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1.
Adv Healthc Mater ; : e2401563, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39086039

RESUMEN

Bullous keratopathy, a condition severely impacting vision and potentially leading to corneal blindness, necessitates corneal transplantation. However, the shortage of donor corneas and complex surgical procedures drive the exploration of tissue-engineered corneal endothelial layers. This study develops a transparent, amphiphilic, and cell-free membrane for corneal endothelial replacement. The membrane, securely attached to the posterior surface of the cornea, is created by mixing hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethylacrylate (EGDMA) in a 10:1 ratio. A 50 µL volume is used to obtain a 60 µm hydrophobic membrane on both sides, with one side treated with a polyvinylpyrrolidone (PVP) solution. The resulting membrane is transparent, foldable, biocompatible, amphiphilic, and easily handled. When exposed to 20% sulfur hexafluoride (SF6), the hydrophilic side of the membrane adheres tightly to the corneal Descemet's membrane, preventing water absorption into the corneal stroma, and thus treating bullous keratopathy. Histological test confirms its effectiveness, showing normal corneal structure and low inflammation when implanted in rabbits for up to 100 d. This study showcases the potential of this membrane as a viable option for corneal endothelial replacement, offering a novel approach to address donor tissue scarcity in corneal transplantation.

2.
Front Genet ; 15: 1438276, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39092433

RESUMEN

Background: Low temperature pose significant challenges to peach cultivation, causing severe damage to peach buds and restricting production and distribution. Ethylene, an important phytohormone, plays a critical role in enhancing plant cold resistance. Structural genes and transcription factors involved in ethylene biosynthesis and signal transduction pathways are associated with cold resistance. However, no research has specifically addressed their roles in peach cold resistance. Methods: In this study, we aimed for cold-resistance gene discovery in cold-sensitive peach cultivar "21Shiji" (21SJ) and cold-resistance cultivar "Shijizhixing" (SJZX) using RNA-seq and gas chromatography. Results: The findings revealed that under cold stress conditions, ethylene biosynthesis in "SJZX" was significantly induced. Subsequently, a structural gene, PpACO1-1, involved in ethylene biosynthesis in peach buds was significantly upregulated and showed a higher correlation with ethylene release rate. To identify potential transcription factors associated with PpACO1-1 expression and ethylene signal transduction, weighted gene co-expression network analysis was conducted using RNA-seq data. Four transcription factors: PpERF2, PpNAC078, PpWRKY65 and PpbHLH112, were identified. Conclusion: These findings provide valuable theoretical insights for investigating the regulatory mechanisms of peach cold resistance and guiding breeding strategies.

3.
Food Chem ; 460(Pt 2): 140640, 2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39096801

RESUMEN

Melon fruit flavor is one of the most valuable traits for consumers. Aroma, formed by volatile organic compounds (VOCs), is a major component of flavor but has been neglected in breeding programs because of its complex regulation. Although the genetic regulation of VOCs biosynthesis is not fully understood, several advances have been recently achieved. VOCs originate from the degradation of fatty acids, aminoacids and terpenes, and the role of newly described enzymes, transcription factors and putative regulators is here discussed. Furthermore, ethylene plays a key role in fruit aroma production in melon, triggering the conversion of green-flavored aldehydes into fruity-flavored esters. A current challenge is to understand the ethylene-independent regulation of VOCs formation. Environmental conditions and human processing can also shape the melon volatile profile, and future research should focus on studying the effect of climate change in aroma formation.

4.
Small ; : e2405051, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39092657

RESUMEN

Metal-organic frameworks (MOFs)-related Cu materials are promising candidates for promoting electrochemical CO2 reduction to produce valuable chemical feedstocks. However, many MOF materials inevitable undergo reconstruction under reduction conditions; therefore, exploiting the restructuring of MOF materials is of importance for the rational design of high-performance catalyst targeting multi-carbon products (C2). Herein, a facile solvent process is choosed to fabricate HKUST-1 with an anionic framework (a-HKUST-1) and utilize it as a pre-catalyst for alkaline CO2RR. The a-HKUST-1 catalyst can be electrochemically reduced into Cu with significant structural reconstruction under operating reaction conditions. The anionic HKUST-1 derived Cu catalyst (aHD-Cu) delivers a FEC2H4 of 56% and FEC2 of ≈80% at -150 mA cm-2 in alkaline electrolyte. The resulting aHD-Cu catalyst has a high electrochemically active surface area and low coordinated sites. In situ Raman spectroscopy indicates that the aHD-Cu surface displays higher coverage of *CO intermediates, which favors the production of hydrocarbons.

