Layer-structured Shsse attracts much attention as an anode material for potassium storage due to its la rge theoretical capacity.Unfortunately,their practical application is severely restrained by the dramatic volumet...Layer-structured Shsse attracts much attention as an anode material for potassium storage due to its la rge theoretical capacity.Unfortunately,their practical application is severely restrained by the dramatic volumetric variation of SnSSe.Herein,we synthesize ultrafine SnSSe/multilayer graphene nanosheet(SnSSe/MGS) by a vacuum solid-phase reaction and subsequent ball milling.Owing to the strong synergistic effect between the two components,the obtained SnSSe/MGS nanocomposite exhibits a high reversible capacity(423 mAh g^(-1) at 100 mA g^(-1)),excellent rate property(218 mAh g^(-1) at 5 A g^(-1)),and stable cycling performance(271 mAh g^(-1) after 500 cycles at 100 mA g^(-1)) in potassium-ion half batteries.Moreover,the full cell assembled by the SnSSe/MGS anode and the potassiated 3,4,9,10-perylene-tetracar boxylic aciddianhydride cathode shows excellent electrochemical performance between 0.2 and 3.3 V(209 mAh g^(-1) at 50 mA g^(-1) after 100 cycles).The presented two-step synthesis strategy of SnSSe/MGS may also provide ideas to craft other alloy-type anode materials.展开更多
The phonon dispersion and optical properties of mechanically exfoliated SnSSe were investigated with the aid of high-resolution Raman scattering and photoluminescence(PL)spectroscopies along with firstprinciples calcu...The phonon dispersion and optical properties of mechanically exfoliated SnSSe were investigated with the aid of high-resolution Raman scattering and photoluminescence(PL)spectroscopies along with firstprinciples calculations.The Raman modes indicate two-fold symmetry for in-plane vibrations and fourfold symmetry for out-of-plane vibrations.Consequently,the different polarization properties of the phonon modes demonstrate the anisotropic nature of SnSSe.The softening of Raman modes with the increase in temperature is described in terms of thermal expansion and anharmonic scattering,which contributes to phonon vibration,whereas a weak interlayer interaction in the SnSSe layers is observed.The significant suppression of PL signals at a higher temperature is related to the increase in the nonradiative recombination of electron–hole pairs as a result of the increment in the number of phonons and in the thermal excitation of carriers.In addition,the fabricated electrical device on few-layer SnSSe shows a significant ION/IOFF ratio and good electron mobility for optoelectronic applications.These results further improve the understanding of the microscopic details of SnSSe as an important material,providing better insights to control phonon propagation in thermoelectric,photovoltaic,and other materials to induce thermal management.展开更多
基金supported by the National Natural Science Foundation of China (22075147)the Natural Science Foundation of Jiangsu Province of China (BK20180086)。
文摘Layer-structured Shsse attracts much attention as an anode material for potassium storage due to its la rge theoretical capacity.Unfortunately,their practical application is severely restrained by the dramatic volumetric variation of SnSSe.Herein,we synthesize ultrafine SnSSe/multilayer graphene nanosheet(SnSSe/MGS) by a vacuum solid-phase reaction and subsequent ball milling.Owing to the strong synergistic effect between the two components,the obtained SnSSe/MGS nanocomposite exhibits a high reversible capacity(423 mAh g^(-1) at 100 mA g^(-1)),excellent rate property(218 mAh g^(-1) at 5 A g^(-1)),and stable cycling performance(271 mAh g^(-1) after 500 cycles at 100 mA g^(-1)) in potassium-ion half batteries.Moreover,the full cell assembled by the SnSSe/MGS anode and the potassiated 3,4,9,10-perylene-tetracar boxylic aciddianhydride cathode shows excellent electrochemical performance between 0.2 and 3.3 V(209 mAh g^(-1) at 50 mA g^(-1) after 100 cycles).The presented two-step synthesis strategy of SnSSe/MGS may also provide ideas to craft other alloy-type anode materials.
基金supported by the National Key R&D Program of China(2018YFC0910602)the National Natural Science Foundation of China(61775145/61525503/61620106016)+4 种基金Project of the Department of Education of Guangdong Province(2016KCXTD007)Shenzhen Basic Research Project(JCYJ20190808123401666/GJHZ20190822095420249/JCYJ20170412110212234)M.R.M.acknowledges Narodowe Centrum Nauki,Poland(2018/31/B/ST3/02111)M.I.acknowledge Scientific Research at King Khalid University,Saudi Arabia(R.G.P.21/318/42)Z.M.acknowledge Beihang Hefei Innovation Research Institute China(BHKX-19-02).
文摘The phonon dispersion and optical properties of mechanically exfoliated SnSSe were investigated with the aid of high-resolution Raman scattering and photoluminescence(PL)spectroscopies along with firstprinciples calculations.The Raman modes indicate two-fold symmetry for in-plane vibrations and fourfold symmetry for out-of-plane vibrations.Consequently,the different polarization properties of the phonon modes demonstrate the anisotropic nature of SnSSe.The softening of Raman modes with the increase in temperature is described in terms of thermal expansion and anharmonic scattering,which contributes to phonon vibration,whereas a weak interlayer interaction in the SnSSe layers is observed.The significant suppression of PL signals at a higher temperature is related to the increase in the nonradiative recombination of electron–hole pairs as a result of the increment in the number of phonons and in the thermal excitation of carriers.In addition,the fabricated electrical device on few-layer SnSSe shows a significant ION/IOFF ratio and good electron mobility for optoelectronic applications.These results further improve the understanding of the microscopic details of SnSSe as an important material,providing better insights to control phonon propagation in thermoelectric,photovoltaic,and other materials to induce thermal management.
