Search Results (286)

The construction sector plays a significant role in global energy consumption and carbon emissions; improving the energy efficiency of existing buildings a fundamental requirement for sustainable development. Retrofitting the internal walls of buildings requires insulating materials that not only provide effective thermal performance but are also environmentally friendly, low-carbon, and compatible with circular-economy principles. In this context, recycled textile materials, especially cotton and polyester, are gaining increasing attention as sustainable insulation systems. This review article aims to critically evaluate the thermal insulation, environmental performance, and potential use of woven textile insulation structures based on recycled cotton, recycled polyester, and an equal combination of both in internal wall retrofitting. This article systematically reviews the available scientific literature and presents a conceptual framework based on multilayer woven structures. This review highlights that increasing the number of layers can play a significant role in improving thermal resistance, reducing heat transfer, and limiting internal energy loss by increasing the static air spaces between the fibers. Furthermore, the use of recycled textiles can also achieve environmental benefits such as reducing textile waste, conserving natural resources, and reducing overall carbon emissions. The research also offers a useful guiding framework for the development of sustainable building technologies based on low-carbon construction, efficient use of resources, and a circular economy. Full article

The valorization of agricultural waste into high-value carbon nanomaterials offers dual benefits: it reduces pollution and provides low-cost materials for sustainable technologies. This work synthesizes graphene-like carbon from Ghars date waste via mild KOH-assisted pyrolysis at 1000 °C. The material (G-GhW1000) exhibits a sharp (002) XRD peak at 26.16° (d-spacing = 3.40 Å), a characteristic π → π* transition at 253 nm, and a high C/O ratio of 27.37. Dispersed in tap water (0.5 g/L) by simple hand shaking (without ultrasonication), it serves as a photothermal nanofluid in a modified single-slope solar still (MSS). Under outdoor conditions, the MSS produces 4.69 L·m⁻²·day⁻¹, which is 18.7% higher than a conventional still, with thermal efficiency rising from 27.2% to 30.8% (with a reproducible 19.0% enhancement in summer). Samples prepared at 800 °C and 900 °C give 4.0% and 6.4% lower yields, while the 1100 °C sample gives only 6.0% improvement, confirming 1000 °C as the optimal temperature. The superior performance at 1000 °C is attributed to the optimal balance between graphitization, deoxygenation, and structural integrity, as evidenced by XRD, FTIR, EDX and UV-Vis analyses. The enhanced performance is linked to higher water temperature (68 °C) and larger ΔT. The distilled water meets WHO standards (TDS 9.35 mg/L, >99.4% reduction) with no detectable graphene-like carbon carryover. This work demonstrates the potential of waste-derived graphene-like carbon as a low-cost additive for solar desalination, addressing water scarcity and waste management within a circular economy framework. To our knowledge, this is the first study to use Ghars date waste-derived graphene-like carbon in a solar still. Full article

The prevention of coal mine fires and the sequestration of CO₂ represent two grand challenges that have traditionally been addressed separately. Here we report a CO₂-modified bentonite-based sealing material that concurrently achieves fire resistance, gas sealing and mineral-carbonation CO₂ uptake through rational materials engineering. In this work, “carbon-negative” is used as a comparative property: the material’s cradle-to-gate embodied emissions combined with its measured 28-day mineral uptake are lower than the cradle-to-gate footprint of a conventional cement-based benchmark under the stated system boundary. High-pressure CO₂ intercalation expanded the montmorillonite d-spacing from 12.48 to 14.79 Å and introduced carbonate functional groups (1435 cm⁻¹), as confirmed by FTIR and XRD. Systematic optimization of a bicomponent formulation incorporating municipal solid waste incineration slag and CO₂-saturated zeolite yielded a material with 28-day compressive strength of 37.9 MPa, a fire resistance limit of 186 s and O₂ reduction from 13.7% to 4.9%. Notably, carbon sequestration reached 24–40 kg CO₂ per ton through mineral carbonation, validated by carbonate peaks in FTIR and calcite detection in XRD. Carbon accounting based on a cradle-to-gate inventory (342–408 kg CO₂-eq/t) combined with the measured 28-day mineral uptake (24–40 kg CO₂/t) yields a comparative net balance of −46 to −188 kg CO₂-eq/t relative to a conventional cement-based benchmark under the stated system boundary. The synergistic mechanism involves CO₂-modified bentonite-regulating layer spacing, alkali-activated slag releasing Ca²⁺/Mg²⁺ for carbonate precipitation, and zeolite providing endogenous carbon slow-release. This work establishes a materials-chemistry paradigm for transforming industrial waste streams into functional carbon sinks while addressing critical mining safety needs. Full article

