High-Performance and Reactivation Characteristics of High-Quality, Graphene-Supported SnS2 Heterojunctions for a Lithium-Ion Battery Anode

Fast Energy Storage of SnS2 Anode Nanoconfined in Hollow Porous Carbon Nanofibers for Lithium-Ion Batteries

The development of conversion-typed anodes with ultrafast charging and large energy storage is quite challenging due to the sluggish ions/electrons transfer kinetics in bulk materials and fracture of the active materials. Herein, the design of porous carbon nanofibers/SnS2 composite (SnS2 @N-HPCNFs) for high-rate energy storage, where the ultrathin SnS2 nanosheets are nanoconfined in N-doped carbon nanofibers with tunable void spaces, is reported. The highly interconnected carbon nanofibers in three-dimensional (3D) architecture provide a fast electron transfer pathway and alleviate the volume expansion of SnS2 , while their hierarchical porous structure facilitates rapid ion diffusion. Specifically, the anode delivers a remarkable specific capacity of 1935.50 mAh g-1 at 0.1 C and excellent rate capability up to 30 C with a specific capacity of 289.60 mAh g-1 . Meanwhile, at a high rate of 20 C, the electrode displays a high capacity retention of 84% after 3000 cycles and a long cycle life of 10 000 cycles. This work provides a deep insight into the construction of electrodes with high ionic/electronic conductivity for fast-charging energy storage devices.

Microwave-Assisted Fabrication of High Energy Density Binary Metal Sulfides for Enhanced Performance in Battery Applications

Nanomaterials have found use in a number of relevant energy applications. In particular, nanoscale motifs of binary metal sulfides can function as conversion materials, similar to that of analogous metal oxides, nitrides, or phosphides, and are characterized by their high theoretical capacity and correspondingly low cost. This review focuses on structure-composition-property relationships of specific relevance to battery applications, emanating from systematic attempts to either (1) vary and alter the dimension of nanoscale architectures or (2) introduce conductive carbon-based entities, such as carbon nanotubes and graphene-derived species. In this study, we will primarily concern ourselves with probing metal sulfide nanostructures generated by a microwave-mediated synthetic approach, which we have explored extensively in recent years. This particular fabrication protocol represents a relatively facile, flexible, and effective means with which to simultaneously control both chemical composition and physical morphology within these systems to tailor them for energy storage applications.

A Comprehensive Compilation of Graphene/Fullerene Polymer Nanocomposites for Electrochemical Energy Storage

Electricity consumption is an integral part of life on earth. Energy generation has become a critical topic, addressing the need to fuel the energy demands of consumers. Energy storage is an offshoot of the mainstream process, which is now becoming a prime topic of research and development. Electrochemical energy storage is an attractive option, serving its purpose through fuel cells, batteries and supercapacitors manipulating the properties of various materials, nanomaterials and polymer substrates. The following review presents a comprehensive report on the use of carbon-based polymer nanocomposites, specifically graphene and fullerene-based polymer nanocomposites, towards electrochemical energy storage. The achievements in these areas, and the types of polymer nanocomposites used are listed. The areas that lack of clarity and have a dearth of information are highlighted. Directions for future research are presented and recommendations for fully utilizing the benefits of the graphene/fullerene polymer nanocomposite system are proposed.

Synthesis and Applications of Dimensional SnS2 and SnS2/Carbon Nanomaterials

Dimensional nanomaterials can offer enhanced application properties benefiting from their sizes and morphological orientations. Tin disulfide (SnS₂) and carbon are typical sources of dimensional nanomaterials. SnS₂ is a semiconductor with visible light adsorption properties and has shown high energy density and long cycle life in energy storage processes. The integration of SnS₂ and carbon materials has shown enhanced visible light absorption and electron transmission efficiency. This helps to alleviate the volume expansion of SnS₂ which is a limitation during energy storage processes and provides a favorable bandgap in photocatalytic degradation. Several innovative approaches have been geared toward controlling the size, shape, and hybridization of SnS₂/Carbon composite nanostructures. However, dimensional nanomaterials of SnS₂ and SnS₂/Carbon have rarely been discussed. This review summarizes the synthesis methods of zero-, one-, two-, and three-dimensional SnS₂ and SnS₂/Carbon composite nanomaterials through wet and solid-state synthesis strategies. Moreover, the unique properties that promote their advances in photocatalysis and energy conversion and storage are discussed. Finally, some remarks and perspectives on the challenges and opportunities for exploring advanced SnS₂/Carbon nanomaterials are presented.

