By Introducing Multiple Hydrogen Bonds Endows MOF Electrodes with an Enhanced Structural Stability

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Metal-organic frameworks (MOFs) show promise for energy storage but suffer from poor structural stability due to weak coordination bonds.
• Enhancing the intrinsic stability of MOFs is crucial for their practical application in energy storage devices.

Purpose of the Study:

• To improve the structural stability and introduce self-healing capabilities in MOFs for energy storage applications.
• To investigate the effect of quadruple hydrogen bonds on MOF stability and performance.

Main Methods:

• Incorporation of quadruple hydrogen bonds into MOF structures to create cross-linked networks.
• Fabrication of a self-healing hybrid material (SHH-Cu-MOF@Ti3C2Tx) and a control material (H-Cu-MOF@Ti3C2Tx).
• Assembly of an asymmetric supercapacitor (ASC) using the SHH-Cu-MOF@Ti3C2Tx and activated carbon (AC) electrodes.

Main Results:

• The SHH-Cu-MOF@Ti3C2Tx demonstrated superior capacitance retention (89.4% after 5000 cycles) compared to the control (79.9%).
• The dynamic hydrogen bonds provided self-healing ability and protected the MOF structure under stress.
• The fabricated ASC achieved a specific capacitance of 47.4 F g-1 at 1 A g-1, with an energy density of 16.9 Wh kg-1 and power density of 800 W kg-1.

Conclusions:

• Quadruple hydrogen bonds significantly enhance the structural stability and cycling performance of MOFs for energy storage.
• The self-healing hybrid material shows potential for developing durable and high-performance supercapacitors.
• The developed asymmetric supercapacitor exhibits promising energy and power density characteristics.