.

Core–shell Ni3Sn2@C particles anchored on 3D N-doped porous carbon skeleton for modulated electromagnetic wave absorption

Synthesizing multi-component composites via a straightforward, reliable, and scalable approach has been challenging. Herein, a three-dimensional nitrogen-doped porous carbon decorated with core–shell Ni3Sn2@carbon particles (3D N-PC/Ni3Sn2@C) was customized through a simple salt-template pyrolysis approach. The formed Ni3Sn2 particles are perfectly surrounded by crystalline carbon layers and embedded in 3D carbon walls during pyrolysis. The dual protection of crystalline carbon layers and porous carbon walls guarantees the electrical conductivity and stability of Ni3Sn2. The intriguing 3D and core–shell structure coupled with the introduction of multiple components empowers the composite with rich heterogeneous interface and conductive network, and contributes to the lightweight, corrosion resistance, oxidation resistance, and superior stability of electromagnetic (EM) wave absorbers. The N-PC/Ni3Sn2@C possesses the minimum reflection loss (RLmin) of –54.01 dB and wide effective absorption bandwidth (EAB) of 7.36 GHz under a low filler content of less than 10%. The concept in the work proposes a facile, eco-friendly, and scalable pathway for the synthesis of other heterogeneous structures of EM wave absorbers.

Synergistic constraint and conversion of lithium polysulfide using a 3D hollow carbon interlayer in ultrahigh sulfur content Li-S batteries

Low sulfur content and inevitable polysulfide shuttle effect have always been the critical obstacle of the practical application of high-energy–density lithium sulfur batteries. Herein, a waste passiflora edulis peel derived in-situ N-doping porous carbon (PINPC) combined with three-dimensional hollow carbon cloth interlayer (3DHCI) was designed and constructed by facile simultaneous activation/carbonization. The abundant porous structure and nitrogen heteroatom doping of the PINPC not only significantly confine the soluble polysulfides through the physical and chemical adsorption, but also the high conductivity of the 3DHCI effectively accelerate the conversion reaction of polysulfides encapsulated in the unique hollow carbon skeletons. Owing to the synergetic enhancement of the PINPC and 3DHCI, the sulfur contents of the corresponding sulfur cathode composites are easily regulated from 70 wt% to 95 wt%, whilst exhibiting excellent electrochemical performances. The PINPC/S with a sulfur content of 70 wt% and 3DHCI interlayer obtains a high initial discharge capacity of 1032 mAh·g−1 and then retains 954 mAh·g−1 at 0.2 C after 200 cycles. At 2 C, a durable cycle life with capacity retention of 86% can be achieved up to 500 cycles. Even with an ultrahigh sulfur content of 95 wt%, the relatively high initial discharge capacity of 692 mAh·g−1 and capacity retention of 96 % are also achieved at 0.2 C after 200 cycles. This work offers a potential design for high-performance lithium sulfur batteries simultaneously with a high sulfur content.

MnO2 nanoflowers loaded on three-dimensional interconnected bacterial cellulose-derived honeycomb-like carbon for high-performance supercapacitors

Bacterial cellulose (BC) has been considered to be an ideal substrate for electrode materials due to its characteristics of natural abundance and wide range of sources. Controlling the microscopic morphology of electrode materials can enhance the capacity of BC materials effectively. However, most of the remaining BC derived carbon exhibit morphology of fibers, and the effective method for porous morphology need further studies, let alone the electrochemical properties of the materials used as electrode active material. Here, we prepared 3D interconnected mesoporous honeycomb-like carbon by pyrolysis of purified bacterial cellulose (3DIHBC). Then MnO2 with flower-like morphology was then grown on the 3D carbon with a simple hydrothermal method. The prepared 3DIHBC/MnO2 electrode delivers a reversible specific capacitance of 170F g−1 at 1 A g−1, and also retains 76% impressive long-term cycling stability after 5000 cycles at 10 A g−1 in an aqueous electrolyte. This is a highly cost-effective method for the preparation of 3DIHBC/MnO2 composites, and the rational use of cheap biomass carbon can improve the drawback of poor cyclic stability of metal oxides, which is important for environmental protection and mass-producible energy storage.