Heterostructural Sn/SnO2 microcube powders coated by a nitrogen-doped carbon layer as good-performance anode materials for lithium ion batteries

The nitrogen-doped carbon (NC) coating encapsulating heterostructural Sn/SnO₂ microcube powders (Sn/SnO₂@NC) are successfully fabricated through hydrothermal, polymerization of hydrogel, and carbonization processes, in which the SnO precursor powders exhibit regular microcube structure and uniform size distribution in the presence of optimized N₂H₄·H₂O (3.0 mL of 1.0 mol/L). Interestingly, the precursor powders are easily subjected to a disproportionated reaction to yield the desirable heterostructural Sn/SnO₂@NC microcube powders after being calcined at 600 °C in N₂ atmosphere in the presence of home-made hydrogel. The coin cells assembled with the Sn/SnO₂@NC electrode present a high initial discharge specific capacity (1058 mAh g^-1 at 100 mA g^-1), improved rate capability (an excellent D_Li+ value of 2.82 × 10^-15 cm² s^-1) and enhanced cycling stability (a reversible discharge specific capacity of 486.5 mAh g^-1 after 100 cycles at 100 mA g^-1). The enhanced electrochemical performance can be partly ascribed to the heterostructural microcube that can accelerate the transfer rate of lithium ions by shortening the transmission paths, and be partly to the NC coating that can accommodate the volume effect and contribute to partial lithium storage capacity. Therefore, the strategy may be able to extend the fabrication of Sn/SnO₂ heterostructural microcube powders and further application as promising anode materials in lithium ion batteries.

Phosphorus Doping Induced the Co-Construction of Sulfur Vacancies and Heterojunctions in Tin Disulfide as a Durable Anode for Lithium/Sodium-Ion Batteries

The reasonable design of electrode materials with heterojunction and vacancy is a promising strategy to elevate its electrochemical performances. Herein, tin-based sulfide composites with heterojunction and sulfur vacancy encapsulated by...

Heterostructures between a tin-based intermetallic compound and a layered semiconductor for gas sensing

SnS2 nanoplates are used as sacrificial templates to facilitate the in situ growth of intermetallic compound Pt3Sn nanoparticles. The Pt3Sn/SnS2 heterostructures show promise for selective NO2 sensing due to the favored gas adsorption and gas-solid charge transfer on Pt3Sn, combined with the optimized film conductance and formation of ohmic-type Pt3Sn/SnS2 heterointerfaces.

Binary Iron Sulfide as a Low-Cost and High-Performance Anode for Lithium-/Sodium-Ion Batteries

Iron-based sulfides have been deemed as an appealing anode material for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) for their high theoretical capacity and low cost. However, their practical application is limited by drastic volume expansion during cycling and low-intrinsic electronic conductivity. In this work, we report a FeS₂/Fe₇S₈-rGO composite synthesized via a facile solvothermal method as an LIB/SIB anode. The FeS₂/Fe₇S₈-rGO anode exhibits an excellent Li-storage capacity of 514 mAh g^-1 at 2.0 A g^-1 after 3000 cycles and a Na-storage capacity of 650 mAh g^-1 at 0.2 A g^-1 after 250 cycles, respectively. The rGO matrix is deemed responsible for providing good electron conduction and alleviating volume expansion during cycling. The electrokinetic analysis confirms a large portion of intercalational pseudocapacitance as a major contribution to the superior rate performance. In situ X-ray diffraction further reveals details of a combined intercalational and conversional Li-ion storage mechanisms in this Fe-sulfide-based anode. Finally, density functional theory calculations suggest that there exists a synergistic effect at the heterointerface between FeS₂ and Fe₇S₈ to promote electrokinetics.

