Hybrid graphene@MoS₂@TiO₂ microspheres for use as a high performance negative electrode material for lithium ion batteries

Abstract

MoS2 nanosheets were impregnated into mesoporous TiO2 and encapsulated by a graphene layer resulting in excellent Li ion storage properties.

How does Molybdenum Disulfide Store Charge: A Minireview

“…Compositing MoS 2 with some polar materials is an effective strategy to suppress the capacity fading originating from the dissolution of polysulfides. [25,32] The work by Gogotsi and co-workerss uggested that Mo 2 TiC 2 O 2 showed lower binding energy and stronger adsorption for Li 2 St han those of MoS 2 because Li 2 St ended to have a larger bond length and angle on Mo 2 TiC 2 O 2 (Figure 6c). [32] This MoS 2 structure in situ grown on Mo 2 TiC 2 T x enabledt his material to exhibit high capacity and enhanced cycling stability (Figure 6d).…”

“…Pang et al prepared graphene@MoS 2 @TiO 2 througha multi-stepc hemistry strategy. [25] They found TiÀSb onds between MoS 2 and TiO 2 ,w hich suggestedt hat MoS 2 could be well attached to the TiO 2 surface. When used as an anode for LIBs, this electrode delivered ah igh specific capacity of 980 mAh g À1 at 0.1 Ag À1 after 200 cycles (Figure 6e).…”

“…Pang et al. prepared graphene@MoS 2 @TiO 2 through a multi‐step chemistry strategy . They found Ti−S bonds between MoS 2 and TiO 2 , which suggested that MoS 2 could be well attached to the TiO 2 surface.…”

“…The dark-yellow traces on the surfaceo fL if oil ands eparator were due to the shuttling effect of polysulfides in cycled cells (Figure4j-k). [25] Wang et al considered that the interfaces or grain boundaries of Li 2 S x /Mom ight be responsible for capacitive Li + storageg iving rise to an energy storageh igher than the theoretical capacity of MoS 2 (670 mAh g À1 ), similart o metal/ insulatorc omposite thin films and nanosized composites. [13b, 30] Recently,a" graphene nanoreactor" wasf abricated in which Mo clusters generated from the conversion reaction of lithiated 1T MoS 2 could react with Li 2 St of orm MoS 2 owing to the confinemente ffect.…”

“…h) Schematicatomistic modelsofM oS 2 duringl ithiation, i) digital imageso ft he dissolution of polysulfides in diethyl carbonate (DEC)f or cycledL i/MoS 2 cells and Li/S cell (reproducedw ith permission, [20] Copyright American Chemical Society, 2018). SEM images of j) MoS 2 electrodea nd k) graphe-ne@MoS 2 @TiO 2 electrode after1 00 cycles( reproduced with permission, [25] CopyrightR oyal society of chemistry, 2017). Figure 5) of microsized MoS 2 cycled at different voltager anges and found the criticalp oint up to whichM oS 2 could maintain its lamellar structure with enlarged interlayers and provide the highest capacity as well.…”