Abstract
In this work, copper (Cu) nanoparticles with observable surface plasmonic resonance (SPR) peaks were synthesized by an in-situ method. Chitosan host polymer was used as a reduction medium and a capping agent for the Cu nanoparticles. The surface morphology of the samples was investigated through the use of scanning electron micrograph (SEM) technique. Copper nanoparticles appeared as chains and white specks in the SEM images. The strong peaks due to the Cu element observed in the spectrum of energy dispersive analysis of X-rays. For the nanocomposite samples, obvious peaks due to the SPR phenomena were obtained in the Ultraviolet-visible (UV-vis) spectra. The effect of Cu nanoparticles on the host band gap was understood from absorption edges shifting of absorption edges to lower photon energy. The optical dielectric loss parameter obtained from the measurable quantities was used as an alternative method to study the band structure of the samples. Quantum mechanical models drawbacks, in the study of band gap, were explained based on the optical dielectric loss. A clear dispersion region was able to be observed in refractive indices spectra of the composite samples. A linear relationship with a regression value of 0.99 was achieved between the refractive index and volume fractions of CuI content. Cu nanoparticles with various sizes and homogenous dispersions were also determined from transmission electron microscope (TEM) images.
Highlights
A recent study revealed that nano-scale materials exhibit unique electronic and optical properties, which are unlike those in their bulk state [1]
The results shown in this paper reveals that a Cu nanoparticle significantly reduces the optical band gap of chitosan host polymer
Earlier studies have confirmed that the use of scanning electron micrograph (SEM) and energy dispersive analysis of X-rays (EDAX) techniques are sufficient to detect the formation of plasmonic metal nanoparticles in polymer composites [13,14,15,17,18]
Summary
A recent study revealed that nano-scale materials exhibit unique electronic and optical properties, which are unlike those in their bulk state [1]. Previous studies confirmed that the existences of lone pair electrons on chitosan functional groups are found to be responsible for complexation as well as reduction of silver ions to silver nanoparticles [14,15,16,17,18] Such problem can be overcome by the use of in-situ technique [19]. Earlier study revealed that hybrid (organic-inorganic) materials represents an intrinsic interdisciplinary field of research and development because it includes a variety of communities such as organometallics, colloids, soft matter, polymers, nanocomposites, biomaterials and biochemistry [20] This is related to the fact that organic-inorganic materials lie at the interface of the organic and inorganic areas. The effect of CuNPs on the optical properties of the chitosan host polymer was clarified
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