5.
ACS Nano ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39109485

RESUMEN

The matching of poly(ethylene oxide) (PEO)-based electrolytes with ultrahigh-nickel cathode materials is crucial for designing new-generation high-energy-density solid-state lithium metal batteries (SLMBs), but it is limited by serious interfacial side reactions between PEO and ultrahigh-nickel materials. Here, a high-concentration electrolyte (HCE) interface with a customized Li+ solvation sheath is constructed between the cathode and the electrolyte. It induces the formation of an anion-regulated robust cathode/electrolyte interface (CEI), reduces the unstable free-state solvent, and finally achieves the compatibility of PEO-based electrolytes with ultrahigh-nickel cathode materials. Meanwhile, the corrosion of the Al current collector caused by lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) ions is prevented by lithium difluoro(oxalato)borate (LiDFOB) ions. The synergistic effect of the double lithium salt is achieved by a well-tailored ratio of TFSI- and DFOB- in the first solvation sheath of Li+. Compared with reported PEO-based SLMBs matched with ultrahigh-nickel (Ni ≥ 90%) cathodes, the SLMB in this work delivers a high discharge specific capacity of 216.4 mAh g-1 (0.1C) even at room temperature. This work points out a direction to optimize the cathode/electrolyte interface.

6.
Nano Lett ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39109989

RESUMEN

Organic solvent nanofiltration (OSN) membranes with high separation performance and excellent stability in aggressive organic solvents are urgently desired for chemical separation. Herein, we utilized a polyfunctional arylamine tetra-(4-aminophenyl) ethylene (TAPE) to prepare a highly cross-linked polyamide membrane with a low molecular weight cut-off (MWCO) of 312 Da. Owing to its propeller-like conformation, TAPE formed micropores within the polyamide membrane and provided fast solvent transport channels. Importantly, the rigid conjugated skeleton and high connectivity between micropores effectively prevented the expansion of the polyamide matrix in aggressive organic solvents. The membrane maintained high separation performance even immersed in N,N-dimethylformamide for 90 days. Based on the aggregation-induced emission (AIE) effect of TAPE, the formation of polyamide membrane can be visually monitored by fluorescence imaging technology, which achieved visual guidance for membrane fabrication. This work provides a vital foundation for utilizing polyfunctional monomers in the interfacial polymerization reaction to prepare high-performance OSN membranes.

7.
Sci Rep ; 14(1): 18142, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103411

RESUMEN

The impact of adding ethylene vinyl acetate copolymer (EVA 80) and 1 wt% TiO2 nanoparticles on the morphology and crystallization behavior of poly(lactic acid) blends was investigated using DSC, SEM, and POM. Thermal analysis revealed the enhancement of crystallinity of PLA in the presence of TiO2 and higher EVA 80 content in the blend. The PLA and EVA 80 components showed compatibility, as evidenced by the shift of the glass transition temperatures of the PLA phase in the blend to lower values compared to neat PLA. The lower temperature shift of the cold crystallization of the PLA and the formation of the small spherulites of the PLA in the blends indicated that the EVA 80 and TiO2 act as a nucleating agent for crystallization. The non-isothermal crystallization parameters of the composites were evaluated using Avrami's modified model, the MO approach, and Friedman's isoconversional method. The Avrami's modified rate constant (K) and the effective activation energy values significantly increased with the incorporation of EVA 80 and TiO2 nanoparticles. Furthermore, the thermogravimetric analysis (TGA) showed improved thermal stability of PLA by adding EVA 80 and TiO2.

