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 Zr 4+ 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.