A systematic study on Equisetum ramosissimum Desf. derived honeycomb porous carbon for supercapacitors: Insight into the preparation-structure-performance relationship

It is always of considerable significance for the development of high-performance carbon-based supercapacitors to regulate the porosity and understand the preparation-structure-performance relationship. In this work, a KOH-assisted hydrothermal pre-treatment combined with pyrolysis strategy is successfully employed to fabricate N-doped honeycomb-like three-dimensional porous carbon from Equisetum ramosissimum Desf. weeds. The pore structure is well-regulated by tuning the KOH concentration and carbonization temperature, thus optimizing the electrochemical properties. Three types of pore structures are proposed, and their differences and connections in terms of preparation and electrochemical performance are systematically explored. The carbon sample with the optimized pore structure delivers a high specific capacitance of 427 F g−1 at 0.2 A g−1 in the aqueous KOH electrolyte. When assembled into an aqueous symmetric supercapacitor device, the energy density reaches up to 30.9 Wh kg−1 at a power density of 500 W kg−1. The results indicate that a moderate Vmirco/Vmeso should play the key role in the excellent rate capability, while the co-contribution of double-layer capacitance and pseudo-capacitance as well as the rational pore size regulation should be responsible for the high specific capacitance.

Cicada-Wing-Inspired Highly Sensitive Tactile Sensors Based on Elastic Carbon Foam with Nanotextured Surfaces.

Electronic devices with tactile and pressure-sensing capabilities are becoming increasingly popular in the automatic industry, human motion/health monitoring, and artificial intelligence applications. Inspired by the natural nanotopography of the cicada wing, we propose here a straightforward strategy to fabricate a highly sensitive tactile sensor through nanotexturing of erected polyaniline (PANI) nanoneedles on a conductive and elastic three-dimensional (3D) carbon skeleton. The robust and compressible carbon networks offer a resilient and conducting matrix to catering complex scenarios; the biomimetic PANI nanoneedles firmly and densely anchored on a 3D carbon skeleton provide intimate electrical contact under subtle deformation. As a result, a piezoresistive tactile sensor with ultrahigh sensitivity (33.52 kPa-1), fast response/recovery abilities (97/111 ms), and reproducible sensing performance (2500 cycles) is developed, which is capable of distinguishing motions in a wide pressure range from 4.66 Pa to 60 kPa, detecting spatial pressure distribution, and monitoring various gestures in a wireless manner. These excellent performances demonstrate the great potential of nature-inspired tactile sensors for practical human motion monitoring and artificial intelligence applications.

Free-Standing Carbon Nanofiber Composite Networks Derived from Bacterial Cellulose and Polypyrrole for Ultrastable Potassium-Ion Batteries.

Carbon materials derived from bacterial cellulose have been studied in lithium-ion batteries due to their low cost and flexible characteristics. However, they still face many intractable problems such as low specific capacity and poor electrical conductivity. Herein, bacterial cellulose is used as the carrier and skeleton to creatively realize the composite of polypyrrole on its nanofiber surface. After carbonization treatment, three-dimensional carbon network composites with a porous structure and short-range ordered carbon are obtained for potassium-ion batteries. The introduction of nitrogen doping from polypyrrole can increase the electrical conductivity of carbon composites and provide abundant active sites, improving the comprehensive performance of anode materials. The carbonized bacterial cellulose@polypyrrole (C-BC@PPy) anode exhibits a high capacity of 248 mA h g-1 after 100 cycles at 50 mA g-1 and a capacity retention of 176 mA h g-1 even over 2000 cycles at 500 mA g-1. Combined with density functional theory calculations, these results indicate that the capacity of C-BC@PPy is contributed by N-doped and defect carbon composite materials as well as pseudocapacitance. This study provides a guideline for the development of novel bacterial cellulose composites in the energy storage field.

One step hot-pressing method for hybrid Li metal anode of solid-state lithium metal batteries

Safety issues induced by infinite anode volume change and uncontrolled lithium (Li) dendrite growth have become the biggest obstacle to the practical application of Li metal batteries. In addition, the traditional rolling method makes it difficult to manufacture thin Li foil with high mechanical strength and low Li content. Herein, a three-dimensional (3D) lithophilic carbon paper/copper (Cu) current collector hybrid anode with ultra-low Li metal content is prepared by a hot-pressing method. The highly reversible and stable lithiophilic layer LiCx formed in situ by heating/pressing treatment provides abundant nucleation sites and reduces the Li nucleation overpotential, thereby effectively suppressing Li dendrite growth. Moreover, the volume change and pulverization problems of Li metal anode during deposition/stripping also can be accommodated by the 3D skeleton. The optimization effect has been directly confirmed by in-situ optical and ex-situ scanning electron microscope observation. Therefore, highly stable performance (158.4 mA h g−1 at 2 C after 200 cycles with a capacity retention of 95.24%) in Li@LCP-Cu||NCM811 coin cell can be achieved. Furthermore, the solid-state battery assembled with the hybrid anode, poly(vinylidene fluoride) (PVDF)-based polymer electrolyte and polyethylene oxide (PEO) interface functional layer also exhibits the best electrochemical and safety performance, which also proves that the Li@LCP-Cu anode has great potential for application in solid-state batteries.

