Reconciling Mass Loading and Gravimetric Performance of MnO_2 Cathodes by 3D-Printed Carbon Structures for Zinc-Ion Batteries

摘要

To promote the real application of zinc-ion batteries (ZIBs), reconciling thehigh mass loading and gravimetric performance of MnO_2 electrodes is ofparamount importance. Herein, the rational regulation of 3D-printed carbonmicrolattices (3DP CMs) enabling an ultrathick MnO_2 electrode with wellmaintainedgravimetric capacities is demonstrated. The 3DP CMs madeof graphene and carbon nanotubes (CNTs) are fabricated by direct ink 3Dprinting and subsequent high-temperature annealing. 3D printing enablesa periodic structure of 3DP CMs, while the thermal annealing contributesto high conductivity and defective surfaces. Due to these structural merits,uniform electrical field distribution and facilitated MnO_2 deposition over the3DP CMs are permitted. The optimal electrode with MnO_2 loaded on the3DP CMs can achieve a record-high specific capacity of 282.8 mAh g?1 evenat a high mass loading of 28.4 mg cm?2 and high ion transfer dynamics,which reconciles the loading mass and gravimetric performance. As a result,the aqueous ZIBs based on the 3DP CMs loaded MnO_2 afford an outstandingperformance superior to most of the previous reports. This studyreveals the essential role of interaction between active materials and currentcollectors, providing an alternative strategy for designing high-performanceenergy storage devices.