Sustainable Materials and Technologies最新文献

Phosphogypsum-based cementitious materials (PGCM) possess the potential to solidify corrosive ions in seawater and may serve as a viable alternative to Ordinary Portland Cement (OPC). However, despite this potential, limited research has explored the use of seawater as mixing water in PGCM, and the hydration mechanism underlying their interaction remains unclear. This study aimed to examine the impact of seawater on the macroscopic and microscopic characteristics of PGCM, as well as the underlying mechanisms and the evolution of PGCM properties in the presence of a synergistic effect between seawater and supplementary cementitious material, metakaolin (MK). The results demonstrate that using seawater as mixing water for PGCM mortars reduces workability. Conversely, sulphate ions in seawater shortened the induction period of PGCM, accelerated ettringite formation, shortened the setting time of PGCM, and enhanced the early strength of PGCM. However, the enhancement of the late strength of PGCM by seawater was limited. The synergistic effect of seawater and MK significantly increased the compressive strength of PGCM, with an enhancement of 45.31% and 20.48% at 28 and 90 days, respectively. This enhancement was linked to the hydration reaction of Na⁺ ions in seawater and MK, forming N-A-S-H gel network structure that influenced the microstructure of PGCM. Moreover, the incorporation of seawater and MK in PGCM offers both economic and environmental sustainability benefits.

The biosynthesis of zinc oxide nanoparticles (ZnONPs) offers great potential for plant disease management due to their potent antimicrobial properties and environmental safety. However, the precise mechanisms underlying their antifungal mode of action and role in suppressing mycotoxins remain unclear. This study aims to elucidate the mechanisms by which ZnONPs suppress the pathogenic fungus Fusarium graminearium, known to cause Fusarium head blight in wheat. Additionally, it investigates how ZnONPs mitigate the production of mycotoxins, which pose risks to humans and ruminants. The study demonstrates that ZnONPs, bioproduced by Pseudomonas poae (P. poae), inhibit not only fungal growth, colony formation, and spore germination, but also significantly reduce mycotoxin production of F. graminearium by inhibiting the synthesis of deoxynivalenol (DON), downregulating the FgTRI gene, and causing morphological alterations of the toxisomes. The results also highlight that ZnONPs exert significant effects on fungi through multiple mechanisms, including cell wall damage and the generation of reactive oxygen species (ROS). Moreover, ZnONPs effectively inhibit F. graminearium in wheat leaves and coleoptiles. Fluorescence microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and optical microscopy all show that ZnONPs stop F. graminearium from getting into wheat plants and colonising them. Overall, the findings of this study provide evidence that ZnONPs are highly effective in reducing F. graminearium colonization in wheat plants and effectively decreasing mycotoxin production through multiple pathways.

The feasibility of utilizing spent indium tin oxide (s-ITO) as an inert anode for the recovery of s-ITO targets through the electro-deoxidation was investigated, which concurrently achieved the avoidance of molten salt pollution caused by graphite anodes and maximized the utilization of resources by using the same material as the anode and cathode. Various techniques including anodic polarization and Tafel polarization were employed to evaluate the corrosion resistance and electrochemical stability of s-ITO. XRD and XPS are used to analyze the phase and valence state of the anodic materials and products, respectively. The practicability of replacing graphite anodes with s-ITO anodes was discussed in detail under identical electrolytic conditions. When using s-ITO as the anode, the carbon content and oxygen content in the electrolytic product are 31 ppm and 57 ppm, respectively, which are lower than those of graphite as the anode. Moreover, based on the results of above investigations, a cathode and anode collaborative electrolytic device was devised to maximize the utilization of resources and recovery of high-value products. The findings indicate that s-ITO has good corrosion resistance when used as an inert anode.

Copper, as a bulk metal, has been widely used around the world in the past decades. Historical consumption determines the supply of materials for recycling, as the scrap copper now available for recycling comes from previously manufactured products. The recycling of scrap copper has both resource and environmental properties, On the one hand, recycling scrap copper can make up for the shortage of primary copper supply, on the other hand, recycling scrap copper can reduce greenhouse gas and solid waste emissions, is one of the effective ways to achieve green and low-carbon manufacturing. However, the recycling of scrap copper is not only a technical problem, such as the increasingly complex raw material composition. As an important link in the global copper supply chain, it is also affected by trade and policy. In addition, new environmental problems may arise in the recycling process of scrap copper. The current distribution, supply, and demand of global scrap copper resources were introduced in this paper. The opportunities and challenges faced by the global scrap copper trade were analyzed. The resource attribute and potential environmental impact of scrap copper in the recycling process were expounded. The recovery process and technical route of typical scrap copper secondary resources were emphatically present. This review provides some reference for the sustainable recycling process of scrap copper.

