In this comprehensive study, the synthesis of pure zinc oxide (ZnO) nanoparticles and their molybdenum-doped counterparts (Mo: ZnO) was meticulously carried out through a refined reflux chemical process. The doping concentrations were carefully controlled at 5 and 10% wt%, aiming to investigate the impact on the nanoparticles' properties. A suite of characterization techniques was employed to delve into the structural, morphological, optical, and photocatalytic nuances of the synthesized materials. The crystalline nature and particle size variations were revealed through X-ray diffraction (XRD) analysis, which indicated a discernible decrease in ZnO crystallite size with an increase in Mo doping levels. Scanning electron microscopy (SEM) provided insights into the morphology, displaying a transition from irregular spherical shapes in pure ZnO to a more uniform morphology upon Mo incorporation. Elemental mapping and energy-dispersive X-ray spectroscopy (EDX) analyses corroborated the elemental composition, confirming the integration of Zn, O, and Mo within the samples. Optical properties were probed using UV-Visible spectroscopy, which demonstrated an enhancement in absorption capabilities and modulation of the band gap as a function of Mo doping; the band gap narrowed progressively from 2.9 to 3.14 eV with increasing Mo content from 0 to 10 wt%. Photocatalytic performance was quantitatively assessed, revealing that Mo-doped ZnO nanoparticles exhibited superior activity compared to their undoped counterparts. Notably, the sample with 5% Mo doping achieved an impressive 91% decolorization of dye, signifying a potent photocatalytic effect. This heightened activity was further evidenced by a minimal half-life and a rate constant for the 5 wt% Mo-doped sample that was twice as high as that of pure ZnO, underscoring the significant enhancement brought forth by molybdenum doping.