Secondary raw materials (SRM) such as phosphogypsum, pyritic mining wastes, and metallurgical slags constitute increasingly important alternative sources of critical raw materials within circular economy strategies. However, these materials commonly exhibit strong compositional heterogeneity at micro- to millimeter scales, making their characterization challenging using conventional bulk analytical approaches. This study presents a multivariate n-dimensional synthetic µ-XRF fluorescence mapping workflow for the automated characterization and classification of heterogeneous secondary resources. High-resolution µ-EDXRF elemental maps were integrated into multidimensional feature spaces combining elemental intensities, spatial relationships, and statistical descriptors. Unsupervised machine learning approaches, including hierarchical clustering, K-means and Gaussian mixture models (GMM), were applied to identify compositional domains and reconstruct synthetic fluorescence maps representing statistically coherent elemental associations. Case studies involving phosphogypsum and slag resulting from pyrite roasting demonstrate the capability of the proposed workflow to distinguish complex mineralogical textures, identify elemental associations related to critical raw materials, and detect environmentally relevant compositional domains. The developed methodology provides a non-destructive and transferable computational framework for advanced secondary resource characterization and process-oriented evaluation of complex waste-derived materials. Full article

The accumulation and persistence of plastic waste have made microbial plastic biodegradation an important topic in pollution control, environmental remediation, and sustainable materials management. This study combines a mini-review with bibliometric analysis to link mechanistic understanding with global research trends in microbial plastic biodegradation from 2000 to 2025. The mini-review summarizes polymer weathering and fragmentation, microbial colonization and biofilm formation, extracellular depolymerization or oxidative chain cleavage, uptake and intracellular catabolism of plastic-derived intermediates, physiological regulation, ecological interactions, and potential applications in bioremediation and upcycling. Bibliographic records were retrieved from the Web of Science Core Collection and analyzed using bibliometrix, VOSviewer, CiteSpace, and SCImago Graphica. A total of 2959 publications were identified. Publication output increased markedly, especially after 2018, reaching 617 publications in 2025; cumulative citations reached 31,373. China, India, and the United States were the leading contributors. Journal and keyword analyses showed strong links among environmental science, polymer science, microbiology, biotechnology, and engineering. Highly cited publications mainly focused on plastic biodegradability, biodegradable polymers, engineered PET depolymerization, polyethylene degradation, and microbial or enzymatic degradation mechanisms. Keyword evolution revealed a shift from material-oriented topics, including polymer blends, poly(vinyl alcohol), polyesters, morphology, mechanical properties, composites, and polyhydroxyalkanoates, toward degrading enzymes, cutinase-like enzymes, plastic-degrading strains, microbial colonization, fungi, and marine environmental degradation. Overall, microbial plastic biodegradation has evolved from material-centered biodegradability evaluation toward a mechanism-oriented and environment-oriented interdisciplinary field. Full article

Growing urbanization, housing affordability pressures, and increasing sustainability demands have positioned modular and flexible design strategies as central approaches in contemporary residential architecture. Modularity enhances construction efficiency, reduces material waste, and accelerates delivery through the use of prefabricated, standardized components. Flexibility, in turn, enables spaces to adapt in configuration and function over time, responding to the evolving needs of occupants and communities. Following PRISMA 2020 guidance, a systematic search was conducted across Web of Science, Scopus, and ScienceDirect academic databases resulting in 2140 records. After duplicate removal and sequential screening, 98 studies were included in the final review. The selected literature spans peer-reviewed journal articles and documented case studies, with emphasis on publications from 2015 onwards. The review identifies key advantages of modular and flexible residential systems, including cost-effectiveness, reduced environmental impact, and improved user satisfaction, while also highlighting persistent challenges such as regulatory barriers, standardization constraints, and limited interdisciplinary integration. The review contributes three synthesis outputs: a typology of modular residential systems, a critical comparison of modular–flexible strategies, and a cross-scale conceptual framework linking production logic, occupant adaptation, and sustainability outcomes. The findings underscore the potential of hybrid strategies that combine modular construction with flexible design principles to produce residential environments that are resilient, adaptable, and sustainable. The review provides structured insights and evidence-based recommendations for architects, planners, and policymakers involved in the development of future housing systems. Full article

