TY  - JOUR
AU  - Yang, Su
AU  - Wang, Meiling
AU  - Zhang, Yong
AU  - He, Pinyi
AU  - Cong, Wenhua
AU  - Wang, Chongji
AU  - Yang, Qiankun
AU  - Liu, Xuguang
AU  - Wang, Tian
AU  - Zhang, Xianming
AU  - Zhou, Jiadong
PY  - 2023
TI  - Single-Molecule Confinement Induced Intrinsic Multi-Electron Redox-Activity to Enhance Supercapacitor Performance
JO  - Energy & Environmental Materials
SN  - 2575-0348
VL  - 6
IS  - 4
AB  - Aggregation of polyoxometalates (POM) is largely responsible for the reduced performance of POM-based energy-storage systems. To address this challenge, here, the precise confinement of single Keggin-type POM molecule in a porous carbon (PC) of unimodal super-micropore (micro-PC) is realized. Such precise single-molecule confinement enables sufficient activity center exposure and maximum electron-transfer from micro-PC to POM, which well stabilizes the electron-accepting molecules and thoroughly activates its inherent multi-electron redox-activity. In particular, the redox-activities and electron-accepting properties of the confined POM molecule are revealed to be super-micropore pore size-dependent by experiment and spectroscopy as well as theoretical calculation. Meanwhile, the molecularly dispersed POM molecules confined steadily in the "cage" of micro-PC exhibit unprecedented large-negative-potential stability and multiple-peak redox-activity at an ultra-low loading of ~11.4 wt%. As a result, the fabricated solid-state supercapacitor achieves a remarkable areal capacitance, ultrahigh energy and power density of 443 mF cm−2, 0.12 mWh cm−2 and 21.1 mW cm−2, respectively. This work establishes a novel strategy for the precise confinement of single POM molecule, providing a versatile approach to inducing the intrinsic activity of POMs for advanced energy-storage systems.
UR  - https://doi.org/10.1002/eem2.12396
DO  - 10.1002/eem2.12396