<p>The growth of large-area, continuous, and crystalline vertically grown MoS₂ nanostructures is always highly challenging. Morphological tuning of atmospheric pressure chemical vapor deposition (APCVD)-grown MoS₂ nanostructures can be achieved via precise control over deposition parameters, demonstrating engineered properties suitable for gas sensing applications. In the present work, a one-step APCVD growth procedure is developed for optimized morphological evolution, which allows the synthesis of large-scale cross-linked vertically grown MoS₂ nanopetal structures with high crystallinity and phase selectivity. The optimized morphological tuning enabled the transformation from MoO₂/MoS₂ nanoplates into hybrid MoO₂/MoS₂ nanostructures, leading to the growth of V-MoS₂ nanopetals over a SiO₂/Si substrate by controlling sulfur concentration with the help of sulfur precursor temperature and Ar gas flow. Field-emission scanning electron microscopy (FESEM) clearly shows the evolution of the morphology in APCVD growth. Raman spectra and x-ray diffraction clearly support the synthesis of vertically grown cross-linked MoS₂ nanopetals and structural and phase transformation from MoO₂/MoS₂ nanoplates to V-MoS₂ nanopetals. Current–voltage (<i>I</i>–<i>V</i>) characteristics demonstrate an increase in current conduction as the morphology changes from MoO₂/MoS₂ nanoplates to V-MoS₂ nanopetals and shows ohmic behavior. The edge-enriched V-MoS₂ nanopetals demonstrate the highest sensitivity of 61.78% for 100&#xa0;ppm NO₂ at 100°C operating temperature. The relative response of the V-MoS₂ nanopetal sensor increases from 16.93% to 61.78% as the gas concentrations of NO₂ increases from 1&#xa0;ppm to 100&#xa0;ppm at 100°C operating temperature. This optimized nanosensor demonstrates the highest selectivity towards NO₂ gas, with a limit of detection (LOD) of 1&#xa0;ppm and a fast response of 22&#xa0;s.</p>