Ceramic production generates large quantities of fired waste that is durable, non-biodegradable, and increasingly difficult to manage through conventional waste disposal practices. This study analyzes how ceramic waste is transformed into sustainable value in Jingdezhen, China, a city where ceramic production and cultural heritage have developed over more than a millennium. Using a qualitative multiple-case design, this study examines representative cases from three ceramic waste reutilization pathways: industrial reuse, environment-oriented reuse, and craft-based artistic reuse. The analysis shows that ceramic waste creates sustainable value through three interconnected processes: material transformation, economic activation, and cultural re-signification. Industrial cases primarily promote resource recovery and product innovation; public and environmental projects improve environmental awareness by integrating ceramic waste into urban spaces; and artistic practices reinterpret discarded ceramics as a medium for historical reflection, cultural expression, and public engagement. Based on these findings, the study proposes a material economic cultural analytical framework that explains how these value dimensions interact to transform ceramic waste from an environmental burden into a strategic resource. This study goes beyond documenting feasible ceramic waste recycling models by demonstrating that effective circular resource management in heritage-based industrial regions depends not only on technical recycling practices but also on cultural connotations and public recognition, which, together, generate value across environmental, economic, and cultural significance. These findings extend the scope of circular economy research by demonstrating a viable pathway for heritage-based industrial regions to leverage their own cultural heritage in transforming ceramic waste into environmental, economic, and cultural value. They also provide a practical model for other heritage-based regions seeking to align waste management with sustainable development. Full article

The nesting and cutting of thin materials are critical processes in industrial manufacturing, often involving multi-layer stacking to optimize production efficiency. However, material defects complicate the process, requiring optimization of both layout and defect avoidance under multi-layer heterogeneous constraints. Moreover, existing methods struggle with large search spaces and high computational complexity, limiting their industrial applicability and affecting material utilization and machining accuracy. To address these challenges, we propose HGATrans-MNCD, an intelligent nesting optimization algorithm that integrates defect avoidance and material waste reduction. Initially, areas with high defect overlap are prioritized using an enhanced No-Fit-Polygons strategy to ensure global defect avoidance. A heuristic approach is then employed to optimize the initial nesting sequence. Subsequently, a Transformer-based module leverages prior knowledge to efficiently perturb and refine the sequence, facilitating global optimization. Experiments on a benchmark dataset of multi-layer defect scenarios demonstrate that HGATrans-MNCD effectively addresses irregular defect patterns, enhancing material utilization by 2–8%. Our algorithm performs especially well in scenarios involving spatially coupled defects, offering a novel solution to complex multi-constraint optimization problems. Full article

Recirculating organic byproducts like food waste, wastewater and manure efficiently and at scale in a circular bioeconomy will be critical to ensuring future food security, energy security, climate resilience, water security and environmental health. Ultimately, we will not be able to live within the safe operating space of our planetary boundaries if we do not stop our wasteful and inefficient habits. Our food, waste, energy and water sectors are starting to transform towards circularity, driven by a diverse range of drivers, from net zero emissions targets, to food waste policies, and to rising fertiliser prices and geopolitical risks. However, these sectors are often not transforming in a coordinated manner, risking unintended consequences like competition between end-uses, technology lock-in, the prevention of scalability, or failure to achieve key sustainability targets, causing rebound effects. For example, society’s organic waste is being earmarked for the production of bioenergy, sustainable aviation fuels, biomaterials, and biofertilisers; however, it is not clear if there will be a sufficient supply of organic waste to meet these diverse demands. Phosphorus flow analyses indicate that we will need to secure almost all of the nutrients in organic waste as fertiliser raw material to produce food. There are some existing pockets of innovation within sectors related to food waste, water and wastewater, fertilisers and agriculture, and bioenergy. However, many initiatives are being driven by short-term challenges, are not operating at scale, or are not sufficiently integrated across sectors. In this paper, we provide examples of innovations and challenges from around the world, including Italy, Australia, Sri Lanka, the UK, Japan, and Malawi. This paper identifies a pathway to navigate tensions to achieve co-existing sustainability goals, including key enablers and barriers, ranging from overcoming regulatory fragmentation to a lack of capital investments. Creating a truly viable circular economy for organic byproducts requires the integration of policies, markets, technologies and people. This means engaging diverse stakeholders, from local councils and private waste contractors, farmers, and fertiliser companies to energy retailers and wastewater utilities, NGOs, informal collectors, and environmental regulators and policy-makers. Full article

