Description of a new cellulosic natural fiber extracted from Helianthus tuberosus L. as a composite reinforcement material

Natural fiber-reinforced composites are generally known as eco-friendly, long-lasting, and recyclable materials. This study characterizes cellulosic&nbsp;Helianthus tuberosus L. fiber for polymer-based green composites for the first time.&nbsp;Helianthus tuberosus L. fiber has many advantages as a reinforcement material in polymer-based composites. For example, the high roughness of the fiber surface increases the locking into the composite body. One of the most critical advantages is its high thermal stability temperature of 247.3°C. Other advantages of the&nbsp;Helianthus tuberosus L. fiber are high cellulose content, high crystallinity, and high tensile strength. The hollow fiber structure allows its use in insulation materials. Finally, the high cellulose content of 62.65% supports its usage in various industries, including paper and paperboard manufacturing.</p

Enhancement of Optical and Photonic Properties of the Micro-sized ZnO Particles by Cerium Doping

Water shortage is one of the most urgent issues today, owing to rising population and environmental reasons. The most significant thing that humanity can do to solve this situation is to recycle waste or contaminated water. ZnO has been widely employed for photocatalytic applications due to its unique features. It was aimed to improve the photocatalytic properties of the micron-sized ZnO particles by doping with Cerium dopant, which is a rare earth element and used in many photocatalytic studies. Structural, morphological, optical, and photocatalytic properties were characterized to examine the effect of the Ce dopant ratio. The increased grain size demonstrated that Ce4+ was efficiently integrated into the ZnO lattice. Ce doping into the Wurtzite ZnO lattice improved both the emission and photocatalytic efficiency of the micro-sized ZnO particles. Additionally, it was revealed that the Ce doping procedure is more effective than grain size on the photocatalytic efficiency.</p

Opal and Inverse Opal Photonic Crystals

Photonic crystals are an emerging family of optical materials that control the behavior of photons in much the same way as crystalline semiconductors do it for electrons. Thus, they are considered to play a very important role in future’s photonic technology. Photonic crystals subject is one of today's popular study subject matters. These ordered structures ca be used in the applications of optical fiber, nanoscopic lasers, pigments, radio-frequency antennas, reflectors, light-emitting diodes, photonic integrated circuits, lasers, sensor, solar energy, photonic wave guides, optical insulators, optical imaging.Keywords: Inverse opal, photonic crystal, photonic band gap, laser, waveguide</p

Development of structural colored TiO2 thin films by varied etching solutions

Currently, one of the most important problems is water scarcity due to increasing population and environmental factors. Humankind can overcome this problem by recycling polluted water. The structural colors obtained from photonic crystal structures draw attention with fadeless bright color, combined with low toxicity and eco-friendliness. In this study, different etching/anodizing processes were applied to obtain Fabry-Perot and Photonic Crystal Ti-TiO2 structures. Structural colors owing to the morphology of the anatase phase on the surface of the samples etched with hydrochloric, sulfuric, and hydrofluoric acid-based solutions were obtained. The structural color of the formation on the titanium surfaces is related to the Fabry-Perot structures, while variations were correlated with Photonic Crystal surface morphologies. Because the high reflectance values contributed to the structural color formation, the photocatalytic efficiency of the samples etched with acid-based solutions was found to be lower than the samples etched with basic sodium and potassium hydroxide solutions. High-efficiency structural color reactors can be obtained by shifting the reflected wavelength range from the absorption wavelength range of the pollution material

Effect of anodizing time on the structural color and photocatalytic properties of the TiO2 films formed by electrochemical method

Environmentally friendly materials are gaining more and more importance day by day. Structural colored materials without chemical pigments have become popular in this respect. It was aimed to produce structurally colored, photocatalytic TiO2&nbsp;film coatings on the Titanium substrates using the anodizing method. Since the TiO2&nbsp;structure, which has photocatalytic properties, is not covered with any coating such as paint, the function of cleaning the environment with solar energy is preserved. The crystallite sizes of the anatase and rutile phases were found between 22.18 and 22.18&nbsp;nm. The highest photocatalytic efficiency was obtained at the sample anodized for 60&nbsp;s with 60% efficiency. The surface morphologies of the samples were transformed into a worm-like morphology after anodization for 600&nbsp;s. These regular indentations of the worm-like structure create extra coherent light scattering in the red region, similar to the photonic crystal surfaces. So, the main outcome is that the obtained colors can be controlled by Photonic Crystal morphologies. Also, extremely eco-friendly, multifunctional TiO2&nbsp;film coatings with both structural color and photocatalytic properties were obtained.</p

Extraction and Characterization of Natural Cellulosic Fiber from Taraxacum Sect. Ruderalia

The aim is to explore the utilization of cellulosic fibers extracted from the Taraxacum Sect. Ruderalia, which is also known as dandelion, introduces a potential reinforcement for the green composite industry. This research is focused on the analysis of chemical, physical, thermal, and morphological properties of the Taraxacum Sect. Ruderalia fibers. Its lightweight (1.397 g/cm(3)) with the presence of an acceptable cellulose ratio (52.7%) and high crystallinity (69.59%) provide comparable tensile strength (57.36 MPa) and Young's modulus (2.96 GPa) for Taraxacum Sect. Ruderalia fibers. The fibers are experimentally thermal resistant to 272 degrees C according to TGA that may be profitable in extrusion processes in polymeric composite manufacturing. The average fiber diameter and wall thickness were optically 233 mu m and 1.5 mu m, respectively. Taraxacum Sect. Ruderalia fibers have a rough surface character with some irregularities such as porosities, particles, indentations, protrusions, and also the microfibrillar structure which can support mechanical interlocking with polymer in a composite system. With all these encouraging properties, Taraxacum Sect. Ruderalia fibers can be good alternative reinforcement for common cellulosic bast fibers in the development of ecologically friendly and sustainable polymeric-based materials