Enhanced photoluminescence of CdS quantum dots thin films on Cu and Ag nanoparticles

Fluorescent nanoparticles (NPs) exhibit unique optical properties which are utilized to prepare highly sensitive sensors. This paper illustrates the enhancement of luminescence emission of CdS quantum dots (QDs) from selfassembled metallic NPs of Cu and Ag. Metallic NPs, especially of Cu, Ag and Au exhibit unique and tunable plasmonic properties which are further manipulated by varying their size and shape. In the present study, plasmonic NPs were fabricated on glass substrate heated at 400 degrees C for the conversion of metallic layers into homogeneous NPs so as to create plasmonic response from these uniform NPs. The bimetallic layers of Ag and Cu NPs form a composite material having higher thermal conductivity, higher chemical stability and lower value of thermal expansion than monometallic layer of NPs. The photo-luminescence enhancement of CdS QDs thin films deposited on Cu and Ag NPs would find applications as light emitters and sensing devices. The attachment of CdS QDs on these bimetallic layers was confirmed by studying their optical properties. The morphology of the three prepared samples was analysed by scanning electron microscopy, which confirms the homogeneous deposition of spherical Cu and Ag NPs having size ranging from 20 to 55 nm (approximately). The above obtained outcomes illustrate the localized surface plasmon resonance characteristic of metal NPs which can be applied further for chemical and biological sensing

Automated summary

This study demonstrates the enhancement of luminescence emission of CdS quantum dots by self-assembled metallic NPs, highlighting the unique optical properties of metal NPs and their potential applications in sensors.