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With the rapid development of the global economy, the increasingly serious problem of pollution of water resources. Accounted for a considerable proportion of the many water pollution, heavy metal pollution. Heavy metals is a dangerous pollutant, and long-term accumulation in vivo, resistant to degradation, toxicity generated serious harm to the ecological environment and human life and health. Traditional method for detection of heavy metal ions by atomic absorption spectrometry, atomic emission spectrometry, atomic fluorescence spectrometry and inductively coupled plasma - mass spectrometry, etc., these methods are complicated sample pretreatment operation time-consuming and expensive instruments, and other shortcomings, it is difficult to meet the site rapid detection requirements. In recent years, the study of chemical sensors has been widespread concern, as a new means of detection of heavy metal ions, with no pretreatment, low-cost, high sensitivity, good selectivity and advantages. Mesoporous molecular sieve as chemical sensors carrier has large specific surface area, pore regularly surface with a hydroxyl group, the synthesis process is simple, and the advantages of thermal stability. Luminescent molecules immobilized on mesoporous molecular sieves new photochemical sensor combines both advantages of luminescent molecules and mesoporous molecular sieves prepared to meet the needs of the actual detection of heavy metal ions. Luminescent molecules 4 - (2 - pyridylazo) resorcinol (PAR) immobilized after a bit of nitrogen - trimethoxysilyl propyl - nitrogen, nitrogen, nitrogen-bit - trimethyl ammonium chloride (TMAC ) functionalized mesoporous HMS prepared a new type of heavy metal ions detection role photochemical sensor HMS-TMAC-PAR. X-ray diffraction, Fourier transform infrared spectroscopy, thermal gravimetric analysis, elemental analysis, N2 physical adsorption and UV-visible diffuse reflectance spectroscopy to characterize this material, and colorimetric identification of the nature of the material, selectivity, sensitivity and repeat were studied. The results show that, in alkaline conditions, HMS-TMAC-PAR selective heavy metal ions, Fe3 Cd2 Ni2, Zn2 Pb2 Co2 Hg2 and Cu2 and other heavy metal ions to the mere mention the HMS-TMAC-PAR aqueous solution of the color from light yellow orange or light purple; under strong acidic conditions, HMS-TMAC-PAR for Cu2 have selective, only Cu2 aqueous HMS-TMAC-PAR changes color. At a pH = 12, HMS-TMAC-PAR water Cu2 has higher sensitivity, the detection limit of 0.81ppb, and can be reused after the EDTA treatment.
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