<p>Recent advancements in science and technology have revolutionized day-to-day life and provided numerous benefits but also posed potential risks, particularly in environmental settings. One of the most important concerns is the growing environmental pollution, a byproduct of industrialization and population extension. The release of harmful gases and non-biodegradable dyes is rapidly escalating, endangering ecosystems and public health. All condemn pollution control strategies, and chemical sensors play a pivotal role in detecting and mitigating toxic substances. The chemiresistive sensors are particularly noteworthy for their widespread use in real-time implementation due to their excellent sensitivity, selectivity, compact device, and ease of fabrication. Metal oxide semiconductors (MOS), including zinc oxide (ZnO), tin oxide (SnO₂), and tungsten oxide (WO₃), are frequently employed for gas sensing due to their high sensitivity and adaptability. The effectiveness of MOS-based sensors can be enhanced by altering factors like crystal structure, synthesis methods, dopants, and temperature. Gas sensors based on MOS technology at room temperature are integral in diverse sectors such as environmental monitoring, healthcare diagnostics, and industrial safety. Understanding the factors that influence gas sensor performance, such as grain size, temperature, and material morphology, is essential for developing more efficient, selective, and reliable sensors.</p>