8.
Angew Chem Int Ed Engl ; : e202411175, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39102295

RESUMEN

Purification of C2H4 from the ternary C2 hydrocarbon mixture in one step is of critical significance but still extremely challenging according to its intermediate physical properties between C2H6 and C2H2. Hydrogen-bonded organic frameworks (HOFs) stabilized by supramolecular interactions are emerging as a new kind of adsorbents that facilitate green separation. However, it remains a problem to efficiently realize the one-step C2H4 purification from C2H6/C2H4/C2H2 mixture because of the low C2H2/C2H4 selectivity. We herein report a robust microporous HOF (termed as HOF-TDCPB) with dense O atoms and aromatic rings distributed on the pore surface which provide C2H6 and C2H2 preferred environment simultaneously. Dynamic breakthrough experiments indicate that HOF-TDCPB can not only obtain high-purity C2H4 from binary C2 mixture, but also firstly realize one-step C2H4 purification from ternary C2H6/C2H4/C2H2 mixture, with the C2H4 productivity of 3.2 L/kg (>99.999%) for one breakthrough cycle. Furthermore, HOF-TDCPB displays outstanding stability in air, organic solvents and water, which endow it excellent cycle performance even under high-humidity conditions. Theoretical calculations indicate that multiple O sites on pore channels can create synergistic binding sites for C2H2, thus affording overall stronger multipoint interactions.

9.
Adv Mater ; : e2403728, 2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39097946

RESUMEN

Poly(ethylene terephthalate) (PET) is an important polymer with annual output second only to polyethylene. Due to its low biodegradability, a large amount of PET is recycled for sustainable development. However, current strategies for PET recycling are limited by low added value or small product scale. It is urgent to make a breakthrough on the principle of PET macromolecular reaction and efficiently prepare products with high added value and wide applications. Here, the catalyst- and solvent-free synthesis of biodegradable plastics are reported through novel carboxyl-ester transesterification between PET waste and bio-based hydrogenated dimer acid (HDA), which can directly substitute some terephthalic acid (TPA) units in PET chain by HDA unit. This macromolecular reaction can be facilely carried out on current equipment in the polyester industry without any additional catalyst and solvent, thus enabling low-cost and large-scale production. Furthermore, the product semi-bio-based copolyester shows excellent mechanical properties, regulable flexibility and good biodegradability, which is expected to substitute poly(butylene adipate-co-terephthalate) (PBAT) plastic as high value-added biodegradable materials. This work provides an environmental-friendly and economic strategy for the large-scale upcycling of PET waste.

10.
Artículo en Inglés | MEDLINE | ID: mdl-39102135

RESUMEN

In this study, the adsorption of a mixture of high-consumed drugs onto virgin and aged PET microplastics has been studied for the time ever. The target mixture comprised two anti-inflammatory drugs, diclofenac and ketoprofen, one anti-hypertensive, valsartan, and four common antibiotics, indomethacin, trimethoprim, isoniazid, and metronidazole. Two types of PET MPs (virgin and UV-aged) were used in the experimental procedure. Kinetic studies were conducted, and adsorption isotherms were obtained revealing the possible interactions that take place between adsorbents and adsorbates. Among the studied pharmaceuticals, diclofenac presents the highest uptake due to its hydrophobic nature, while aging appears to induce the adsorption of the drugs in MPs. Factors like pH or the environmental matrix were also evaluated. The results revealed that sorption is pH-dependent, while more complicated matrices like wastewater or seawater exhibit lower uptake than distilled water due to the natural organic matter present or the increased salinity, respectively. Finally, desorption studies were also conducted in three different aqueous solutions examining the pH effect. The desorption of the compounds was higher for diclofenac, followed by valsartan, and ketoprofen. The desorption percentages of antibiotics were quite low.

11.
EFSA J ; 22(8): e8914, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39099616

RESUMEN

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) assessed the safety of the recycling process Lietpak (EU register number RECYC327), which uses the EREMA MPR technology. The input material is hot caustic washed and dried poly(ethylene terephthalate) (PET) flakes originating from collected post-consumer PET containers, including no more than 5% PET from non-food consumer applications. The flakes are heated in a ■■■■■ reactor under vacuum. Having examined the challenge test provided, the Panel concluded that the ■■■■■ decontamination (step 2), for which a challenge test was provided, is critical in determining the decontamination efficiency of the process. The operating parameters to control the performance of this step are temperature, pressure and residence time. It was demonstrated that this recycling process is able to ensure a level of migration of potential unknown contaminants into food below the conservatively modelled migration of 0.1 µg/kg food, derived from the exposure scenario for infants, when such recycled PET is used at up to 100%. Therefore, the Panel concluded that the recycled PET obtained from this process is not of safety concern when used at up to 100% for the manufacture of materials and articles for contact with all types of foodstuffs, including drinking water, for long-term storage at room temperature or below, with or without hotfill. Articles made of this recycled PET are not intended to be used in microwave or conventional ovens and such uses are not covered by this evaluation.