Upcycling biomass waste into value-added battery materials is crucial for sustainable energy storage. Here, we transform coffee grounds into high-performance hard carbon (HC) anodes for sodium-ion batteries (SIBs) via a synergistic pre-oxidation and acetylene chemical vapor deposition (CVD) strategy, which effectively reduces open pores and promotes structural stabilization. The resulting material exhibits features consistent with a closed-pore architecture. Pre-oxidation incorporates oxygen-containing functional groups that template accessible pores and expand the interlayer spacing during carbonization. Subsequent CVD covers surface pores and contributes to the stabilization of the pore structure. The optimized HC (COF300&1300@C) exhibits a balanced set of structural features, including a low specific surface area (2.1 m² g⁻¹), expanded interlayer distance (0.391 nm), and a well-regulated pore system with reduced surface area and controlled pore size. As a result, it delivers a reversible capacity of 298 mAh g⁻¹ with an ICE of 70%, and remarkable cycling stability (97% capacity retention after 500 cycles at 1C). This study elucidates the synergistic mechanism of pre-oxidation and CVD in reducing open pores and stabilizing the pore architecture, thereby yielding characteristics indicative of closed-pore behavior, and providing a novel and efficient approach for designing high-performance biomass-derived hard carbons for energy storage. Full article

The development of sustainable, high-performance construction materials is essential for enhancing the resilience and economic efficiency of infrastructure in seismically active regions. Although nanomaterials can improve concrete performance, the combined influence of hybrid nanomaterial systems—particularly those sourced from agricultural and industrial waste streams—on early-age behavior, building-scale seismic response, and cost efficiency remains insufficiently quantified. This study presents an integrated experimental and numerical assessment of high early-strength concrete (HESC) incorporating nano-silica (NS), nano-clay (NCl), and cellulose nanofibers (NCels). Experimental results indicate that the optimized mixture (HESC-O) achieved a 3.15-fold increase in 28-day compressive strength, a 93.3% reduction in water penetration depth, and an 88.7% decrease in corrosion rate compared with conventional concrete. Finite element analyses of low-, mid-, and high-rise building models showed that HESC-O increased lateral stiffness and reduced story drift by up to 30% compared to normal concrete (NC); improvements over reference HESC (HESC-R) were of 5–10% and lateral displacement differed by 25–40%, with the most pronounced improvements observed in taller structures. Despite a higher unit material cost, the cost–benefit analysis demonstrated substantial net savings, particularly for high-rise buildings, primarily due to a 52% reduction in column cross-sectional areas and the associated increase in usable floor space. The findings support the performance-based selection of nano-engineered concrete that balances structural performance, economic value, and sustainability. Full article

Magnesium hydroxide is attracting growing interest as a versatile, halogen-free flame retardant, and this review surveys its production routes, structure–property relationships and use in polymer systems from commodity polyolefins to advanced bio-based materials. Industrial Mg(OH)₂ is still predominantly obtained from mining or hydration of MgO, but increasing attention is being devoted to recovery from seawater and saltwork brines, where precipitation from Mg²⁺-rich streams followed by controlled rehydration or direct precipitation yields fine, high-purity powders suitable for flame retardant use and simultaneously valorizes saline wastes. In parallel, hydrothermal synthesis has been extensively explored to tailor particle size and morphology by adjusting the precursor, solvent, temperature and time, enabling high-surface-area Mg(OH)₂ or MgO with narrow size distributions that are attractive for high-performance composites also evaluated via ball milling, crushing and refining. More recently, process intensification strategies such as microwaves and ultrasounds have been proposed to shorten reaction times, lower temperatures and better control nucleation and growth, opening paths toward energy efficient production of structured Mg(OH)₂ from both conventional and brine-derived precursors. The second part of the review analyzes how the intrinsic endothermic decomposition and basic character of Mg(OH)₂ can be utilized across a broad range of polymer matrices and how surface functionalization strategies extend its applicability. In addition to “as received” powders, stearic acid and other fatty acids, metal soaps and various organic coupling agents are widely used to render the surface more hydrophobic, enhance dispersion and interfacial adhesion, and in some cases introduce additional char-forming or barrier functionality. In terms of the application, the review methodically synthesizes and contrasts fire and mechanical data for Mg(OH)₂-containing polyolefins (HDPE, LLDPE, PP and EVA) utilized in cables and building products, expandable polymers and foams, biopolymers (PLA and PBS), and elastomers. The review places particular emphasis on the balance between loading level, processability, flame performance and mechanical integrity. This review aims to provide a comprehensive framework for designing next-generation Mg(OH)₂-based flame-retardant systems for both conventional and emerging polymer technologies. To this end, it integrates advances in sustainable feedstocks, controlled synthesis and surface engineering with the rapidly expanding application space. Full article

