Biowaste-Derived Carbonized Bone for Solar Steam Generation and Seawater Desalination

AbstractInterfacial solar steam generation is an emerging strategy to improve the global freshwater supply. Herein, for the first time, a plausible alternative based on bone waste is presented for low‐cost solar steam generation and seawater desalination. This is accomplished via the exploration of the appropriate carbonization conditions for the successful bone transformation into a porous carbon‐based photothermal material. The carbonized bone (CB) not only is composed of inherent interlinked mesoporous microchannels for efficient water transportation but also displays broadband light absorption, photothermal conversion, and reduced vaporization enthalpy due to its special interactions with water. The as‐prepared CB shows an apparent evaporation rate of 1.82 kg m−2 h−1 under one‐sun illumination, attributed not only to its interaction with the sunlight but also to its performance in the dark field, and a solar‐to‐vapor conversion efficiency of 80%. Furthermore, CB desalinates water with an efficiency of 99.99%. Such performance combined with its wide availability, facile fabrication, and stability makes this biowaste‐based porous material a promising system for the production of freshwater. In this way, a valuable alternative for the valorization of bone‐based food‐waste is offered, paving the way to new routes for the management of such, continuously growing, food‐waste products

Cellulose Acetate and Cardanol Based Seed Coating for Intraspecific Weeding Coupled with Natural Herbicide Spraying

AbstractAgricultural pesticides can become persistent environmental pollutants and their use is destined to be reduced. Consequently, weed control is shifting to green products and strategies. A combined approach, made of pelargonic acid based herbicide spraying and interspecific competition (i.e. seeding of plants species competing for growth against weeds) could boost the weeding effect. In case of the contemporary seeding and spraying, needed to reduce costs, seed coating is necessary as barrier to herbicide toxic effects but, at the same time, the coating has to be endowed with the right features to allow germination. This work aims to verify the feasibility of using cellulose acetate/cardanol (CA/Card) as seed coating polymer–plasticizer blend and to identify possible relationship between material features and germination rate. For these purposes, untreated and pelargonic acid herbicide treated coated seeds coated through solvent evaporation methods (CA/Card ratios from 0/0 to 100/0) were subjected to germination test. Coatings were characterized through SEM, EDX, media uptake, DSC and mechanical analysis with and without conditioning in seeding conditions. Germination test showed that 70/30 seeds, treated and untreated with herbicide, presented the best germination rate. Germination assays showed that coating presence reduced and slowed (without stopping) seeds germination equally with and without herbicide treatment. Consequently, was possible to conclude that CA/Card coatings allowed germination and presented a barrier effect against herbicide. Thus coating resulted suitable for seed coating in herbicide spraying/interspecific combined applications. No strong correlations were found between material features and germination, but it is plausible to hypothesize that both water absorption and mechanical properties of the coating play an important role and have to be optimized to improve germination rate avoiding difficulty in sprouting. Finally, the study opened a new perspective in the use of cellulose acetate for seed coating from waste sources such as cigarette filters.Graphic Abstrac

Chirality at the Nanoparticle Surface: Functionalization and Applications

Chiral molecules, such as amino acids and carbohydrates, are the building blocks of nature. As a consequence, most natural supramolecular structures, such as enzymes and receptors, are able to distinguish among different orientations in space of functional groups, and enantiomers of chiral drugs usually have different pharmacokinetic properties and physiological effects. In this regard, the ability to recognize a single enantiomer from a racemic mixture is of paramount importance. Alternatively, the capacity to synthetize preferentially one enantiomer over another through a catalytic process can eliminate (or at least simplify) the subsequent isolation of only one enantiomer. The advent of nanotechnology has led to noteworthy improvements in many fields, from material science to nanomedicine. Similarly, nanoparticles functionalized with chiral molecules have been exploited in several fields. In this review, we report the recent advances of the use of chiral nanoparticles grouped in four major areas, i.e., enantioselective recognition, asymmetric catalysis, biosensing, and biomedicine

Biomass-based Porous Functional Materials for Photothermal Decontamination of Water

Water is extremely important for all living things. But global economic development, climate change, and population growth have put water resources under stress. Particularly, freshwater production is decreasing continuously. In the coming years, billions of people will be under water stress conditions. So, serious actions need to be taken. Interfacial solar steam generation is a promising and sustainable approach, which uses solar light as a renewable energy source with low environmental impact, to tackle freshwater scarcity. However, low solar absorbance and high heat losses cause poor solar-to-vapour conversion efficiency. In recent years, several photothermal materials have been developed to be used in solar evaporator devices, yet many problems need to be resolved. For instance, photothermal materials should be low-priced, eco-friendly, stable in harsh conditions, and easy to fabricate. Considering these factors, we have developed different sustainable photothermal functional materials using bone and vegetable waste, with highly porous structure, low weight, enhanced wettability, prolonged stability in water, high optical absorbance, low thermal conductivity necessary for that localization, and adequate solar-to-vapour conversion efficiency. The solar evaporation rate achieved is >1.1 kg m-2 h-1 with a solar-to-vapour conversion efficiency of >80% under 1 Sun irradiation. The prepared biomass-based materials can successfully desalinate artificial seawater, and decontaminate synthetic wastewater, (e.g. water containing dye molecules and hazard metal ions) with an efficiency of >98%. Most importantly the developed materials present salt anti-fouling ability and anti-bio-fouling properties. Thus, the multifunctional highly porous biocomposite photothermal materials prepared in this thesis are a cost-effective promising solution for prolonged wastewater decontamination processes. Last but not least, in this thesis, we also propose effective solutions to valorize food waste offering solutions to two major issues of modern society: water shortage and waste management