Surface modifications microemulsion studies

We have studied optical and photophysical properties of TiOj NPs, where the NPs are dispersed in the water core of a microemulsion. We have observed that the optical absorption of NP does not change in the microemulsion however, the emission quantum yield increases drastically. As an indirect band-gap semiconductor Ti02 NPs are nonemissive but due to the surface modification by surfactant molecules in the microemulsion the particles become emissive. 

In 2000, Pingbo et al. [59] synthesized nanocrystalline ZnS Mn using reaction via microemulsion method. They recorded PL spectra for different Mn concentrations and compared the luminescence with and without surface-modification. They also analized fluorescence lifetime for different emission wavelengths and reported that nanosecond decay is due to zinc vacancies and millisecond decay is attributed to Mn. They also studied the photo aging of their samples.The XPS measurements indicated the effect of surface-modification on the surface structure. 

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