Rational Design of High-Performance Bilayer Solar Evaporator by Using Waste Polyester-Derived Porous Carbon-Coated Wood

Wood-based bilayer solar evaporators,which possess cooperative advantages of natural wood and photothermal conversion coating including fast water transportation,low heat conduction,renewability,and high light absorbability,hold great promise for water purification.However,previous studies suffer from low evaporation rates and high cost of coatings,and lack a deep understanding how the porous structures of coating layer function.Herein,a novel bilayer solar evaporator is designed through facile surface coating of wood by low-cost porous carbon from controlled carbonization of polyester waste.The porous carbon bears rich oxygen-containing groups,well-controlled micro-/meso-/macropores,and high surface areas(1164 m^(2) g^(−1)).It is proved that porous carbon improves sunlight absorption and promotes the formation of numerous water clusters to reduce water evaporation enthalpy.Owing to these combined features,the bilayer solar evaporator exhibits high evaporation rate(2.38 kg m^(−2) h^(−1)),excellent longterm stability,and good salt resistance.More importantly,a large-scale solar desalination device for outdoor experiments is developed to produce freshwater from seawater.The daily freshwater production amount(3.65 kg m^(−2))per unit area meets the daily water consumption requirement of one adult.These findings will inspire new paradigms toward developing efficient solar steaming technologies for desalination to address global freshwater shortage.

Rapid chemical recycling of waste polyester plastics catalyzed by recyclable catalyst

Waste plastics are serious environmental threats due to their low degradability and low recycling rate.Rapid and efficient waste plastics recycling technologies are urgently demanded for a sustainable future.Herein,we report a rapid,closed-loop,and streamlined process to convert polyesters such as poly(ethylene terephthalate)(PET)back to its purified monomers.Using trifluoromethanesulfonic acid or metal triflates as the recyclable catalyst,polyesters such as PET can be completely depolymerized by simple carboxylic acids within 1 h.By coupling this acidolysis with a subsequent hydrogenolysis process,the consumed carboxylic acid was recovered and the closed-loop of PET depolymerization could be established.All catalysts and depolymerization agents are fully recycled while only PET and hydrogen are consumed.

Green synthesis of luminescent La-MOF nanoparticle from waste poly(ethylene terephthalate) for high-performance in Fe(Ⅲ) detection

Developing luminescent metal-organic frameworks(MOFs) capable of high-efficiency Fe^(3+)sensing has aroused great attraction in the fields of biology,chemistry,etc.However,previous solvothermal methods are limited by organic solvent usage,time consuming,high pressure,and high-energy consumption.Herein,we propose the waste-toMOF strategy towards the scale-up production of La-MOF nanoparticles through the ball milling of recycled poly(-ethylene terephthalate)(PET) bottles and La(NO_(3))_(3)·_(6)H_(2)O.PET goes on alkaline hydrolysis to form 1,4-benzenedicarboxylic acid sodium salt(Na_(2)BDC) and ethylene glycol by ball milling.Subsequently,BDC reacts with La^(3+)to form La-MOF.The as-prepared La-MOF crystal nanoparticles possess a rod-like morphology with the size of few hundred nanometers.Additionally,La-MOF nanoparticles display high selectivity and sensitivity for Fe^(3+)detection.The quenching constant and limit of detection are 5.29×10^(3)(mol·L^(-1))^(-1) and 0.147 μmol·L^(-1),respectively,thus surpassing many advanced Fe^(3+) sensors.According to the result of density functional theory,the high Fe^(3+) detection performance of La-MOF is related to the complexing of Fe^(3+)with La-MOF,which leads to the gradual dissociation of the coordination bond between terephthalic acid and La^(3+).It is anticipated that the mechanochemistry milling-based wasteto-MOF strategy provides a new platform for the massive production of functional MOFs in a green manner.

Application of microalgal-ZnO-NPs for reusing polyester/cotton blended fabric wastes after modification by cellulases enzymes

Polyester/cotton(PET/C)blended fabric wastes are produced daily in huge amounts,which constitutes an economic loss and an environmental threat if it is not reused appropriately.Modern textile waste recycling technologies put much effort into developing fabric materials with unique properties,such as bioactivity or new optical goods based on modern technologies,especially nano-biotechnology.In this study,zinc oxide nanoparticles(ZnO-NPs)were biosynthesized using the aqueous extract of Dunaliella sp.and immobilized on PET/C waste fabrics after enzymatically activated with cellulases.The produced Dunaliella-ZnO-NPs(10–20 nm with a spherical shape)were characterized by High-resolution transmission electron microscopy(HRTEM),Fourier-transform infrared spectroscopy(FTIR),X-Ray diffraction analysis(XRD),and Scanning electron microscopy-energy dispersive X-ray analyzer(SEM-EDAX),and some functional groups,such as CH,CO,NH,and CN(due to the presence of carboxyl,proteins and hydroxyl groups),were detected,revealing the biosynthesis of ZnO-NPs.The analysis showed that the resulting ZnO-NPS had potent antimicrobial effects,Ultraviolet(UV)protection capabilities,and no cytotoxic effects on the normal human fibroblast cell line(BJ1).On the other hand,enzymatic treatments of PET/C fabric waste with cellulases enhanced the immobilization of biosynthetic nanoparticles on their surface.Modified PET/C fabrics loaded with Dunaliella-ZnO-NPs showed antibacterial and UV protection capabilities making them an eco-friendly and cost-effective candidate for numerous applications.These applications can include the manufacture of active packaging devices,wastewater treatment units,and many other environmental applications.