In this study, a robust hybrid heterojunction composite of g-C3N4/ZnO was successfully synthesized using a straightforward and cost-effective coprecipitation method. The resulting composite amalgamates the properties of graphitic carbon nitride (g-C3N4) and zinc oxide nanoparticles (ZnO NPs). Thorough characterization using techniques such as XRD, FT-IR, FESEM, HR-TEM, UV-DRS, and EDX confirmed the structural and elemental composition of the catalyst. The challenge of using photons as the sole energy source for the activation of photocatalysts under ambient conditions was addressed. The photocatalytic potential of the hybrid heterojunctions was assessed by degrading the methyl orange (MO) dye under sunlight. The g-C3N4/ZnO composite exhibited effective suppression of charge recombination during photocatalytic degradation. Notably, the heterojunction g-C3N4/ZnO composite displayed remarkable photocatalytic performance, achieving a substantial 98 % degradation of MO within a mere 90 min of solar irradiation, outperforming other materials. Moreover, the synthesized composites exhibited favorable attributes in terms of recyclability and mechanical stability, retaining their efficacy over five cycles. This substantiates their promising role as potential candidates for future photocatalyst applications. In essence, hybrid g-C3N4/ZnO heterojunction composites offer a robust solution for efficient and sustainable photocatalytic degradation of organic pollutants.