High-Performance Lithium-Ion Capacitors Based on Porosity-Regulated Zirconium Metal-Organic Frameworks

Comprised of a battery anode and a supercapacitor cathode, hybrid lithium-ion capacitors (HLICs) are found to be an effective solution to realize both high power density and high energy density at the same time. Organic-inorganic hybrid materials with well-organized framework guided by the reticular chemistry are one of the promising anode materials for HLICs because of rich active sites and ordered porosity. Herein, metal-organic framework consisting of Zr4+ metal ions and tetrathiafulvalene-based ligands (Zr-MOF) is proposed as the pseudocapacitive anode of HLICs. The Zr-MOF possesses high stability, high crystallinity, and multiple meso-microporous channels favorable for ion transport. The as-prepared Zr-MOF||activated carbon HLICs present high energy density (122.5 Wh kg(-1)), high power density (12.5 kW kg(-1)), and stable cycling performance (86% capacity retention after 1000 cycles at 2000 mA g(-1)) within the operating voltage range of 1.0-4.0 V. The results expand the direct application of MOF for bridging the performance gap between batteries and supercapacitors.

Automated summary

Hybrid lithium-ion capacitors (HLICs) with a battery anode and a supercapacitor cathode offer high energy density and power density. Organic-inorganic hybrid materials guided by reticular chemistry and Zr-MOF, consisting of Zr4+ metal ions and tetrathiafulvalene-based ligands, show promise as anode materials for HLICs. Zr-MOF || activated carbon HLICs exhibit outstanding performance within the operating voltage range.