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Summary: Despite being established as the most popular commercial energy storage system (ESS), lithium‐ion batteries (LIBs) are still facing practical issues due to their high cost and limited availability of the lithium source. Sodium‐ion batteries (SIBs), which have economic and environmental costs, but on‐par performance compared to LIBs, are now being considered as the next‐generation ESS. Herein, we report a facile and mass‐scalable synthesis of SnS2 nanosheets grafting on porous g‐C3N4 via direct solid‐state reaction from tin (IV) acetate and thiourea as precursors. The synthesized SnS2@g‐C3N4 composites served as an anode active material for SIBs with outstanding performances in terms of high capacity and ultralong cycling stability. The optimum anode delivered an initial discharge capacity of 1350.7 mAh g−1 and the first coulombic efficiency of 55.13%. However, this composite can offer a remarkable charge capacity of 919.6 and 602.7 mAh g−1 after 400 and 3000 cycles at specific currents of 500 and 2000 mA g−1, respectively. The enhancement in the cyclability of the obtained composites is attributed to the presence of g‐C3N4 as a scaffolding material effectively relieving serious strains induced by the volume variation of SnS2 during sodium storage. The high exfoliation of SnS2 nanosheets with larger interlayer spacing as well as the presence of a self‐induced internal electric field formed at the heterointerface of SnS2 and g‐C3N4 enables the enhanced transport of electrons and sodium ions, accompanied by the improvement in their electrochemical performance. [ABSTRACT FROM AUTHOR]

Tin dioxide (SnO 2 ) nanosheets/graphitic carbon nitride (g-C 3 N 4 ) composite was prepared by a hydrothermal method using mercapto acetic acid as the morphology directing agent in an acidic medium. The as-obtained composite was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope, and X-ray photoelectron spectroscopy; the results of this study show that in the composite, SnO 2 nanosheets with a thickness in the range ∼20–25 nm dispersed well on the g-C 3 N 4 . The lithium storage capability of the composite was investigated. The cycling performance of the composite was improved and is believed to be attributed by the presence of g-C 3 N 4 support. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights: • Composites of SnO 2 nanosheets on GO, g-C 3 N 4 and GO/g-C 3 N 4 supports were prepared. • Lithium storage performance for the composites was investigated. • The GO/g-C 3 N 4 support causes a better cycling performance for lithium storage. Abstract SnO 2 /graphite oxide/g-C 3 N 4 composite was synthesized by hydrothermally growing SnO 2 nanosheets on graphite oxide/g-C 3 N 4 using tin dichloride and mercapto acetic acid as tin source and structure-directing agent for SnO 2 nanosheets, respectively. For comparison, SnO 2 /graphite oxide and SnO 2 /g-C 3 N 4 composites were prepared with the same procedure except different supports. The obtained composites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, thermogravimetric-differential thermal analysis and electrochemical properties. The results show that the SnO 2 /graphite oxide/g-C 3 N 4 composite with the graphite oxide/g-C 3 N 4 support enhanced reversible capacity and cycling performance for lithium storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sn/g-C 3 N 4 composite was prepared using a simple chemical reduction method. • The cycling performance of the Sn/g-C 3 N 4 composite anode was significantly improved compared to pure Sn. • The presence of g-C 3 N 4 support as a buffer material led to an enhancement in mechanical strength for the composite anode. In this work, the Sn/g-C 3 N 4 composite was successfully synthesized via a facile chemical reduction method, in which Sn nanoparticles dispersed well on the porous framework of g-C 3 N 4. The composite is used as anode material for Lithium-ion battery, which exhibits significantly improved cycling performance compared to the pure Sn. This result is due to the significant contribution of the g-C 3 N 4 support in preventing volume change during lithiation/delithiation process of Sn. [ABSTRACT FROM AUTHOR]

[Display omitted] • Facile one-step synthesis of the SnS 2 @g-C 3 N 4 composites. • Significant enhancement in the electrochemical performance of the SnS 2 @g-C 3 N 4 composites. • Large contribution of pseudocapacitive effect. • Clarifying the lithium storage mechanism of the SnS 2 @g-C 3 N 4 composites. Today, the demand of high performance and low-cost anodes for lithium ion batteries becomes more serious to meet the requirement of electric vehicles and portable devices. In this study, a facile synthesis technique using a solid state reaction has been successfully applied for SnS 2 @g-C 3 N 4 composites. The obtained composites are constructed by SnS 2 nanosheets well-dispersed in porous matrix of g-C 3 N 4. The enhancement in the specific capacity, rated performance, and cycling behavior of the SnS 2 @g-C 3 N 4 composites is assigned to the buffering effect of the large-surface-area g-C 3 N 4 matrix as well as the predominant contribution of pseudocapacitive effect. The improved mobility of charge carriers is raised from not only the high exfoliation of the SnS 2 nanosheets, the high porosity of the composites but also the formation of heterointerfaces between semiconductors of SnS 2 and g-C 3 N 4. Accordingly, an internal electric field is generated inside the synthesized composites, which accelerates the migration of electrons and lithium ions. [ABSTRACT FROM AUTHOR]