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Artificial photosynthesis has rapidly developed as an actual field of research, mimicking natural photosynthesis processes in plants or bacteria to produce energy or high-value chemicals. The nanocelluloses are a family of biorenewable materials that can be engineered into nanostructures with favorable properties to serve as a host matrix for encapsulation of photoreactive moieties or cells. In this review, the production of different nanocellulose structures such as films, hydrogels, membranes, and foams together with their specific properties to function as photosynthetic devices are described. In particular, the nanocellulose's water affinity, high surface area and porosity, mechanical stability in aqueous environment, and barrier properties can be tuned by appropriate processing. From a more fundamental viewpoint, the optical properties (transparency and haze) and interaction of light with nanofibrous structures can be further optimized to enhance light harvesting, e.g., by functionalization or appropriate surface texturing. After reviewing the basic principles of natural photosynthesis and photon interactions, it is described how they can be transferred into nanocellulose structures serving as a platform for immobilization of photoreactive moieties. Using photoreactive centers, the isolated reactive protein complexes can be applied in artificial bio-hybrid nanocellulose systems through self-assembly, or metal nanoparticles, metal-organic frameworks, and quantum dots can be integrated in nanocellulose composites. Alternatively, the immobilization of algae or cyanobacteria in nanopaper coatings or a porous nanocellulose matrix allows to design photosynthetic cell factories and advanced artificial leaves. The remaining challenges in upscaling and improving photosynthesis efficiency are finally addressed in order to establish a breakthrough in utilization of nanocellulose for artificial photosynthesis. [ABSTRACT FROM AUTHOR]

In this work, two types of pre-consumer textile waste, namely, viscose-rayon and nylon yarn, were utilized for nanocomposite filmmaking using the green solvent casting method. The nanocellulose was extracted from the viscose-rayon and incorporated as a filler in nylon films. The effects of nanocellulose on thermal, chemical, mechanical, structural, and barrier properties of films containing 0.1, 0.5, and 1 wt% nanocellulose were investigated in detail. The thermal study of films using differential scanning calorimetry (DSC) confirmed that adding nanocellulose into the nylon matrix does not act as a nucleating agent as nylon yarn waste already had ~5 wt% nucleating agents (thermogravimetric analysis, TGA). Rather, a decrease in the crystallinity of films was determined with the addition of nanocellulose. No significant changes in the mechanical properties were observed for nylon nanocomposite films. However, an increased hydrogen bonding was observed between the nanocellulose and nylon, along with the reorientation of hydrogen bonds (Fourier-transform infrared spectroscopy, FTIR). A dense cross-section and structured surface were observed in the scanning electronmicroscopic (SEM) images for nanocomposite films. The water vapor barrier of films increased as the concentration of nanocellulose increased in the nylon films and resulted in a 55% decrease in water vapor transmission rate (WVTR) compared to neat nylon film. [ABSTRACT FROM AUTHOR]