12.
Artículo en Inglés | MEDLINE | ID: mdl-39107098

RESUMEN

The development of advanced liquid electrolytes for high-voltage/high-energy rechargeable Li metal batteries is an important strategy to attain an effective protective surface film on both the Li metal anode and the high-voltage composite cathode. Herein, we report a study of two CF3-substituted ethylene carbonates as components of the electrolyte solutions for Li metal|NCM811 cells. We evaluated trifluoromethyl ethylene carbonate (CF3-EC) and trans-ditrifluoromethylethylene carbonate Di-(CF3)-EC as cosolvents and additives to the electrolyte solutions. Using CF3-substituted ethylene carbonates as additives to a fluoroethylene carbonate (FEC)-based electrolyte solution enables improved capacity retention of high-power Li metal|NCM811 cells. The composition of the products from the transformations of CF3-EC and Di-(CF3)-EC in Li|NCM811 cells was studied by FTIR, XPS, and 19F NMR spectroscopy. We concluded that fluorinated Li alkyl carbonates are the main reaction products formed from these cyclic carbonates during the cycling of Li|NCM 811 cells, and fragmentation of the ring with the formation of CO2, CO, or olefins is not characteristic of CF3-substituted ethylene carbonates. The NCM 811 cathodes and Li metal anodes were characterized by X-ray diffraction, SEM, XPS, and FTIR spectroscopy. The role of CF3-substituted ethylene carbonate additives in stabilizing high energy density secondary batteries based on Li metal anodes was discussed. A bright horizon for developing sustainable rechargeable batteries with the highest possible energy density is demonstrated.

13.
ChemSusChem ; : e202401279, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107238

RESUMEN

Aromatic components of C8-C15 are playing indispensable roles in multi-functional properties of jet fuel. Here, we reported the controllable alkylation of benzene with mixed olefins of ethylene and propylene toward C8-C15 aromatic hydrocarbons for jet fuels over the bifunctional Ga/ZSM-5 catalyst. The resultant 2Ga/ZSM-5 exhibited a superior selectivity of 86.4% (yield of 55.5%) to C8-C15 range aromatics, at benzene conversion of 40.3%, ethylene and propylene conversion of 99.5% and 99.2%, respectively. The incorporation of Ga species could effectively weaken the strong acid sites of ZSM-5 and endow 2Ga/ZSM-5 catalyst with appropriate acidity, therefore facilitating the benzene alkylation process and suppressing the undesired hydrogen transfer or aromatization side reactions as well, thus improving the yield of desired C8-C15aromatics for jet fuels. This work provided insight into the development of promising bifunctional catalyst for the oriented transformation of biomass-derived chemicals to aviation fuels.

14.
FEMS Yeast Res ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39104224

RESUMEN

Plastics have become an indispensable material in many fields of human activities, with production increasing every year; however, most of the plastic waste is still incinerated or landfilled, and only 10% of the new plastic is recycled even once. Among all plastics, polyethylene terephthalate (PET) is the most produced polyester worldwide; ethylene glycol (EG) is one of the two monomers released by the biorecycling of PET. While most research focuses on bacterial EG metabolism, this work reports the ability of Saccharomyces cerevisiae and nine other common laboratory yeast species not only to consume EG, but also to produce glycolic acid (GA) as the main by-product. A two-step bioconversion of EG to GA by S. cerevisiae was optimized by a design of experiment approach, obtaining 4.51 ± 0.12 g L-1 of GA with a conversion of 94.25 ± 1.74% from 6.21 ± 0.04 g L-1 EG. To improve the titer, screening of yeast biodiversity identified Scheffersomyces stipitis as the best GA producer, obtaining 23.79 ± 1.19 g L-1 of GA (yield 76.68%) in bioreactor fermentation, with a single-step bioprocess. Our findings contribute in laying the ground for EG up-cycling strategies with yeasts.

