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Abstract Incorporation of metallic nanoparticles (NPs) in polymer matrix has been used to enhance and control dissolution and release of drugs, for targeted drug delivery, as antimicrobial agents, localized heat sources, and for unique optoelectronic applications. Gold NPs in particular exhibit a plasmonic response that has been utilized for photothermal energy conversion. Because plasmonic nanoparticles typically exhibit a plasmon resonance frequency similar to the visible light spectrum, they present as good candidates for direct photothermal conversion with enhanced solar thermal efficiency in these wavelengths. In our work, we have incorporated ∼3-nm-diameter colloidal gold (Au c ) NPs into electrospun polyethylene glycol (PEG) fibers to utilize the nanoparticle plasmonic response for localized heating and melting of the polymer to release medical treatment. Au c and Au c in PEG (PEG+Au c ) both exhibited a minimum reflectivity at 522 nm or approximately green wavelengths of light under ultraviolet-visible (UV-Vis) spectroscopy. PEG+Au c ES fibers revealed a blue shift in minimum reflectivity at 504 nm. UV-Vis spectra were used to calculate the theoretical efficiency enhancement of PEG+Au c versus PEG alone, finding an approximate increase of 10 % under broad spectrum white light interrogation, and ∼14 % when illuminated with green light. Au c enhanced polymers were ES directly onto resistance temperature detectors and interrogated with green laser light so that temperature change could be recorded. Results showed a maximum increase of 8.9 °C. To further understand how gold nanomaterials effect the complex optical properties of our materials, spectroscopic ellipsometry was used. Using spectroscopic ellipsometry and modeling with CompleteEASE® software, the complex optical constants of our materials were determined. The complex optical constant n (index of refraction) provided us with optical density properties related to light wavelength divided by velocity, and k (extinction coefficient) was used to show the absorptive properties of the materials.
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Electrospun Cadmium Selenide Nanoparticles-Loaded Cellulose Acetate Fibers for Solar Thermal Application
Solar thermal techniques provide a promising method for the direct conversion of solar energy to thermal energy for applications, such as water desalination. To effectively realize the optimal potential of solar thermal conversion, it is desirable to construct an assembly with localized heating. Specifically, photoactive semiconducting nanoparticles, when utilized as independent light absorbers, have successfully demonstrated the ability to increase solar vapor efficiency. Additionally, bio-based fibers have shown low thermal conductive photocorrosion. In this work, cellulose acetate (CA) fibers were loaded with cadmium selenide (CdSe) nanoparticles to be employed for solar thermal conversion and then subsequently evaluated for both their resulting morphology and conversion potential and efficiency. Electrospinning was employed to fabricate the CdSe-loaded CA fibers by adjusting the CA/CdSe ratio for increased solar conversion efficiency. The microstructural and chemical composition of the CdSe-loaded CA fibers were characterized. Additionally, the optical sunlight absorption performance was evaluated, and it was demonstrated that the CdSe nanoparticles-loaded CA fibers have the potential to significantly improve solar energy absorption. The photothermal conversion under 1 sun (100 mW/cm2) demonstrated that the CdSe nanoparticles could increase the temperature up to 43 °C. The CdSe-loaded CA fibers were shown as a feasible and promising hybrid material for achieving efficient solar thermal conversion.
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- Award ID(s):
- 1944374
- PAR ID:
- 10230647
- Date Published:
- Journal Name:
- Nanomaterials
- Volume:
- 10
- Issue:
- 7
- ISSN:
- 2079-4991
- Page Range / eLocation ID:
- 1329
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/nano10071329
