Porous-tube arrays with electron-correlated strong synergy of sulfide/ phosphide heterostructures for ultrahigh-capacity and stable battery

This study reports a significant advance toward the multicomponent design and fabrication of novel hierarchical porous-tube array electrodes by engineering surfaces and interfaces of different active materials. The hierarchical electrodes with an electron-correlated strong synergy of traditional bimetallic sulfide/phosphide heterostructures were achieved by controlled ion-exchange processes. Each submicron-sized tube has a porous shell consisting of Fe 7 (PO 4 ) 6 inner layer with metalloid-like electrical conductivity wrapped by interlaced ultrathin CoS nanoflakes, which provides both a stable nano-micron architecture and highly active heterostructure interfaces. The CoS/Fe 7 (PO 4 ) 6 heterostructure electrode showed an ultrahigh specific capacity reaching up to 461.5mAh·g -1 at 5 mA·cm -2 , much higher than that of a single component and previously reported multicomponent ones. Particularly, the electrode also showed remarkable stability with capacity retention of 92.0% after 10,000 charge-discharge cycles at a high current density of 30 mA·cm -2 . The practical application demonstrated that two connected devices in a series can power 16 LEDs. This work provides an effective pathway to hierarchical heterostructure arrays for energy storage devices with high energy density, fast recharging ability, and long cycle life. • For the first time porous-tube array electrodes with nano/micron bimetallic sulfide /phosphide heterostructures for strong electron-correlated synergy were achieved. • The electrode has an ultrahigh capacity reaching 461.5mAh·g -1 at 5 mA·cm -2 and remarkable stability with 92.0% capacity retention after 10,000 cycles at 30 mA·cm -2 . • The solid-state asymmetric battery delivered a higher energy density of 82 Wh·kg -1 (at 750 W·kg -1 ) and also showed fast recharging ability and long cycle life.