Tin disulfide(SnS_(2)),due to large interlayer spacing and high theoretical capacity,is regarded as a prospective anode material for lithium-ion batteries.Nevertheless,the poor electron conductivity of SnS_(2) and hug...Tin disulfide(SnS_(2)),due to large interlayer spacing and high theoretical capacity,is regarded as a prospective anode material for lithium-ion batteries.Nevertheless,the poor electron conductivity of SnS_(2) and huge volumetric change during the lithiation/delithiation process lead to a rapid capacity decay of the battery,hindering its commercialization.To address these issues,herein,SnS_(2) is in-situ grown on the surface of carbon nanotubes(CNT)and then encapsulated with a layer of porous amorphous carbon(CNT/SnS_(2)@C)by simple solvothermal and further carbonization treatment.The synergistic effect of CNT and porous carbon layer not only enhances the electrical co nductivity of SnS_(2) but also limits the huge volumetric change to avoid the pulverization and detachment of SnS_(2).Density functional theo ry calculations show that CNT/SnS_(2)@C has high Li^(+)adsorption and lithium storage capacity achieving high reaction kinetics.Consequently,cells with the CNT/SnS_(2)@C anode exhibit a high lithium storage capacity of 837mAh/g after 100 cycles at 0.1 A/g and retaining a capacity of 529.8 mAh/g under 1.0 A/g after 1000 cycles.This study provides a fundamental understanding of the electrochemical processes and beneficial guidance to design high-performance SnS_(2)-based anodes for LIBs.展开更多
Supercapacitors are promising energy storage devices in current century due to their high specific capacitance, cyclic stability, high power density, and high voltage rating. Due to their excellent electrochemical pro...Supercapacitors are promising energy storage devices in current century due to their high specific capacitance, cyclic stability, high power density, and high voltage rating. Due to their excellent electrochemical properties, supercapacitors are invariably used in a multitude of applications ranging from portable electronics to electric vehicles. The electrochemical performance of a supercapacitor mainly depends on the type of electrode-active material used in it. Thereby a careful selection is mandatory to achieve the excellency. Nanostructured electrode-active materials such as carbon nanomaterials, transition metal oxides,transition metal dichalcogenides(TMDs), electronically conducting polymers, etc. are invariably used for supercapacitor application. Among these, TMDs have received great interest, particularly transition metal disulfides such as molybdenum disulfide, tin disulfide(SnS_(2)), etc. Tin is abundant on the earth with excellent charge storage capabilities, attracted great scientific interest for application as electrode materials in supercapacitors. Good electronic conductivity, long cycling life and low-cost are its added advantages.Herein, we discuss the recent trends in layered two-dimensional(2D) SnS_(2)-based electrodes to develop low-cost supercapacitors. Initially, their crystal structure, basic properties, synthesis methods are discussed. Further, strategically designing electrode nanostructures to achieve excellent electrochemical performance is reviewed then after. This includes material design in terms of morphology, pore-size,and shape as well as preparation of 2D SnS_(2)-based nanocomposite electrodes. Furthermore, the challenges and future perspectives of 2D SnS_(2)-based supercapacitors are included.展开更多
Photodetectors based on two-dimensional(2D) materials have attracted considerable attention because of their unique properties. To further improve the performance of self-driven photodetectors based on van der Waals h...Photodetectors based on two-dimensional(2D) materials have attracted considerable attention because of their unique properties. To further improve the performance of self-driven photodetectors based on van der Waals heterojunctions, a conductive band minimum(CBM) matched self-driven SnS_(2)/WS_(2) van der Waals heterojunction photodetector based on a SiO2/Si substrate has been designed. The device exhibits a positive current at zero voltage under 365 nm laser illumination.This is attributed to the built-in electric field at the interface of the SnS_(2) and WS_(2) layer, which will separate and transport the photogenerated carriers, even at zero bias voltage. In addition, the Al_(2)O_(3) layer is covered by the surface of the SnS_(2)/WS_(2) photodetector to further improve the performance, because the Al_(2)O_(3) layer will introduce tensile stress on the surface of the 2D materials leading to a higher electron concentration and smaller effective mass of electrons in the films. This work provides an idea for the research of self-driven photodetectors based on a van der Waals heterogeneous junction.展开更多
Cu_(2)ZnSnS_(4)薄膜因其元素地壳含量丰富、无毒且具有优异的光电性能,受到研究者的广泛关注。本文基于纳米墨水法用Cd部分取代Zn制成了Cu_(2)(Cd x Zn_(1-x))SnS_(4)(CCZTS)薄膜,研究退火时间和后退火温度对薄膜及其太阳电池性能的影...Cu_(2)ZnSnS_(4)薄膜因其元素地壳含量丰富、无毒且具有优异的光电性能,受到研究者的广泛关注。本文基于纳米墨水法用Cd部分取代Zn制成了Cu_(2)(Cd x Zn_(1-x))SnS_(4)(CCZTS)薄膜,研究退火时间和后退火温度对薄膜及其太阳电池性能的影响。研究结果表明,所制备的薄膜为CCZTS相,无其他杂相,薄膜表面平整且致密,结晶性较好。随着退火时间增加,薄膜的晶粒尺寸有所增大,薄膜太阳电池的pn结质量得到提升,其性能也随之提高。通过对薄膜太阳电池进行后退火处理,分析了吸收层的元素扩散对电池性能的影响,在Cd元素形成梯度分布时,电池性能有所提高。随着后退火温度的增加,其电池性能和pn结质量呈现先提高后下降的趋势。经后退火300℃处理后,电池转换效率最佳,为3.13%。展开更多
基金the financial support from the Australian Research CouncilCentre for Materials Science,Queensland University of Technology。
文摘Tin disulfide(SnS_(2)),due to large interlayer spacing and high theoretical capacity,is regarded as a prospective anode material for lithium-ion batteries.Nevertheless,the poor electron conductivity of SnS_(2) and huge volumetric change during the lithiation/delithiation process lead to a rapid capacity decay of the battery,hindering its commercialization.To address these issues,herein,SnS_(2) is in-situ grown on the surface of carbon nanotubes(CNT)and then encapsulated with a layer of porous amorphous carbon(CNT/SnS_(2)@C)by simple solvothermal and further carbonization treatment.The synergistic effect of CNT and porous carbon layer not only enhances the electrical co nductivity of SnS_(2) but also limits the huge volumetric change to avoid the pulverization and detachment of SnS_(2).Density functional theo ry calculations show that CNT/SnS_(2)@C has high Li^(+)adsorption and lithium storage capacity achieving high reaction kinetics.Consequently,cells with the CNT/SnS_(2)@C anode exhibit a high lithium storage capacity of 837mAh/g after 100 cycles at 0.1 A/g and retaining a capacity of 529.8 mAh/g under 1.0 A/g after 1000 cycles.This study provides a fundamental understanding of the electrochemical processes and beneficial guidance to design high-performance SnS_(2)-based anodes for LIBs.
