Quaternary Phosphonium Salt-functionalized Graphene Filter for Effective Water Disinfection

To access safe water, a facile and low-cost quaternary phosphonium salt-functionalized graphene filter (PYQP-G filter) was developed via pi-pi stacking interaction between perylene and graphene surface. We first synthesized a new perylene derivative with two QPS groups at its amide sides denoted as PYQP. Next, shellac was used as a carbon source to coat the graphene material onto the surface of a porous SiO 2 substrate in a chemical vapor deposition (CVD) process. Thus, a graphene filter (G-filter) was obtained. Third, the PYQP was attached to the graphene surface through π-π stacking to generate the PYQP-G filter. Due to the high bacterial accumulation and killing ability of the assembled PYQP, the PYQP-G filter showed high efficiency in water disinfection. When the bacterial concentration is blown at 10 5 CFU/mL, one PYQP-G filter can purify up to 500 ml of water.