Cu₉S₅/Gel-Derived TiO₂ Composites for Efficient CO₂ Adsorption and Conversion

Area of Science:

• Materials Science
• Catalysis
• Environmental Science

Background:

• Photocatalytic systems require efficient CO₂ adsorption and conversion.
• Gel composites offer a promising strategy for enhancing these processes.

Purpose of the Study:

• To synthesize and characterize Cu₉S₅/TiO₂ gel composites for photocatalytic CO₂ reduction.
• To investigate the role of hydrazine hydrate in enhancing material performance.

Main Methods:

• Microwave-assisted sol-gel process for TiO₂.
• Hydrazine-hydrate-assisted hydrothermal synthesis of Cu₉S₅/TiO₂ gel composites.
• Characterization using XRD, TEM, XPS, and DFT calculations.

Main Results:

• The optimized 0.36Cu₉S₅/TiO₂ composite showed high methane production (34 μmol·g^-1·h^-1) and selectivity (64.76% CH₄).
• Hydrazine hydrate facilitated phase transformation and improved interfacial electronic properties.
• DFT calculations confirmed reduced energy barriers for CO₂ conversion intermediates.

Conclusions:

• Gel-derived Cu₉S₅/TiO₂ composites effectively couple CO₂ adsorption with selective photocatalytic reduction.
• This strategy offers new design principles for adsorption-conversion hybrid materials.