• Dual-mesoporous heterostructured semiconducting metal oxides were directly fabricated using a simple template-free method, optimizing porosity and improving surface area for enhanced gas-sensing.
• The fabricated sensor exhibited high sensitivity (11.03 for 13 ppm), a rapid response time (21 s), and an impressively low theoretical detection limit (431 ppb) for 2-Undecanone at room temperature.
• An innovative real-time method was developed for analyzing characteristic biomarkers of rice aging, enabling accurate and timely monitoring of rice quality.
• The sensor effectively identifies adulteration in various rice varieties, demonstrating its potential for agricultural food safety inspections.