학술논문

Discovery of a three-proton insertion mechanism in α-molybdenum trioxide leading to enhanced charge storage capacity
Document Type
Original Paper
Source
Nature Communications. 14(1)
Subject
Language
English
ISSN
2041-1723
Abstract
The α-molybdenum trioxide has attracted much attention for proton storage owing to its easily modified bilayer structure, fast proton insertion kinetics, and high theoretical specific capacity. However, the fundamental science of the proton insertion mechanism in α-molybdenum trioxide has not been fully understood. Herein, we uncover a three-proton intercalation mechanism in α-molybdenum trioxide using a specially designed phosphoric acid based liquid crystalline electrolyte. The semiconductor-to-metal transition behavior and the expansion of the lattice interlayers of α-molybdenum trioxide after trapping one mole of protons are verified experimentally and theoretically. Further investigation of the morphology of α-molybdenum trioxide indicates its fracture behavior upon the proton intercalation process, which creates diffusion channels for hydronium ions. Notably, the observation of an additional redox behavior at low potential endows α-molybdenum trioxide with an improved specific discharge capacity of 362 mAh g−1.
The proton insertion mechanism in α-molybdenum trioxide remains incompletely elucidated. Herein, the authors uncover a three-proton intercalation mechanism within α-molybdenum trioxide using a specially designed electrolyte, which endows α-molybdenum trioxide with an improved specific discharge capacity.