TiN as a simple and efficient polysulfide immobilizer for lithium–sulfur batteries

Abstract

HF-etched TiN is used to replace carbon as a novel polysulfide immobilizer to achieve a high-performance sulfur cathode.

Mesoporous Carbon@Titanium Nitride Hollow Spheres as an Efficient SeS2 Host for Advanced Li–SeS2 Batteries

“…In the following cycles,HMC@TiN/SeS 2 maintained astable capacity,and delivered capacities of 923, 840, 778, and 690 mAh g À1 in the 10th, 50th, 100th, and 200th cycles,respectively (Figure 4b). [31][32][33] Since polyselenides have similar physicochemical properties and dissolution issues to polysulfides,itis reasonable to speculate that the outer TiNshell can effectively restrict the dissolution of both polyselenides and polysulfides.B esides the strong interaction between TiNand polysulfides,iti sp roposed that highly conductive TiNc ould also accelerate the fragmentation reactions of long-chain polysulfides into shorter chains, [32] which may also benefit the reaction kinetics of the SeS 2 -based cathode. The difference between the two groups convincingly demonstrated the significance of the TiNshell for cycling stability.It was proved by previous studies on LiÀSb atteries that the polar surface of TiNc an chemically adsorb polysulfides through the formation of Ti À Sa nd N À Sb onds.…”

“…[20][21][22][23][24][25][26] However, the study of Se x S y -based materials is still in av ery early stage,a nd the ideas of recent studies are usually limited to the formation of composites of pristine carbonaceous materials with Se x S y ,s o the application potential of the Se x S y cathode has not yet been fully demonstrated. [31][32][33] In this study,w ed esigned and synthesized ah ollow mesoporous carbon@titanium nitride (HMC@TiN) host for loading 70 wt %o fS eS 2 as ac athode material for Li À SeS 2 batteries.H ollow mesoporous carbon can confine ah igh content of SeS 2 within its nanoscale pores and generates an essential electrical contact with the active material;f urthermore,i nner hollow spaces can tolerate the volumetric expansion of SeS 2 during lithiation. [21,26] As inspired by the idea of chemically binding soluble polysulfides to polar substrates in LiÀSbatteries, [27][28][29][30] it is believed that some rationally selected polar materials might also be effective for Se x S y cathodes.A mong various polar substrates applied in Li À Sb atteries,t itanium nitride (TiN) has proved repeatedly to be an excellent Shost that not only ensures excellent electrical conductivity,b ut also efficiently restricts the dissolution of polysulfides into the organic electrolyte.…”

“…[21,26] As inspired by the idea of chemically binding soluble polysulfides to polar substrates in LiÀSbatteries, [27][28][29][30] it is believed that some rationally selected polar materials might also be effective for Se x S y cathodes.A mong various polar substrates applied in Li À Sb atteries,t itanium nitride (TiN) has proved repeatedly to be an excellent Shost that not only ensures excellent electrical conductivity,b ut also efficiently restricts the dissolution of polysulfides into the organic electrolyte. [31][32][33] In this study,w ed esigned and synthesized ah ollow mesoporous carbon@titanium nitride (HMC@TiN) host for loading 70 wt %o fS eS 2 as ac athode material for Li À SeS 2 batteries.H ollow mesoporous carbon can confine ah igh content of SeS 2 within its nanoscale pores and generates an essential electrical contact with the active material;f urthermore,i nner hollow spaces can tolerate the volumetric expansion of SeS 2 during lithiation. TheT iN shell provides ac hemical barrier that retards the diffusion of polysulfides/ polyselenides out of the electrode,t hus promising excellent cycling stability.A sar esult, the HMC@TiN/SeS 2 composite cathode delivers high capacity utilization, good cycling stability,a nd excellent C-rate properties.M oreover,f or areal mass loadings of SeS 2 up to 5mgcm À2 ,t he HMC@TiN/SeS 2 electrode delivered high areal capacities of up to 4mAh cm À2 accompanied by stable cycling life.…”

Hierarchical nitrogen-doped porous graphene/reduced fluorographene/sulfur hybrids for high-performance lithium–sulfur batteries

“…These main obstacles lead tolow active materialutilizations, poor cycling performance and lowcoulombic efficiency. [4][5][6][7][8][9][10][11] To address the aforementioned issues,numerous approaches have been carried out such as mesoporou/microporous carbon, 7, 12 graphene oxide(reduced graphene oxide ) , 4,8,[13][14][15][16] carbon nanotubes, 17 carbon nanofibers, [18][19][20] conductive polymer 21-25 , modified separator [26][27][28][29] , oxides 10, 30-32 and nitrides 9,33 . Among them, carbonbased materialsare usually used as the host of sulfur electrodes due to their high electrical conductivity and chemical stability with goodsulfur loading content.…”

The Use of Spray Drying in Large Batch Synthesis of KB‐S@rGO Composite for High‐Performance Lithium‐Sulfur Batteries

“…More recently, some hetero‐atoms, such as B, N,, S have been doped into the carbon matrix to further improve the interactions between the carbon host and the S species . In the meantime, some polar materials, including the metal oxides (Ti 4 O 7 , TiO 2 , Al 2 O 3 , MnO 2 , SiO 2 ), metal nitride (TiN), metal‐organic frameworks (MOFs) have also been demonstrated that can restrain the polysulfide via chemical interactions. With these efforts, the electrochemical performance of the S cathodes has been greatly improved.…”