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Title: High-performance organic pseudocapacitors via molecular contortion
Pseudocapacitors harness unique charge-storage mechanisms to enable high-capacity, rapidly cycling devices. Here we describe an organic system composed of perylene diimide and hexaazatrinaphthylene exhibiting a specific capacitance of 689 F g−1 at a rate of 0.5 A g−1, stability over 50,000 cycles, and unprecedented performance at rates as high as 75 A g−1. We incorporate the material into two-electrode devices for a practical demonstration of its potential in next-generation energy-storage systems. We identify the source of this exceptionally high rate charge storage as surface-mediated pseudocapacitance, through a combination of spectroscopic, computational and electrochemical measurements. By underscoring the importance of molecular contortion and complementary electronic attributes in the selection of molecular components, these results provide a general strategy for the creation of organic high-performance energy-storage materials.  more » « less
Award ID(s):
2002634
PAR ID:
10231013
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Nature Materials
ISSN:
1476-1122
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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