A Synthetic Hydrophyte for Sunlight-Driven Water Purification

The increased global use of pharmaceutical and personal care products (PPCPs) and their emissions into natural water bodies pose formidable challenges to ecosystem health. Because aquatic plants like hydrophyte natantia can effectively remove pollutants via photosynthesis-powered rhizoextraction and phytotransformation, they are widely applied in outdoor water purification; however, their performance in degrading recalcitrant PPCPs remains inefficient. Here, we develop a synthetic hydrophyte that mimics the main features of a natural hydrophyte: photosynthesis (leaves), pollutant degradation (stem), and pollutant extraction (root). CoOx/Mo:BiVO4/Pd artificial leaves photosynthesize hydrogen peroxide (H2O2), which is subsequently activated in the FeOCl artificial stem, generating powerful hydroxyl radicals (•OH) that rapidly degrade pollutants extracted by the poly(vinylidene fluoride) artificial root. The synthetic hydrophyte demonstrates remarkable degradation rates of 85.0-99.5% for multiple recalcitrant PPCP pollutants within 8 h, which are typically resistant to phytoremediation. In outdoor tests, the pollutant removal efficiency of the synthetic hydrophyte surpassed those of Hydrocotyle verticillata and Canna indica by 8.6-16.1-fold. Moreover, synthetic hydrophytes exhibit distinct advantages of high versatility under various pH, temperature, and water matrix conditions. The promising sunlight-driven water purification achieved by the synthetic hydrophyte sheds light on a new approach for achieving both efficient and sustainable removal of recalcitrant PPCPs that are increasingly detected in natural waters.