15.
Chempluschem ; : e202400135, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963686

RESUMEN

The conversion of bioethanol to ethylene in gas phase and atmospheric pressure was investigated over γ-Al2O3 supported copper and nickel catalysts. These catalysts were prepared by co-precipitation and pre-treated with hydrogen at 450 °C. Six catalysts were studied at 450 °C under a nitrogen atmosphere. It was found that the monometallic Cu/γ-Al2O3 catalyst exhibited the highest ethylene concentration, with a selectivity of around 90%. The bioethanol conversion obtained was between 57%-86%. Another catalyst that exhibited high concentration values was the NiCu1:7 bimetallic catalyst. The catalysts were characterised using XRD, SEM, EDS, TEM, TGA, FTIR, Raman, and N2-physisoption techniques. Furthermore, the Cu/γ-Al2O3 catalyst was studied under different reduction temperatures and gas flow conditions. It was found that the catalysts reduced at 350 °C and 35 ml/min N2 flow presented ethylene concentrations between (0.18-0.21) g/L. Moreover, the catalyst deactivation was identified to be first order and the equation of the Cu/γ-Al2O3 catalyst deactivation model was determined. Carbonaceous deposits over the used sample were not detected by Raman and FTIR. It was determined that the Cu/γ-Al2O3 catalyst deactivation could be mainly attributed to the blocking of the catalytic sites by strongly adsorbed compounds and hydroxylation of the catalyst surface.

16.
Sci Rep ; 14(1): 15599, 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38971829

RESUMEN

Porous asphalt mixture is conventional hot mix asphalt (HMA) with substantially decreased fines, which produces an open-graded mixture that enables the water to flow through an interconnected void space. Porous asphalt is a permeable system that has a lot of benefits. However, because of its open structure, the durability of this mixture decreases, and both its stability and resilient modulus are much lower compared to the dense conventional asphalt mixtures. Also, the high void percentage may lead to an increase in the draindown proportion. Fibers (cellulose or mineral) and polymer-modified binders are recommended for porous asphalt mixtures, especially in hot and moderate climates. The objective of this study is to improve the porous asphalt mixture's performance by using ethylene-vinyl acetate (EVA) polymer-modified bitumen. Two types of fibers (cellulose fibers and glass wool fibers) were used, separately to determine the control mixture. Four different proportions of EVA polymer were added to the bitumen (1%, 2%, 3%, and 4%) and Scanning Electron Microscopy (SEM) was used for better investigating of the bitumen microstructure, then The Marshall mix design was used to determine the optimum EVA content (OEC) for the porous asphalt mixture. Several performance tests were conducted to investigate the characteristics of the porous asphalt mixture, such as the infiltration rate, binder draindown, the wheel track and the cantabro abrasion tests. The findings of the study conclude that the addition of EVA polymer to the porous asphalt mixtures enhances the performance as it increases stability by 20.8% and the infiltration rate by 20.6%. It decreases binder draindown proportion by 33.3%, cantabro abrasion loss by 25.1% and the rut depth at 5,000 cycles and 10,000 cycles by 29.8% and 19.7%, respectively.

