PEDOT:PSS/alginate conductive hydrogel as sustainable plant growth substrate

To mitigate global food shortages and address the environmental pollution and economic losses resulting from the high solubility and leaching of traditional fertilisers via farmland runoff, conductive hydrogels have emerged as a promising plant-growth substrate capable of delivering integrated electrical stimulation. In this work, we introduce a conductive hydrogel composed of PEDOT:PSS and sodium alginate (SA), which combines electrical conductivity with nutrient loading for controlled release. The resulting PEDOT:PSS/SA hydrogel demonstrates excellent conductivity and mechanical robustness, enabling low-voltage (0.5 V) electrical stimulation of plant growth while maintaining long-term stability of the hydrogel. In addition, the hydrogel supports controlled and sustained nitrate release, reducing nutrient loss by 17.3%. Under electrical stimulation, plants exhibit approximately 30% faster growth compared to those without stimulation. Overall, this conductive plant-growth substrate offers a sustainable approach for soilless cultivation systems aimed at enhancing crop yields.