Currently, construction uses a vast array of materials that, while serving the same purpose, differ only slightly in their properties. This complicates the substitution of one material for another, significantly expanding the product range when considering operating conditions, necessitating expanded warehouse space. Therefore, preference should be given to universal materials that, while maintaining the same chemical composition, can change their properties by altering the ratio of their components. This study addresses this issue by evaluating the potential of glass composites containing powdered waste glass as alternatives to selected conventional construction materials. The results demonstrated that the rheological properties of the composites can be effectively controlled by adjusting the ratio of water glass to waste glass powder, enabling the achievement of viscosity values suitable for both plastering and installation mortars. In addition, the composites exhibited markedly higher adhesion strength than conventional gypsum mortars under high-humidity conditions, confirming their applicability as adaptable, substrate-specific materials with geopolymer-like characteristics. Full article

A series of Mg-Al LDH-based photocatalysts were synthesized via a one-pot steam-assisted method, including pure Mg-Al LDH (MA), Zn-In ion-exchange-modified Mg-Al LDH (MAZ), BiOCl-loaded pristine Mg-Al LDH (MAB), and Zn-In-modified Mg-Al LDH co-loaded with TiO₂ and BiOCl (MA/Zn-In/TiO₂/BiOCl, MAZB). The one-pot synthesis facilitated the in situ intercalation and uniform loading of BiOCl/TiO₂/Zn-In, while Zn²⁺/In³⁺ modified the MA layers via ion exchange, leading to an expansion of the interlayer spacing. The innovation of this work is reflected in two aspects: first, all raw materials are added via a one-pot strategy to achieve in situ preparation of modified hydrotalcite; second, this synthetic route features simple post-treatment without complicated washing, pressure filtration, and other tedious operations. The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and N₂ adsorption–desorption isotherms. The bismuth chloride oxide/TiO₂/LDHs exhibited a layered structure, with the active components uniformly distributed between the layers and on the MA surface. Under simulated sunlight irradiation, MAZB achieved 97.5% degradation of 20 mg/L MB within 120 min, with an apparent rate constant of 0.0297 min⁻¹, which is 7.2 times, 2.4 times, and 2.9 times that of MA, MAZ, and MAB, respectively. The degradation rate of MAZB still remained at 89.5% after five cycles, demonstrating excellent stability and reusability. Compared with traditional hydrothermal methods, this steam-assisted system features mild reaction conditions (180 °C, atmospheric pressure), sodium-free raw materials, no washing requirement, and zero waste discharge, showing prominent green advantages. Full article

3D concrete printing (3DP) enables automated construction with reduced material waste and enhanced geometric flexibility. However, its structural performance remains sensitive to anisotropy, mix design, and printing parameters, thereby complicating quality control. Self-sensing cementitious materials provide a promising approach by enabling intrinsic strain monitoring during fabrication and service. In this study, a hybrid multi-material printing strategy was developed using a conductive cement-based mix incorporating graphite (G), milled carbon microfibers (MCMF), and chopped carbon microfibers (CCMF), alongside a plain cement-based matrix. Based on percolation analysis, an optimal composition of 2 wt.% G, 0.25 wt.% MCMF, and 0.0625 wt.% CCMF was selected. Reinforced beam specimens were fabricated with the conductive material embedded in either the tensile (bottom) or compressive (top) region, combined with two internal architectures: diagonal infill and solid-base configuration. Four configurations were defined: Pattern 1 (bottom/diagonal), Pattern 2 (bottom/solid-base), Pattern 3 (top/diagonal), and Pattern 4 (top/solid-base). Cyclic three-point bending tests with spatially distributed electrical measurements were conducted to evaluate the electromechanical response in the elastic range. Specimens with the conductive layer located in the tensile region (Patterns 1 and 2) consistently exhibited higher gauge factors than those in the compressive region (Patterns 3 and 4). Pattern 2 exhibited the best sensing performance, with an average gauge factor of 556 and SNR of 31. Across all configurations, SNR decreased with increasing electrode spacing, with reductions of up to 31.0%, demonstrating the effect of current path length on sensing performance. Full article