MOF-derived molybdenum selenide on Ti3C2Tx with superior capacitive performance for lithium-ion capacitors

Two-dimensional Ti 3 C 2 T x exhibits outstanding rate property and cycle performance in lithium-ion capacitors (LICs) due to its unique layered structure, excellent electronic conductivity, and high specific surface area. However, like graphene, Ti 3 C 2 T x restacks during electrochemical cycling due to hydrogen bonding or van der Waals forces, leading to a decrease in the specific surface area and an increase in the diffusion distance of electrolyte ions between the interlayer of the material. Here, a transition metal selenide MoSe 2 with a special three-stacked atomic layered structure, derived from metal—organic framework (MOF), is introduced into the Ti 3 C 2 T x structure through a solvo-thermal method. The synergic effects of rapid Li + diffusion and pillaring effect from the MoSe 2 and excellent conductivity from the Ti 3 C 2 T x sheets endow the material with excellent electrochemical reaction kinetics and capacity. The composite Ti 3 C 2 T x @MoSe 2 material exhibits a high capacity over 300 mAh·g −1 at 150 mA·g −1 and excellent rate property with a specific capacity of 150 mAh·g −1 at 1500 mA·g −1 . Additionally, the material shows a superior capacitive contribution of 86.0% at 2.0 mV·s −1 due to the fast electrochemical reactions. A Ti 3 C 2 T x @MoSe 2 //AC LIC device is also fabricated and exhibits stable cycle performance.