Abstract
Promoting interfacial reaction kinetics is highly desirable for achieving high-performances of anode ma-terial in alkali-ion batteries.Herein,flower-like MoSe2/MoO3-x@rGO composites are fabricated by a facile solvothermal method involving a thermal-treatment at 800℃.When evaluated as an anode material for potassium ion batteries,MoSe2/MoO3-x@rGO delivers 248.2 mA h g-1 after 50 cycles at 0.2 A g-1 with a capacity retention of 84.6％and 182.9 mA h g 1 after 150 cycles at 1.0 A g-1 with a capacity retention of almost 61.2％,superior to those of bare MoSe2 or MoSe2@rGO composites.Analysis from electrochemical measurements,the amorphous MoO3-x containing oxygen vacancies could not only effectively buffer the self-aggregation of MoSe2 nanosheets but also provides lots of accessible active sites for potassium ion storage.Additionally,the open channels in the amorphous MoO3-x phase lead to easier ion hopping and smaller diffusion barriers.Furthermore,the built-in electric field at the interface would be beneficial for electron transfer and K-ion migration across the hetero-junction interface.Moreover,larger dielectric po-larization induced by the high relative permittivity of amorphous MoO3-x would reduce charge transfer resistance and enhance K-ion migration across electric double-layer.Our work provides new insight into the enhanced performance of anode material coated by an amorphous layer with large relative permit-tivity.
基金项目
Natural Science Foundations of China(12174057)
Natural Science Foundations of China(22179020)
Natural Science Foundation of Fuccccjian Province(2021L3011)
Fujian Natural Science Foundation for Distinguished Young Scholars(2020J06042)
NETL
NSTL
万方数据