Emerging g-C3N4-Based Piezo-Photocatalysis: Synergistic Mechanisms, Modification Strategies, and Applications

• • Heterojunction construction with piezoelectric materials (e.g., CeO2/g-C3N4/PVDF) enhances charge separation, achieving a degradation rate of 0.023 min−1 for organic pollutants, a 2.3-fold improvement over pristine g-C3N4, critical for industrial wastewater treatment. • • Morphology engineering, such as porous nanosheets, increases surface area to 89 m2/g, boosting H2 evolution to 1234 μmol h−1 g−1 under visible light, a 4.5-fold enhancement, relevant for scalable solar fuel production. • • Element doping (e.g., phosphorus) extends visible-light absorption to 550 nm and reduces charge transfer resistance by 40%, improving photocurrent density to 0.85 mA cm−2, essential for efficient photoelectrochemical cells. • • In-situ characterizations reveal that strain-induced polarization shifts the d-band center by 0.3 eV, enhancing CO2 adsorption and photoreduction to CH4 with a selectivity of 92%, offering a route for carbon-neutral fuel synthesis.