An iron based organic framework coated with nickel hydroxide for energy storage, conversion and detection

Area of Science:

• Electrochemistry
• Materials Science
• Nanotechnology

Background:

• Metal-organic frameworks (MOFs) show promise for electrochemical applications but suffer from poor conductivity.
• Developing MOF-based electrode materials with enhanced electrical conductivity is crucial for advancing electrochemical devices.

Purpose of the Study:

• To engineer a conductive composite material by modifying Fe-MOF with Ni(OH)2.
• To evaluate the performance of the Fe-MOF@Ni(OH)2 composite in supercapacitors, oxygen evolution reactions (OER), and electrochemical sensing.

Main Methods:

• Constructing a conductive circuit by growing a hydroxide layer on Fe-MOF.
• Synthesizing the Fe-MOF@Ni(OH)2 composite material.
• Characterizing the material's electrochemical properties using techniques relevant to supercapacitors, OER, and sensing.

Main Results:

• The Fe-MOF@Ni(OH)2 composite demonstrated improved electrical conductivity compared to bare Fe-MOF.
• Supercapacitor performance: specific capacity of 188 mAh g⁻¹ at 1 A g⁻¹ and energy density of 67.1 Wh kg⁻¹ for an asymmetric device.
• Oxygen evolution reaction (OER): low overpotential of 280 mV at 10 mA cm⁻² and a Tafel slope of 37.6 mV dec⁻¹.
• Electrochemical sensing: a detection limit of 5 μM for Bisphenol A (BPA).

Conclusions:

• The Fe-MOF@Ni(OH)2 composite effectively overcomes the conductivity limitations of MOFs.
• The material exhibits multifunctional capabilities, showing excellent performance in supercapacitors, OER, and electrochemical sensing.
• This study offers valuable insights for designing advanced MOF-based electrode materials for diverse electrochemical applications.