Emerging trends of g-C3N4-based photocatalysts from 2020 to 2025

The global pursuit of clean energy and environmental remediation has intensified research into solar-driven photocatalysis, with g-C₃N₄ emerging as a leading metal-free polymer semiconductor. Between 2020 and 2025, significant advances have been achieved in overcoming the inherent limitations of pristine g-C₃N₄, such as restricted light absorption, rapid charge recombination, and insufficient active sites, through sophisticated modification strategies. This period has witnessed the refined development of elemental doping, defect engineering, heterostructure construction, and cocatalyst loading, each playing a critical role in enhancing optical properties, charge separation efficiency, and surface reactivity. Contemporary research increasingly focuses on band structure precision engineering, interfacial charge transfer pathways, and defect-mediated catalytic mechanisms. These developments are underpinned by advanced characterization techniques, including X-ray absorption spectroscopy, in-situ Fourier transform infrared spectroscopy, femtosecond transient absorption spectroscopy, Kelvin probe force microscopy, in-situ X-ray photoelectron spectroscopy and electron paramagnetic resonance. Looking forward, emerging trends such as AI-guided material design, atomic-scale defect control, and operando analysis are shaping the next generation of high-efficiency g-C₃N₄ photocatalysts, offering a promising outlook for their application in sustainable energy conversion and environmental remediation.