基金Sunway University for supporting this research work under Sunway University Internal Grant Scheme 2022 (grant no. GRTIN-IGS(02)-GAMRG-03-2022)。
文摘Supercapacitors are promising energy storage devices in current century due to their high specific capacitance, cyclic stability, high power density, and high voltage rating. Due to their excellent electrochemical properties, supercapacitors are invariably used in a multitude of applications ranging from portable electronics to electric vehicles. The electrochemical performance of a supercapacitor mainly depends on the type of electrode-active material used in it. Thereby a careful selection is mandatory to achieve the excellency. Nanostructured electrode-active materials such as carbon nanomaterials, transition metal oxides,transition metal dichalcogenides(TMDs), electronically conducting polymers, etc. are invariably used for supercapacitor application. Among these, TMDs have received great interest, particularly transition metal disulfides such as molybdenum disulfide, tin disulfide(SnS_(2)), etc. Tin is abundant on the earth with excellent charge storage capabilities, attracted great scientific interest for application as electrode materials in supercapacitors. Good electronic conductivity, long cycling life and low-cost are its added advantages.Herein, we discuss the recent trends in layered two-dimensional(2D) SnS_(2)-based electrodes to develop low-cost supercapacitors. Initially, their crystal structure, basic properties, synthesis methods are discussed. Further, strategically designing electrode nanostructures to achieve excellent electrochemical performance is reviewed then after. This includes material design in terms of morphology, pore-size,and shape as well as preparation of 2D SnS_(2)-based nanocomposite electrodes. Furthermore, the challenges and future perspectives of 2D SnS_(2)-based supercapacitors are included.
基金Project supported by the National Natural Science Foundation of China (Grant Nos.61974144,62004127,and 12074263)the Science and Technology Foundation of Shenzhen (Grant No.JSGG20191129114216474)the “National” Taipei University of Technology–Shenzhen University Joint Research Program,China (Grant No.2020009)。
文摘Photodetectors based on two-dimensional(2D) materials have attracted considerable attention because of their unique properties. To further improve the performance of self-driven photodetectors based on van der Waals heterojunctions, a conductive band minimum(CBM) matched self-driven SnS_(2)/WS_(2) van der Waals heterojunction photodetector based on a SiO2/Si substrate has been designed. The device exhibits a positive current at zero voltage under 365 nm laser illumination.This is attributed to the built-in electric field at the interface of the SnS_(2) and WS_(2) layer, which will separate and transport the photogenerated carriers, even at zero bias voltage. In addition, the Al_(2)O_(3) layer is covered by the surface of the SnS_(2)/WS_(2) photodetector to further improve the performance, because the Al_(2)O_(3) layer will introduce tensile stress on the surface of the 2D materials leading to a higher electron concentration and smaller effective mass of electrons in the films. This work provides an idea for the research of self-driven photodetectors based on a van der Waals heterogeneous junction.
文摘Cu_(2)ZnSnS_(4)薄膜因其元素地壳含量丰富、无毒且具有优异的光电性能,受到研究者的广泛关注。本文基于纳米墨水法用Cd部分取代Zn制成了Cu_(2)(Cd x Zn_(1-x))SnS_(4)(CCZTS)薄膜,研究退火时间和后退火温度对薄膜及其太阳电池性能的影响。研究结果表明,所制备的薄膜为CCZTS相,无其他杂相,薄膜表面平整且致密,结晶性较好。随着退火时间增加,薄膜的晶粒尺寸有所增大,薄膜太阳电池的pn结质量得到提升,其性能也随之提高。通过对薄膜太阳电池进行后退火处理,分析了吸收层的元素扩散对电池性能的影响,在Cd元素形成梯度分布时,电池性能有所提高。随着后退火温度的增加,其电池性能和pn结质量呈现先提高后下降的趋势。经后退火300℃处理后,电池转换效率最佳,为3.13%。
