Uniform small-sized MoS2 from novel solution-based microwave-assisted method with exceptional reversible lithium storage properties

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.

Bi-MOF derived micro/meso-porous Bi@C nanoplates for high performance lithium-ion batteries

Micro/meso-porous Bi@C nanoplates are synthesized by pyrolyzing Bi-based metal-organic frameworks (MOFs) prepared by a microwave-assisted hydrothermal method to overcome huge volume expansion and pulverization of anode materials during battery operation. The Bi@C nanoplates are composed of ∼10-50 nm Bi nanoparticles in an amorphous carbon shell. The material shows very high capacity (556 mA h g-1) after 100 cycles at 100 mA g-1 and good cycling performance. Moreover, the Bi@C nanoplates perform well at high current densities and have excellent cyclic stability; their capacity is 308 mA h g-1 after 50 cycles and 200 mA h g-1 after 1000 cycles at 3000 mA g-1. The outstanding performance of this anode is due to the nanosized Bi and amorphous carbon shell. The nanosized Bi reduces the diffusion length of Li ions, while the amorphous carbon shell improves the electrical conductivity of the anode and also restrains the pulverization and aggregation of the metal during cycling. The proposed hierarchical micro/meso-porous materials derived from MOFs are a new type of nanostructures that can aid the development of novel Bi-based anodes for LIBs.

An ultra-small few-layer MoS2-hierarchical porous carbon fiber composite obtained via nanocasting synthesis for sodium-ion battery anodes with excellent long-term cycling performance

Rational fabrication of anode electrodes for sodium-ion batteries remains a challenge due to the problem of sluggish Na+ diffusion kinetics, large volume expansion etc. Significant efforts, such as fabricating carbon composites and novel nanostructures, have been devoted to the development of anode materials. Herein, an ultra-small few-layer MoS2 nanostructure confined on a hierarchical porous carbon fiber composite was synthesized through the nanocasting route using a novel hierarchical porous carbon fiber as the template. As an anode material, the composite displays outstanding electrochemical performance for sodium-ion batteries. For instance, it delivers high reversible capacities (491 mA h g-1 after 50 cycles at 0.1 A g-1), high rate performance (387 mA h g-1 at 2 A g-1) and long-term cycling stability (234 mA h g-1 at 1 A g-1 after 3000 cycles). Note that it shows one of the best long-term cycling properties reported to date for MoS2-based anode materials for sodium-ion batteries. This regulation strategy may offer new insights into the fabrication of high-performance anode materials for sodium-ion batteries.