The “Smart Air Quality Monitoring and Purification System using ESP32” is designed to provide a low-cost, real-time solution for monitoring and improving air quality. Utilizing the ESP32 microcontroller along with MQ135 and MQ7 gas sensors and a DHT11 temperature and humidity sensor, the system continuously measures indoor air conditions. Real-time data is displayed on an OLED screen, while LED indicators classify air quality as good, moderate, or poor. In the case of poor air quality, a relay-controlled fan is activated automatically to purify the air, and visual alerts are provided to users. The system offers an affordable and easily implementable approach for smart homes, offices, and industrial environments, with potential for IoT integration, mobile app connectivity, and cloud-based data logging in the future.
Sherekar et al. (Sat,) studied this question.