Piezoelectric Polarization Optimized Photocharge Separation and Surface Proton Cycling for Efficient Pure Water...

Area of Science:

• Materials Science
• Catalysis
• Renewable Energy

Background:

• Sustainable hydrogen (H₂) and hydrogen peroxide (H₂O₂) production from water is crucial for clean energy.
• Conventional photocatalysts struggle with slow carrier dynamics and inadequate water oxidation capabilities.

Purpose of the Study:

• To develop a high-performance piezo-photocatalyst for efficient water splitting.
• To investigate an intramolecular electron transfer pathway for enhanced photocatalytic activity.

Main Methods:

• Utilized C₃N₅ with cyano and hydroxyl groups to create MCN-8.
• Investigated intramolecular electron transfer and piezoelectric effects.
• Employed in situ infrared spectroscopy to analyze reaction intermediates.

Main Results:

• MCN-8 demonstrated efficient H₂ and H₂O₂ production rates of 4.14 mmol g^-1 h^-1 and 1.39 mmol g^-1 h^-1, respectively.
• Piezoelectric polarization enhanced H⁺ desorption and reaction kinetics.
• Identified key intermediates like ·O₂^- and ·OOH, clarifying the water oxidation mechanism.

Conclusions:

• Surface group modulation in MCN-8 enhances piezo-photocatalytic performance for water splitting.
• This strategy offers a new approach for developing efficient, multifunctional water decomposition catalysts.
• The MCN-8/PVDF-HFP composite film shows promise for practical H₂ and H₂O₂ generation under simulated sunlight.