Search Results (2,781)

Photovoltaic (PV) energy conversion is expected to contribute to the creation of a clean energy society. For realizing such a vision, various developments such as high-efficiency, low-cost and highly reliable materials, solar cells, modules and systems are necessary. Cooperation with storage batteries is also very important for regulation and self-consumption. The creation of new applications such as building integrated PV, vehicle integrated PV, agriculture PV and floating PV is also very important for further installation of PV and reducing CO₂ emission. The sustainability of material consumption, along with reducing, reusing and recycling are also key issues for widespread deployment of PV. This paper provides an overview of the current status of photovoltaics and discusses future directions for photovoltaics from the view-points of high-efficiency, low-cost, reliability, and importance of integrated photovoltaics and sustainability. Full article

Electrochemical deposition of silicon is considered a promising alternative to conventional high-temperature and high-emission methods of silicon production. This review analyzes the current state of research on electrolyte systems used for silicon electrodeposition, with a particular focus on their potential for industrial-scale application. These systems are evaluated based on key characteristics relevant to such implementation, including silicon precursor solubility, electrical conductivity, applicable current density, and behavior under process conditions. The study evaluates fluoride-based, chloride-based, mixed halide, and organic electrolyte systems based on key criteria, including conductivity, chemical stability, silicon precursor solubility, temperature range, and ease of product purification. Fluoride-based melts offer high current densities (up to 2 A/cm²) and effective SiO₂ dissolution but operate at high temperatures (550–1300 °C) and suffer from hygroscopicity. Chloride systems exhibit lower operating temperatures (300–1000 °C) and better water solubility but lack compatibility with common silicon sources. Mixed fluoride–chloride electrolytes emerge as the most promising option, combining high performance with improved practicality; they operate at 600–850 °C and current densities up to ~1.5 A/cm². Additional focus is placed on the impact of substrate materials and on unresolved questions related to reaction reversibility, kinetic mechanisms, and the influence of electrolyte composition. The review concludes that further fundamental studies are needed to optimize electrolyte design and enable the transition from laboratory-scale research to industrial implementation. Full article

Advances in OLED display technology have increased the demand for high-performance luminescent materials, yet efficient red emitters with narrow emission spectra remain rare. Here, two new polycyclic compounds (O-QA and S-QA) are designed by incorporating oxygen/sulfur into a carbonyl/nitrogen skeleton. Photophysical and theoretical studies reveal their hybridized local and charge-transfer state characteristics. In toluene, O-QA and S-QA show photoluminescence peaks at 586/579 nm with narrow emission spectra, while doped films exhibit strong red emissions peaking at 598/600 nm with high PL quantum yields of 67%/60%. The OLEDs using these emitters achieve red electroluminescence (EL) peaks at 598/602 nm, and attain maximum external quantum efficiencies of 7.36%/14.54%. This work may provide guidance for the development of narrow-spectrum red emitters based on carbonyl/nitrogen frameworks. Full article

Coal gangue, an industrial byproduct of coal mining, was traditionally utilized in concrete production as a coarse aggregate. However, recent advancements have expanded its application by processing it into fine powder for use as a supplementary cementitious material (SCM), partially replacing cement. This approach not only enhances the sustainable reuse of coal gangue but also contributes to reducing cement consumption and associated carbon emissions. Nevertheless, the incorporation of coal gangue may adversely affect the mechanical strength and long-term durability of concrete. This review provides a systematic analysis of recent research on coal gangue-modified concrete. It begins by classifying the functional roles of coal gangue in concrete mixtures, followed by a critical evaluation of its impact on mechanical properties and durability—both as an aggregate an as a mineral admixture. When 30% of the aggregate is replaced with activated coal gangue, the average compressive strength of concrete increases by 15%. When coal gangue replaces less than 20% of the cement, the compressive strength of concrete can reach 95% of the reference strength. Second, the review evaluates the modification effects of various mineral admixtures, elucidating their mechanisms for enhancing mechanical properties and durability in coal gangue-based concrete. Finally, it examines the underlying interaction mechanisms between these admixtures and coal gangue, while identifying key future research directions for optimizing admixture formulations. By providing a comprehensive and critical analysis of current research, this paper serves as a valuable reference for developing high-performance coal gangue concrete with increased substitution rates and tailored admixture systems. Ultimately, this work advances the design of sustainable, low-cement concrete using industrial byproducts, enabling performance-driven applications and supporting next-generation green construction materials. Full article

