Halogen-Tuned BiOI-Cl Solid Solutions with Enhanced Built-In Electric Field for Superior Piezo-Photocatalytic...

Area of Science:

• Materials Science
• Environmental Chemistry
• Catalysis

Background:

• Piezo-photocatalysis offers a promising avenue for environmental remediation by utilizing both mechanical and light energy.
• Understanding the interplay between material properties and catalytic activity is crucial for developing efficient environmental purification technologies.

Purpose of the Study:

• To investigate the piezo-photocatalytic performance of BiOI_(1-x)Cl_x solid solutions.
• To elucidate the role of built-in electric field regulation in charge carrier dynamics.
• To explore the potential of multifield coupled catalysis for environmental remediation.

Main Methods:

• Synthesis and characterization of BiOI_(1-x)Cl_x solid solutions.
• Evaluation of piezoelectricity, optical absorption, and charge separation efficiency.
• Degradation experiments using rhodamine B (RhB) as a model pollutant under simulated solar light and mechanical stress.

Main Results:

• Halogen substitution in BiOI_(1-x)Cl_x effectively modulates piezoelectricity, optical absorption, and charge separation.
• The BiOI_0.25Cl_0.75 solid solution achieved 99.9% RhB degradation in 16 min.
• The degradation rate constant for BiOI_0.25Cl_0.75 was significantly higher than individual piezocatalysis or photocatalysis, attributed to synergistic effects.

Conclusions:

• BiOI_0.25Cl_0.75 solid solutions exhibit superior piezo-photocatalytic activity due to synergistic effects of band structure tuning and amplified piezoelectric fields.
• This material demonstrates efficient charge transfer and suppressed recombination, leading to enhanced pollutant degradation.
• Piezo-photocatalysis presents a sustainable strategy for environmental purification by harnessing combined solar and mechanical energy.