Unveiling the Defect-Accelerated Charge Transfer Mechanism in ZnIn₂S₄/g-C₃N₄ Z-Scheme Heterojunctions for Efficient Solar Fuel Production

Abstract

Design and fabrication of efficient Z-scheme heterojunctions are critical for advancing solar fuel production, yet constructing directed interfacial charge transfer pathways remains challenging. Herein, we report ZnIn₂S₄/g-C₃N₄ Z-scheme heterojunctions where interfacial defects serve as electron highways for rapid charge separation. These heterostructures exhibit a significant enhancement in CO₂ photoreduction efficiency compared to pristine components, while maintaining > 90% activity after three cycles. Experimental and theoretical analyses confirm that interfacial defects act as charge-transfer mediators, synergistically accelerating surface redox kinetics to enable efficient solar fuel production (232.92 μmol g^-1 of CO and 10.7 mmol g^-1 of H₂ after 5 h of illumination). This work establishes interfacial defect utilization as an efficient strategy for high-performance Z-scheme systems in value-added chemical synthesis.

Keywords

interfacial charge transfer mechanism / interfacial defects / solar fuel production / surface redox kinetics / Z-scheme heterojunction

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2026 The Author(s). Carbon Neutralization published by Wenzhou University and John Wiley & Sons Australia, Ltd.