17.
Physiol Mol Biol Plants ; 30(6): 985-1002, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38974358

RESUMEN

Present study would be significant in the sustenance of quality characters for postharvest storage of Capsicum fruit with CO2-sensitization in biocompatible manner. The present experiment describes effects of CO2 sensitization on delaying postharvest ripening through physiological attributes in Capsicum fruit. The experiment was conducted with acidified bicarbonate-derived CO2 exposure for 2 h on Capsicum fruit, kept under white light at 25 °C through 7 days postharvest storage. Initially, fruits responded well to CO2 as recorded sustenance of greenness and integrity of fruit coat resolved through scanning electron micrograph. Loss of water and accumulation of total soluble solids were marginally increased on CO2-sensitized fruit as compared to non-sensitized (control) fruit. The ethylene metabolism biosynthetic genes like CaACC synthase, CaACC oxidase were downregulated on CO2-sensitization. Accompanying ethylene metabolism cellular respiration was downregulated on CO2 induction as compared to control through 7 days of storage. Fruit coat photosynthesis decarboxylating reaction by NADP malic enzyme was upregulated to maintain the reduced carbon accumulation as recorded on 7 days of storage under the same condition. CO2-sensitization effectively reduced the lipid peroxides as oxidative stress products on ripening throughout the storage. Anti-oxidation reaction essentially downregulates the ROS-induced damages of biomolecules that otherwise are highly required for food preservation during postharvest storage. Thus, the major finding is that CO2-sensitization maintains a higher ratio of unsaturated to saturated fatty acids in fruit coat during storage. Tissue-specific downregulation of ROS also maintained the nuclear stability under CO2 exposure. These findings provide basic as well as applied insights for sustaining Capsicum fruit quality with CO2 exposure under postharvest storage. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-024-01471-4.

18.
Angew Chem Int Ed Engl ; : e202410646, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38972838

RESUMEN

Ethylene dimerization is an industrial process that is currently carried out using homogeneous catalysts. Here we present a highly active heterogeneous catalyst containing minute amounts of atomically dispersed Pd. It requires no co-catalyst(s) or activator(s) and significantly outperforms previously reported catalysts tested under similar reaction conditions. The selectivity to C4- and C6-hydrocarbons was about 80% and 10% at 42% ethylene conversion at 200°C using an industrially relevant feed containing 50 vol% ethylene, respectively. Our kinetic and catalyst characterization experiments complemented by density functional theory calculations provide molecular insights into the local environment of isolated Pd(II)Ox species and their role in achieving high activity in the target reaction. When the developed catalyst was rationally integrated with a Mo-containing olefin metathesis catalyst in the same reactor, the formed butenes reacted with ethylene to propylene with a selectivity of 98% at about 24% ethylene conversion.

19.
EFSA J ; 22(7): e8878, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38966136

RESUMEN

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) assessed the safety of the recycling process Fucine Film (EU register number RECYC322), which uses the Reifenhäuser technology. The input material consists of hot caustic washed and dried poly(ethylene terephthalate) (PET) flakes mainly originating from collected post-consumer PET containers, including no more than 5% PET from non-food consumer applications. The flakes are extruded under vacuum into sheets. The recycled sheets are intended to be used at up to 100% for the manufacture of materials and articles for contact with all types of foodstuffs, excluded drinking water and beverages, for long-term storage at room temperature, with or without hotfill. Based on the limited data available, the Panel concluded that the information submitted to EFSA was inadequate to demonstrate that the recycling process Fucine Film is able to reduce potential unknown contamination of the input PET flakes to a concentration that does not pose a risk to human health.

20.
Waste Manag ; 187: 275-284, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39083850

RESUMEN

The active silicon cell of a solar photovoltaic (PV) panel is covered by an ethylenevinylacetate (EVA) adhesive and a protective top glass layer. Separating this glass-EVA layer from the underlying silicon represents a bottleneck for recycling PV panels. Previous work has shown that the EVA-Si bond can be weakened by applying a continuous source of heat to melt the EVA. In this paper, a new method using nanosecond laser pulses is demonstrated to induce transient melting selectively at the EVA-Si interface. This impulsive heating method can cleanly separate the glass-EVA layer from the silicon in both model and commercial multicrystalline PV panels. The dependence of this debonding on parameters like laser pulse fluence (laser pulse energy per area), wavelength, applied pressure, and scan speed were characterized. For model PV panels, the single-pulse laser fluences required for spontaneous separation of the assembly under the force of gravity, were 0.23, 0.32 and 0.78 J/cm2 for 355 nm, 532 nm and 1064 nm, respectively. The use of shorter wavelengths reduces the laser fluence needed for debonding, while higher fluences can compensate for faster laser beam scanning rates. Optical and electron microscopy images of the Si surfaces before and after laser irradiation show that the textured antireflection layer is destroyed but the silver metal grid remains intact. Preliminary experiments using 532 nm pulses showed that the laser debonding method could remove the glass-EVA layer from sections of decommissioned commercial PV panels, even when the top glass layer was densely cracked.

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