MOF Template-Derived Carbon Shell-Embedded CoP Hierarchical Nanosheet as Bifunctional Catalyst for Overall Water...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Efficient electrocatalysts are vital for sustainable hydrogen production via overall water splitting.
• Developing earth-abundant, highly active bifunctional catalysts for hydrogen evolution (HER) and oxygen evolution (OER) remains a challenge.

Purpose of the Study:

• To design and synthesize novel earth-abundant bifunctional electrocatalysts for efficient overall water splitting.
• To investigate the structure-property relationships of CoP-based nanostructures derived from Zeolitic Imidazolate Framework-67 (ZIF-67).

Main Methods:

• Fabrication of vertically oriented CoP hierarchical nanosheet arrays with in situ-assembled carbon skeletons on Ti foil using a ZIF-67 template.
• Electrochemical characterization of the catalyst for HER and OER performance, including overpotential and Tafel slope measurements.
• Assembly and testing of a C@CoP||C@CoP electrolyzer for overall water splitting performance and durability.

Main Results:

• The ZIF-67 derived hierarchical nanosheet architecture significantly enhanced electrical conductivity and active site exposure.
• The bifunctional hybrid catalyst demonstrated low overpotentials of 72 mV for HER and 329 mV for OER at 10 mA cm^-2.
• The assembled electrolyzer achieved efficient overall water splitting at 1.63 V with superior durability.

Conclusions:

• The developed CoP-based hierarchical nanostructures, templated by ZIF-67, show excellent bifunctional electrocatalytic activity for water splitting.
• This work presents a promising structure engineering strategy for MOF-derived hybrids for advanced energy applications.
• The findings highlight the potential of earth-abundant materials for sustainable hydrogen production.