CuS-Cobalt Porphyrin Organic-Inorganic Heterojunction with a Long-Lived Charge-Separated State for Efficient...

Area of Science:

• Materials Science
• Photocatalysis
• Renewable Energy

Background:

• Selective carbon dioxide (CO2) reduction using infrared (IR) light is hindered by slow reaction rates and inefficient charge carrier behavior.
• Developing advanced photocatalysts is crucial for efficient solar-to-fuel energy conversion.

Purpose of the Study:

• To design and synthesize a novel organic-inorganic hybrid heterojunction for enhanced IR-driven CO2 reduction.
• To investigate the underlying mechanisms responsible for improved catalytic performance.

Main Methods:

• Fabrication of a heterojunction using HKUST-1-derived CuS and cobalt porphyrin (CoTPPS).
• Characterization using femtosecond transient absorption spectroscopy and synchrotron radiation measurements.
• Computational analysis using Density Functional Theory (DFT) calculations.

Main Results:

• Achieved exceptional methane (CH4) generation rate (178.02 µmol g⁻¹ h⁻¹) with 96.5% CH4 selectivity under IR irradiation.
• Demonstrated a 170-fold increase in carrier lifetimes due to strong interfacial electronic coupling and an internal electric field.
• DFT calculations revealed a reduced *COOH formation barrier (1.43 to 1.07 eV) and stabilization of the *CHO intermediate.

Conclusions:

• The synergistic effect between the MOF-derived scaffold and molecular active sites enables precise regulation of reaction intermediates.
• This hybrid material presents a versatile platform for designing highly efficient IR-responsive photocatalysts for solar fuel production.
• The study advances rational design principles for hybrid materials in photocatalytic CO2 conversion.