Hollow Cu_2-xS@NiFe Layered Double Hydroxide Core-Shell S-Scheme Heterojunctions with Broad-Spectrum Response and...

Area of Science:

• Materials Science
• Photocatalysis
• Nanotechnology

Background:

• Designing heterojunctions is crucial for improving photocatalyst efficiency by enhancing charge separation.
• Metal sulfide/layered double hydroxide (LDH) composites show promise in photocatalysis.

Purpose of the Study:

• To synthesize and characterize Cu2-xS@NiFe-LDH hollow nanoboxes with a core-shell structure.
• To investigate the photocatalytic performance and stability of the novel heterojunction for hydrogen production and pollutant degradation.
• To elucidate the charge transfer mechanism within the heterojunction.

Main Methods:

• Synthesis of Cu2-xS@NiFe-LDH hollow nanoboxes.
• Characterization using techniques like in situ X-ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR).
• Evaluation of photocatalytic activity through hydrogen production and tetracycline degradation experiments.
• Analysis of carrier dynamics using transient photoluminescence spectra (TRPL).

Main Results:

• The Cu2-xS@NiFe-LDH hollow nanoboxes demonstrated broad-spectrum response, good photothermal, and photocatalytic activity.
• The unique hollow structure and core-shell S-scheme heterojunction significantly enhanced photocatalytic activity and stability.
• Achieved high photocatalytic hydrogen production efficiency (5176.93 µmol h⁻¹ g⁻¹) and tetracycline degradation (98.3%), outperforming pure Cu2-xS and NiFe-LDH.
• TRPL spectra indicated prolonged carrier lifetime, and XPS/ESR confirmed an S-scheme electron transfer pathway.

Conclusions:

• The S-scheme heterojunction in Cu2-xS@NiFe-LDH hollow nanoboxes facilitates efficient charge separation and strong photoredox capabilities.
• This engineered nanostructure significantly boosts photocatalytic performance for hydrogen production and environmental remediation.
• The study highlights the potential of designing S-scheme heterojunctions for advanced photocatalytic applications.