Studies on electromagnetic interference shielding effect mechanisms of leaf-like three-dimensional carbon nanotubes/graphene aerogel film and the composites with polydimethylsiloxane

The three-dimensional (3D) structure can improve electromagnetic interference (EMI) shielding effectiveness (SE) of carbon-materials, thereby satisfy the requirement of lightweight. Herein, a leaf-like 3D carbon nanotubes (CNTs)/graphene aerogel film (CGAF) is prepared in which the CNTs are seamlessly embedded in graphene, analogous to veins and mesophyll of a leaf, respectively. The assembly of mesophyll-like graphene into 3D materials not only improves EMI SE, but also changes the EMI shielding mechanism. The addition of veins-like CNTs further amplifies the change of EMI shielding mechanism. The total EMI SE (SEtot) of 3D CGAF is 26.6 dB, which was 3.0 dB and 5.1 dB higher than that of CGP (prepared by compressing CGAF) and GAF (CGAF without CNTs). Besides, the 3D structure makes the absorption SE (SEA) dominates the SEtot of CGAF, accounting for 66.5%, but the reflection SE (SER) is dominant in the SEtot of CGP and the theoretical SEtot of CGAF. This shows that 3D structure can improve the absorption effect by repeatedly reflecting electromagnetic waves (EMWs) from countless pore walls, and the addition of CNTs further synergizes this effect, thus enhancing the SEtot and SEA. Furthermore, the SEMA (SEtot divided by mass per unit area) of CGAF can reach 12091 dB cm2 g−1, which increases by 12.7% and 18.1% compared to CGP and GAF, respectively. In addition, by combining multilayer CGAF with polydimethylsiloxane (PDMS), the SEtot can reach 74.7 dB at 8.2 GHz, and its SEtot still retains 45.6 dB after 100 cycles of bending, still far above the industry standard (20 dB), showing excellent bending resistance.

In situ three-dimensional cross-linked carbon nanotube-interspersed SnSb@CNF as freestanding anode for long-term cycling sodium-ion batteries

Alloying-based material has achieved tremendous appealing being anode used in sodium‑ion batteries (SIBs) by virtue of its relatively giant sodium storage specific capacity along with low discharge platforms. Nevertheless, the sluggish ion transmission dynamics and the huge volume change during cycling induced irreparable particle pulverization and agglomeration result in collapse of electrode structure and deterioration of cycling properties. In this work, three-dimensional cross-linked carbon nanotube-interspersed SnSb@CNF integrated structure (SnSb@CNF/CNT) is designed and synthesized. In this ingenious nanostructure, CNTs interspersed between CNF frames play the role of electron transport and diffusion “bridges” for enhancing the electrical conductivity of anode materials and relieve aggregation of SnSb alloy particles, the N doped-CNFs serve as external frame could efficiently mitigate dramatic volume effect to maintain system integrity. Based on these constructive advantages, the elastic conductive system can be directly available as anode for SIBs, showing ultralong cycling performance of 210 mAh g−1 over 700 sodiation/desodiation processes with a current density of 0.5 A g−1, even 161 mAh g−1 following 1000 cycling under a high current density of 1 A g−1 accompanied by an almost 100% superb capacity retention ratio, as well as distinguished high rate performance (470 mAh g−1 with a returned current density of 0.05 A g−1). This work shed distinctive insight to construct in situ three-dimensional cross-linked freestanding alloying-based anode materials used in alternative electrochemical grid-scale application.

Multifunctional three-dimensional porous MOFs derived Fe/C/carbon foam for microwave absorption, thermal insulation and infrared stealth

Multifunctional microwave absorbing materials with properties of high absorbing performance, infrared stealth, thermal insulation are urgently required to cope with current complex and extreme electromagnetic environment. To solve this problem, a three-dimensional carbon foam (CF) was used as a matrix, and Fe/C nanocubes derived from Prussian Blue (PB) were uniformly distributed throughout the CF skeleton. Such design of Fe/C/CF porous structures enhanced the synergistic effects between dielectric and magnetic loss to reach a better absorbing performance. The minimum reflection loss (RL) of hybrid foam is −66.7 dB, and the widest effective absorbing bandwidth (EAB, RL < −10dB) is 6.34 GHz. Moreover, the hybrid foam showed remarkable infrared stealth and thermal insulation properties. The surface temperature of hybrid foam almost unchanged while it was heated under 100 °C for more than 1 h. It is noteworthy that the preparation process of hybrid foam was a facile, recycled, and low-cost strategy for achieving high-performance absorbing materials. Besides, the mentioned methods may provide inspirations for the preparation of high-performance microwave absorbing materials and increase the potential application fields in complex actual scenarios.