Facile Green Synthesis of Pseudocapacitance-Contributed Ultrahigh Capacity Fe2(MoO4)3 as an Anode for Lithium-Ion Batteries

The investigation into the use of earth-abundant elements as electrode materials for lithium-ion batteries (LIBs) is becoming more urgent because of the high demand for electric vehicles and portable devices. Herein, a new green synthesis strategy, based on a facile solid-state reaction with the assistance of water droplets' vapor, was conducted to prepare Fe₂(MoO₄)₃ nanosheets as anode materials for LIBs. The obtained sample possesses a two-dimensional stacked nanosheet construction with open gaps providing a much higher surface area compared to the bulk sample conventionally synthesized. The nanosheet sample delivers an ultrahigh reversible capacity (1983.6 mA h g^-1) at a current density of 100 mA g^-1 after 400 cycles, which could be related to the contribution of pseudocapacitance. The enhancement in cyclability and rated performance with an interesting increased capacity could be caused by the effect of electrochemical milling and the in situ formation of metallic particles in its lithium-ion storage mechanism.

Carbon-Based Polymer Nanocomposite for High-Performance Energy Storage Applications

In recent years, numerous discoveries and investigations have been remarked for the development of carbon-based polymer nanocomposites. Carbon-based materials and their composites hold encouraging employment in a broad array of fields, for example, energy storage devices, fuel cells, membranes sensors, actuators, and electromagnetic shielding. Carbon and its derivatives exhibit some remarkable features such as high conductivity, high surface area, excellent chemical endurance, and good mechanical durability. On the other hand, characteristics such as docility, lower price, and high environmental resistance are some of the unique properties of conducting polymers (CPs). To enhance the properties and performance, polymeric electrode materials can be modified suitably by metal oxides and carbon materials resulting in a composite that helps in the collection and accumulation of charges due to large surface area. The carbon-polymer nanocomposites assist in overcoming the difficulties arising in achieving the high performance of polymeric compounds and deliver high-performance composites that can be used in electrochemical energy storage devices. Carbon-based polymer nanocomposites have both advantages and disadvantages, so in this review, attempts are made to understand their synergistic behavior and resulting performance. The three electrochemical energy storage systems and the type of electrode materials used for them have been studied here in this article and some aspects for example morphology, exterior area, temperature, and approaches have been observed to influence the activity of electrochemical methods. This review article evaluates and compiles reported data to present a significant and extensive summary of the state of the art.

In situ chemically encapsulated and controlled SnS2 nanocrystal composites for durable lithium/sodium-ion batteries

SnS2 as the promising anode for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) still encounters the undesirable rate performance and cycle stability. Herein, a unique stable structure is developed, where the SnS2 nanocrystals (NCs) are sturdily encapsulated by carbon shells anchored on a reduced graphene oxide (rGO) via the one-pot solvothermal process. The well-controlled carbon shells provide the enduring protection for SnS2 NCs through C-S covalent bonds from the corrosion of electrolyte and pulverization of structure. Moreover, both experimental results and density functional theory (DFT) calculations demonstrate that the carbon protective shell effectively enhances the structure stability and conductivity of the resulting materials. Interestingly, the size of SnS2 NCs and the thickness of carbon shells are accurately controlled by regulating the content of glucose. Aided by the advanced electron/ion transfer kinetics and structure stability, the SnS2-based electrode exhibits desired lithium/sodium storage performance and unprecedented long-term cycling stability (capacity retention of 74.7% after 1000 cycles at 2 A g-1 for LIBs and 102% after 200 cycles at 500 mA g-1 for SIBs). This work develops a method for promoting the practical applications and large-scale production of SnS2 composites for energy storage devices.