Abstract

Photocatalyst-assisted artificial photosynthesis has been widely recognized as a promising approach for environmental treatment. In this work, a novel hydrothermal technique was employed to synthesize three-dimensional (3D) SrTiO₃, which was then combined with two-dimensional (2D) g-C₃N₄ via a self-assembly process to create a 2D/3D g-C₃N₄/SrTiO₃ heterojunction. The morphological characteristics and optical features of the fabricated photocatalysts were assessed using powder XRD, SEM, TEM, and UV-DRS spectroscopy. The photocatalytic activity of the obtained specimens was evaluated by monitoring the photodecomposition of methylene blue (MB), a persistent organic dye pollutant commonly found in wastewater, under visible light. The results demonstrated that the binary g-C₃N₄/SrTiO₃ hybrid semiconductor exhibited excellent photocatalytic behavior, achieving a degradation efficiency of 72% after 60 min with reaction kinetics (0.018 min⁻¹), which was nearly 1.3 and 66.25 times higher than that of g-C₃N₄ and SrTiO₃, respectively. This enhancement is ascribed to the effective creation of heterojunctions between g-C₃N₄ and SrTiO₃, which facilitate improved charge separation and transfer, thereby promoting the degradation efficiency of organic pollutants. Additionally, the photocatalyst demonstrated excellent stability and reusability over four successive cycles. Based on experimental observations, a plausible photocatalytic mechanism was proposed. These findings provide a promising route for designing efficient and durable photocatalytic materials for environmental applications.