O-doped and nitrogen vacancies 3D C3N4 activation of peroxydisulfate for pollutants degradation and transfer hydrogenation of nitrophenols with water

A three-dimensional carbon nitride co-modified through oxygen doping and nitrogen vacancies was prepared via an ordinary hydrothermal and thermal polymerization reaction of dicyandiamide and polyethylene glycol-polypropylene glycol-polyethylene glycol triblock copolymer (PEPE-C3N4). The electronic structure of carbon and nitrogen was proven through solid-state nuclear magnetism and electron loss energy spectroscopy. Density functional theory calculations revealed reduced band gap and altered charge density. The results show that the PEPE-C3N4 constructed by O-doped and nitrogen vacancy released electrons to activate peroxodisulfate (PDS), in which the 1% PEPE-C3N4 in the photocatalytic PDS system showed about 12 and 30 times increase of the photodegradation of 2-mercaptobenzothiazole (MBT) and bisphenol A (BPA), respectively, compared to graphite-phase carbon nitride (g-C3N4). The degradation products of MBT and BPA were named according to applying liquid chromatography-mass spectrometry and conceivable degradation pathways proposed. Furthermore, 1% PEPE-C3N4 had the highest hydrogen production activity (8275.74 μmol•h−1•g−1); it completely hydrogenates 4-nitrophenol to 4-aminophenol after 2.5 h of simulated sunlight. Additionally, biomass was used instead of TEOA to measure the coupling operation of H2 generation and selective oxidation of 5-hydroxymethylfurfural (HMF) to 2, 5-furandicarboxaldehyde (DFF). The optimized PEPE-C3N4 demonstrated high efficiency for selective oxidation of HMF to DFF with simultaneous H2 co-production (1176.84 μmol•h−1•g−1 for H2 and 357.67 μmol•h−1•g−1 for DFF), 5.31 and 2.36 times more excellent than that of g-C3N4, respectively. This study outlines a way to devise photocatalysts for organic pollutant degradation and biomass value-added co-production of hydrogen.

ZIF-8-Derived Three-Dimensional Nitrogen-Doped Porous Carbon as a Pt Catalyst Support for Electrocatalytic Oxidation of Glucose in a Glucose Fuel Cell

ZIF-8-Derived Three-Dimensional Nitrogen-Doped Porous Carbon as a Pt Catalyst Support for Electrocatalytic Oxidation of Glucose in a Glucose Fuel Cell

Construction of MoS2-ZnS@C Heterostructures by Multiple Organic Framework Combination for Fast and Stable Sodium/Potassium Storage

The establishment of three-dimensional structures, carbon coating, and proper defects is an effective strategy to improve electrochemical performance of molybdenum sulfide. In this work, carbon-coated MoS2-ZnS (MoS2-ZnS@C) heterostructures were constructed by treating the MOF precursor with a one-step sulfurization/carbonization strategy. The MoS2-ZnS@C heterostructures not only introduce abundant C–S–C and C–N bonds which contribute to ion storage with enhancive active sites but also effectively accelerate ion diffusion and reaction kinetics. The corresponding reaction mechanism was revealed via XRD and HR-TEM tests. The anode of MoS2-ZnS@C heterostructures shows outstanding rate capability (309 mAh g–1 at 10 A g–1) and long cycle stability (343 mAh g–1 after 1200 cycles at 5 A g–1) in sodium-ion batteries (SIBs). Meantime, the MoS2-ZnS@C heterostructure anode also exhibits enhanced potassium storage performances, delivering a superior rate capability (80 mAh g–1 at 5 A g–1) and superior long cycle performance (297 mAh g–1 after 100 cycles at 0.5 A g–1). In addition, a high specific capacity of 270 mAh g–1 is achieved at 1 A g–1 in a full cell made up of MoS2-ZnS@C/ether-based electrolyte/Na3V2(PO4)3. The construction of heterostructures for improving the electrochemical performance can also be applicable to other battery material fields.

Facile fabrication of three-dimensional carbon foam from fractionated corncob lignin

Facile fabrication of three-dimensional carbon foam from fractionated corncob lignin