Confined reaction inside nanotubes： New approach to mesoporous g-C3N4 photocatalysts

Mesoporous g-C3N4 nanorods （NRs） are synthesized through the nano-confined thermal condensation of cyanamide in silica nanotubes （NTs） with porous shells.The gas bubbles retained during condensation and the limited cyanamide precursor inside the silica NTs lead to the formation of mesoporous g-C3N4.This nano-confined reaction is an alternative method to the traditional templating process for the synthesis of mesoporous materials.The as-prepared mesoporous g-C3N4 NRs exhibit remarkably improved photocatalytic activity and high stability in water splitting and degradation of Rhodamine B compared with bulk g-C3N4.

Layer-controlled 2D Sn_(4)P_(3) via space-confined topochemical transformation for enhanced lithium cycling performance

Topochemical transformation has emerged as a promising method for fabricating two-dimensional (2D) materials with precise control over their composition and morphology. However, the large-scale synthesis of ultrathin 2D materials with controllable thickness remains a tremendous challenge. Herein, we adopt an efficient topochemical synthesis strategy, employing a confined reaction space to fabricate ultrathin 2D Sn_(4)P_(3) nanosheets in large-scale. By carefully adjusting the rolling number during the processing of Sn/Al foils, we have successfully fabricated Sn_(4)P_(3) nanosheets with varied layer thicknesses, achieving a remarkable minimum thickness of two layers (~ 2.2 nm). Remarkably, the bilayer Sn_(4)P_(3) nanosheets display an exceptional initial capacity of 1088 mAh·g^(−1), nearing the theoretical value of 1230 mAh·g^(−1). Furthermore, we reveal their high-rate property as well as outstanding cyclic stability, maintaining capacity without fading more than 3000 cycles. By precisely controlling the layer thickness and ensuring nanoscale uniformity, we enhance the lithium cycling performance of Sn_(4)P_(3), marking a significant advancement in developing high-performance energy storage systems.

Confining MoS_(2) nanocrystals in MOF-derived carbon for high performance lithium and potassium storage

Developing an efficient synthesis protocol to simultaneously control 2D nanomaterials’size and dispersion is the pivot to optimize their electrochemical performance.Herein,we report the synthesis of uniform MoS_(2) nanocrystals well-anchored into the void space of porous carbon(donated as MoS_(2)3C hybrids)by a simple confined reaction in metal–organic framework(MOF)during carbonization process.The strong confinement effect refrain MoS2 growth and aggregation,generating abundant active centers and edges,which contribute fast lithium/potassium reaction kinetics.In addition to the hybridization with the derived carbon,the MoS_(2)3C hybrids exhibit rapid Liþtransfer rate(~109 cm^(2) s 1)and greatly improved electronic conductivity.Consequently,the MoS23C hybrids show ultrafast rate performances and satisfactory cycling stabilities as anode materials for both lithium and potassium ion batteries.This work demonstrates a universal tactic to achieve high dispersive 2D nanomaterials with tailorable particle size.

Using graphene to suppress the selenization of Pt for controllable fabrication of monolayer PtSe2

Platinum diselenide(PtSe2)is a promising transition metal dichalcogenide(TMDC)material with unique properties.It is necessary to find a controllable fabrication method to bridge PtSe2 with other two-dimensional(2D)materials for practical applications,which has rarely been reported so far.Here,we report that the selenization of Pt(111)can be suppressed to form a Se intercalated layer,instead of a PtSe2 monolayer,by inducing confined conditions with a precoating of graphene.Experiments with graphene-island samples demonstrate that the monolayer PtSe2 can be controllably fabricated only on the bare Pt surface,while the Se intercalated layer is formed underneath graphene,as verified by atomic-resolution observations with scanning transmission electron microscopy(STEM)and scanning tunneling microscopy(STM).In addition,the orientation of the graphene island shows a negligible influence on the Se intercalated layer induced by the graphene coating.By extending the application of 2D confined reactions,this work provides a new method to control the fabrication and pattern 2D materials during the fabrication process.