Metal-organic frameworks (MOFs) are favored in the field of flame retardancy due to the catalytic effect of metal nodes on char layer formation and the synergistic flame-retardant effect of organic ligands containing elements such as nitrogen and phosphorus. However, the inherent microporosity of MOFs limits their adsorption efficiency for toxic smoke and flammable gases. In this work, an organic phosphorus-modified MOF with a distinctive nanostructure of hierarchically porous (P-Co-MOF/ZIF) was successfully synthesized. In brief, an amino-functionalized zeolitic imidazolate framework (NH₂-ZIF) was initially synthesized through a ligand substitution reaction with ZIF-67. Subsequently, organic phosphorus flame retardants were grafted on NH₂-ZIF, and the acidic substances generated during this process were used to synchronously half etch ZIF, resulting in a ZIF with a high specific surface area and unique nanostructure. Through this simple synthetic method, the catalytic ability of transition metals in ZIF is preserved, and organic phosphorus flame retardants are incorporated into ZIF, resulting in the synergistic flame-retardant effect of phosphorus and nitrogen. Additionally, its unique hierarchically porous nanostructure can effectively enhance the adsorption of volatile products during the combustion process, thereby offering outstanding flame retardancy and smoke suppression effects for epoxy resin (EP). The results indicate that adding 2 wt% P-Co-MOF/ZIF to EP can increase the limiting oxygen index value to 29.5%. Furthermore, the peak of heat release rate, total heat release, and total smoke production of the composite material can decrease by 43.3%, 37.9%, and 38.1%, respectively, compared to EP. Therefore, this work will provide new inspiration for designing functional nanostructures and synthesizing efficient flame retardants.

Modifying and controlling the viscoelasticity of asphalt is a major challenge for maintaining and managing paved roads and extending their life. To date, asphalt has been modified with petroleum-based synthetic polymers, mainly to improve its resistance to permanent deformation. While, we are developing an asphalt modifier, 2,3,4,6-O-tetrapalmitoylated-1,5-anhydro-d-glucitol (C16AG), which is obtained from starch and fatty acids as raw materials. Here, we performed various experiments to obtain insights into the mechanism of asphalt modification by C16AG. The results showed that the hardness of C16AG-modified asphalt showed a time dependence: it remained softer than the original unmodified asphalt for several hours after the addition of C16AG and then hardened depending on the amount of C16AG added. The time dependence of the hardness of the C16AG-modified asphalt is related to the modification mechanism and it is proposed to include the following processes: (1) C16AG mixes with the resin and asphaltene that usually cause the hardening of asphalt and (2) prevents the ordering of these components; (3) then spontaneous fiber network is formed slowly by C16AG.

Cellulose nanomaterials (CNs) are valuable, emerging green materials distinguished by their exceptional properties and a broad spectrum of potential applications in traditional and innovative fields. These nanomaterials exhibit high mechanical strength, a high aspect ratio, transparency, and a highly reactive chemical surface area. Additionally, they are biodegradable and produced from cellulose, an abundant and renewable resource. Such attributes position CNs as promising candidates in the rapidly growing sector of sustainable materials. However, like other nanomaterials in the developmental stage, the production, use, and end-of-life (EoL) management of these materials raise environmental, economic, and social concerns that need addressing. Emphasizing ecodesign and sustainable processes is crucial, particularly because the technologies for producing CNs are predominantly in the early to intermediate stages of technological maturity, as indicated by their low Technology Readiness Levels (TRL). Recognizing these challenges, this tutorial review aims to analyze the life cycle and environmental implications of CNs to enhance their ecodesign, an increasingly critical aspect of these emerging materials. To achieve this, a comprehensive review of peer-reviewed literature on the production processes and life cycle assessments (LCA) of CNs was conducted. This review systematically and thoroughly evaluates the environmental effects associated with various raw materials, processes, and applications from a life cycle perspective. By highlighting how methodological decisions can influence LCA outcomes, the review pinpoints critical impact areas and evaluates the environmental performance of CNs compared to alternative materials. Additionally, the review brings to light the main challenges, and identifies opportunities within LCA studies on CNs. A SWOT (strengths, weaknesses, opportunities, and threats) analysis was utilized to gather insights into the significance of integrating LCA in CN research for informed decision-making. This analysis has identified research opportunities, particularly in multi-product processes, multiple CN-based products, consequential modeling, and their end-of-life considerations. Future challenges include the need for primary company data, toxicity data for LCA, prospective LCA, and a multidisciplinary team with LCA expertise to address these issues. Drawing from the SWOT analysis, this review suggests a strategic framework to guide future LCA research on CNs, intending to improve their eco-friendly design and support the worldwide bioeconomy.

