A novel optical sensor for Pb2+ detection based on in-situ formation of Ruddlesden-Popper phase (C4H9NH3)2PbBr4 perovskite

• A novel type of sensor mechanism based on the in-situ formation of luminescent lead-based RP phase perovskite is proposed. • High selectivity of the sensor is achieved for water Pb 2+ detection. • The mechanism of the fluorescent sensor has been thoroughly discussed. On account of the concentration sensitive photoluminescence (PL) property of the lead-based Ruddlesden-Popper (RP) phase perovskite material, a novel sensing mechanism for highly selective Pb 2+ detection based on the in-situ formation of highly emissive luminescence structure matrix (C 4 H 9 NH 3 ) 2 PbBr 4 has been demonstrated. The sensor exhibits high sensitivity and selectivity for detecting Pb 2+ in complex metal cations mixture solution. This research reports a novel type of sensor mechanism based on the in-situ formation of luminescent lead-based RP phase perovskite. It paves the way for developing highly selective optical sensors for detecting heavy metal cations via their corresponding luminescence structure matrix.