A visible light excitable “on–off” and “green–red” fluorescent chemodosimeter for Ni2+/Pb2+

A pyrene derivative has been synthesized as a visible light excitable fluorescent chemodosimeter which exhibits “on–off” and “green–red” fluorescence behavior for Ni2+ and Pb2+ with different reaction speed, respectively, and its sensing ability toward metal cations and counter ions was investigated in detail. The high selectivity of the ‘in situ’ prepared Ni2+ and Pb2+ complexes toward EDA and the reaction speed difference provide two new effective methods for distinguishing between Ni2+ and Pb2+.