Developing advanced photocatalysts for antibiotics degradation is utmost importance in wastewater purification. Herein, we designed to a unique 1D/2D TiO₂/Bi₂O₂CO₃ (TBC) S-scheme heterojunction photocatalysts via a facile hydrothermal method, in which K₂Ti₈O₁₇-T nanowires are in situ transform into TiO₂ nanorod and then loaded on surface of Bi₂O₂CO₃ nanosheets. As-prepared TBC composites exhibited obviously enhanced photocatalytic removal activity for tetracycline (TC) degradation under visible-light irradiation, and the degradation efficiency achieved 86% after 60 min, which is significantly higher than pristine samples. This is because that the construction of 1D/2D heterojunction interface efficiently endowed the abundant surface oxygen vacancies and further boosted the separation and transfer of photoexcited carriers. Additionally, TBC composites maintained superior removal efficiency with continuous operation (600 min) in membrane reactor. The degradation pathway and toxicity estimation were also further investigated. In all, this work reported an integrated construction for 1D/2D S-scheme photocatalysts with efficient photocatalytic membrane removal for water purification.

Solar-driven interfacial evaporation coupled with hydroelectricity technology is regarded as a hopeful tactic to co-generate freshwater and electricity. However, constructing low-cost evaporators/generators remain a grand challenge. Herein, we report a salt-assisted carbonization method to convert waste polyethylene terephthalate to be hierarchically porous carbon nanosheet (HPCN) and build a flexible HPCN-based evaporator for freshwater and hydroelectricity co-generation. HPCN exhibits a wrinkled structure with the thickness of ca. 3.4 nm. The HPCN-based evaporator displays good hydrophilicity, high sunlight absorption (98%), high solar-to-thermal conversion, reduced water evaporation enthalpy, and low thermal conductivity. It exhibits high evaporation rate (2.65 kg m⁻² h⁻¹) and conversion efficiency (98.0%) through 1 kW m⁻² irradiation, exceeding many advanced solar evaporators. Importantly, the HPCN evaporator-based hydroelectricity generator realizes high voltage (255 mV) and current (310 nA) with good stability. The combination of large specific surface area with wealthy oxygen-containing groups of HPCN plays important roles in hydroelectricity generation. In outdoor experiment, the freshwater production amount from per meter square achieves 6.32 kg. This work provides a green approach to upcycle waste plastics to be functional carbon materials and offers a new platform to construct advanced evaporators for solar evaporation and hydroelectricity generation.

The conceptual design of yolk-shell structured Si/C composite materials is considered an effective approach to enhancing the structural stability of silicon-based anode materials over long cycles. Here, for the first time, zinc oxide is used as both the internal sacrificial layer and the external coating layer reactant, allowing it to be transformed into voids and the carbon layer precursor during subsequent operations. These internal voids can buffer the volume expansion of silicon, ensuring the electrode's integrity during cycling. The ZIF layer formed through in-situ solvothermal reactions can effectively reduce the occurrence of isolated ZIF in the solvent, resulting in better coating of the nano‑silicon particles. Compared to traditional processes for preparing yolk-shell structures, this gentle synthesis strategy avoids the use of HF, offering a new direction for large-scale production. This optimized yolk-shell Si/C-0.70 M electrode exhibits excellent rate performance (specific capacity of 988 mA h g⁻¹ at a high current density of 2 A g⁻¹) and long-term cycling stability (specific capacity of 722 mA h g⁻¹ after 300 cycles at a current density of 0.5 A g⁻¹; reversible specific capacity of 557 mA h g⁻¹ after 500 cycles). Therefore, this scalable study offers a new approach for safely producing yolk-shell anode materials with high cycle stability on a large scale.