Cellulose laminates represent a remarkable convergence of natural materials and modern engineering, offering a wide range of versatile applications in sustainable packaging, construction, and advanced materials. In this study, novel all-cellulose laminates are developed using an environmentally friendly approach, where freshly regenerated cellulose II films are stacked without the need for solvents (for impregnation and/or partial dissolution), chemical modifications, or resins. The structural and mechanical properties of these all-cellulose laminates were thoroughly investigated.
View Article and Find Full Text PDFThe first observation of cooling by anti-Stokes pumping in nanoparticle-doped silica fibers is reported. Four Yb-doped fibers fabricated using conventional modified chemical vapor deposition (MCVD) techniques were evaluated, namely, an aluminosilicate fiber and three fibers in which the Yb ions were encapsulated in CaF, SrF, or BaF nanoparticles. The nanoparticles, which oxidize during preform processing, provide a modified chemical environment for the Yb ions that is beneficial to cooling.
View Article and Find Full Text PDFWe report what we believe to be the first radiation-balanced fiber amplifier-a device that provides optical gain while experiencing no temperature rise. The gain medium is a silica fiber with a 21-μm-diameter core highly doped with Yb^{3+} (2.52 wt.
View Article and Find Full Text PDFLaser cooling in silica has recently been demonstrated, but there is still a lack of understanding on how fiber composition, core size, and contamination influence cooling performance. In this work, six Yb-doped silica fibers were studied to illuminate the influence of these parameters. The best fiber cooled by -70 with only 170 mW/m of absorbed pump power at 1040 nm, which corresponds to twice as much heat extracted per unit length compared to the first reported laser cooling in silica.
View Article and Find Full Text PDFFor the first time, to the best of our knowledge, laser cooling is reported in a silica optical fiber. The fiber has a 21-µm diameter core doped with 2.06 wt.
View Article and Find Full Text PDFNanomaterials (Basel)
August 2018
Transparent electrodes (TEs) made of metallic nanowires, such as Ag, Au, Cu, and Ni, are attracting increasing attention for several reasons: (1) they can act as a substitute for tin oxide-based TEs such as indium-tin oxide (ITO) and fluorine-doped tin oxide (FTO); (2) various methods exist for fabricating such TEs such as filtration, spraying, and Meyer bar coating; (3) greater compatibility with different substrates can be achieved due to the variety of fabrication methods; and (4) extra functions in addition to serving as electrodes, such as catalytic abilities, can be obtained due to the metals of which the TEs are composed. There are a large number of applications for TEs, ranging from electronics and sensors to biomedical devices. This short review is a summary of recent progress, mainly over the past five years, on silver nanowire-based TEs.
View Article and Find Full Text PDFDevelopment of cost-effective and environmentally friendly manufacturing methods will enable important advances for the production of large-scale flexible electronics. Laser processing has shown to be a promising candidate that offers a fast and non-destructive way to produce highly conductive patterns on flexible substrates such as plastics. However, an emerging option with a lower environmental impact is instead the use of cellulose-based flexible substrates, such as paper.
View Article and Find Full Text PDFMoS has been studied intensively during recent years as a semiconducting material in several fields, including optoelectronics, for applications such as solar cells and phototransistors. The photoresponse mechanisms of MoS have been discussed but are not fully understood, especially the phenomenon in which the photocurrent slowly increases. Here, we report on a study of the photoresponse flash-light-processed MoS films of different thicknesses and areas.
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