Enhancing Particulate Matter and Airborne Microorganisms Removals using Indoor Plants with Electrical Ground Connection

A method for particulate matter and airborne microorganisms removals using indoor plants with electrical ground connection was investigated. The electrochemically activated plants through electrical grounding were used as the basis of air purification system. In this study, a novel concept of plants-based indoor air purification system was examined in the presence of electrical ground connection. <i>Epipremnum aureum</i> was selected as a primary experimental plant. The cultivation pots with an electrode were connected to earth point via a wire. Experiments were conducted in a system where the pots were placed, with various concentrations of particulate matter and airborne microorganisms were applied to analyze removal rates. In addition, the effects of airflow speed and light conditions on the removal rates were also analyzed. The results demonstrated that applying electrical grounding to indoor plants significantly improved the particulate matter and airborne microorganisms removal rates. In the case of particulate matter removal, the grounded systems showed 75.7 ± 5.5% removal rate under air flow rate of 1.0m/s. Additionally, long-term experiments demonstrated that the grounded system maintained a stable particulate matter removal efficiency of over 60% for 35 days. Regarding airborne microorganisms removal, the grounded system achieved a removal efficiency of 63.3% ± 0.8% for airborne bacteria and 67.6% ± 1.6% for airborne fungi. This study confirmed that applying electrical grounding to indoor plants can significantly enhance their air purification performance. These results suggest that a simple grounding technique applied to potted plants can be an eco-friendly and effective solution for improving indoor air quality.