Noise barriers are commonly used to reduce the adverse effects of traffic noise in both urban and suburban settings. While conventional systems constructed from concrete and steel provide reliable acoustic and structural performance, they raise sustainability concerns due to high embodied energy and carbon emissions. Glued-laminated (glulam) timber has emerged as a sustainable alternative, offering a reduced carbon footprint, aesthetic appeal, and effective acoustic performance. However, the crashworthiness of timber-based noise wall systems remains under investigated, particularly with respect to the safety criteria established in the 2016 edition of the American Association of State Highway and Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH). This study presents the full-scale crash testing and evaluation of glulam rubrail and noise wall systems under MASH Test Level 3 (TL-3) impact conditions. Building on a previously tested system compliant with National Cooperative Highway Research Program (NCHRP) Report 350, modifications were made to increase rubrail dimensions to meet higher lateral design loads. Three full-scale vehicle crash tests were conducted using 1100C and 2270P vehicles at 100 km/h and 25 degrees, covering both front- and back-mounted wall configurations. All tested systems demonstrated acceptable structural performance, effective vehicle redirection, and compliance with MASH 2016 occupant risk criteria. There was no penetration or potential for debris intrusion into the occupant compartment, and all measured occupant risk values remained well below allowable thresholds. Minimal damage to structural components was observed. The results confirm that the modified glulam noise wall system meets current impact safety standards and is suitable for use along high-speed roadways. This work supports the integration of sustainable materials into roadside safety infrastructure without compromising crash performance. Full article

Emission reduction in the steel industry has become a challenge due to its high environmental impact, being responsible for 7% of anthropogenic emissions. Several strategies have emerged to mitigate its carbon footprint; among them, carbon capture and storage (CCS) has become a promising long-term alternative. In this work, two low-energy mineral carbonation methods—aqueous and semi-dry—were considered for the processing of a commercial slag derived from electric arc furnace (EAF) steelmaking. These methods were selected for their lower energy and water requirements, as they operate at atmospheric pressure, moderate temperatures, and involve minimal use of chemical additives. Variables such as temperature, time, and the use of sodium carbonate were analysed. Aqueous carbonation favoured a higher carbonate precipitation compared to semi-dry carbonation. However, this process also led to an increase in microcracks on the surface. With respect to the theoretical sequestration rate, carbon dioxide fixation was relatively low, reaching values close to 3%. Nevertheless, when evaluating the overall impact of carbonation on the final material properties, the results suggest that low-consumption mineral carbonation, particularly under simplified operational conditions, is a promising strategy for industrial application. In addition to contributing to CO₂ sequestration, this process improves physical properties, which reinforces its potential in carbon capture and storage strategies. Full article

As operational emissions decrease due to improved energy efficiency, reducing embodied carbon in buildings has become increasingly important. Life cycle assessment (LCA) is a widely used method to quantify these impacts. However, its implementation often remains data-intensive and time-consuming due to the need for detailed material inventories. This study analyzes 100 LCA reports submitted for G-SEED certification in South Korea to identify a core set of construction materials that accounts for most of the total material mass. Unlike previous approaches that relied on 99% cumulative mass thresholds, this study introduces a function-based classification framework considering both material roles and environmental impact intensity, offering a novel pathway for simplifying LCA. The findings reveal 12 key material categories, such as ready-mixed concrete, cement-based products, structural steel, wood, and interior finishes, that dominate embodied carbon contributions, with concrete alone composing over 85% of the total mass based on the analyzed G-SEED dataset. A material classification framework is then developed, organized by functional role and carbon impact. By focusing on these high-impact materials, future LCA efforts can be significantly streamlined without compromising accuracy. This approach offers data-driven guidance for LCA practitioners, designers, and green building certification bodies aiming for efficient and reliable carbon assessments. Full article

This study aimed to evaluate the penetration and bonding performance of three restorative materials—high-viscosity glass ionomer cement (Riva Self Cure HV), resin-modified glass ionomer cement (Riva Light Cure) and a bioactive resin (Activa BioActive Restorative™)—in the healthy and carious dentine of permanent molars. Forty extracted human molars with sound or decayed dentine were restored following standardised protocols and subsequently divided into slices. So, twenty-four samples were used for each group (sound and carious dentine) for interface analysis using confocal laser scanning microscopy, field emission scanning electron microscopy and energy dispersive X-ray spectroscopy, and another eight simples were used for each group (sound and carious dentine) for Vickers microhardness testing. Results showed that both glass ionomer cements achieved consistent chemical bonding in healthy dentine and demonstrated better interfacial adaptation compared to carious dentine, where partially demineralised areas showed weaker bonding. The bioactive resin exhibited good adhesion in sound dentine due to the adhesive system but showed poorer interaction in decayed dentine with signs of interfacial separation. Elemental analysis revealed similar compositions among materials, with no significant differences in material concentrations among the ionomers, while there were significant differences with the other materials. On the other hand, some variations were observed in the sulphur, fluoride and strontium content depending on dentine condition. Microhardness values were higher in healthy dentine than in carious dentine for all materials (p < 0.001), except the high-viscosity glass ionomer, which maintained stable hardness in both substrates (36.33 ± 6.23 VHN vs. 34.56 ± 4.31 VHN; p = 0.605). These findings highlight the relevance of material selection and dentine condition in minimally invasive restorative dentistry. Full article

This study addresses this gap by proposing a multilevel fuzzy evaluation model combined with an analytic hierarchy process (AHP) to quantify the greenness of furniture products across their entire lifecycle. Focusing on an office desk as a case study, we developed an indicator system encompassing environmental attributes, resource efficiency, energy consumption, economic costs, and quality performance. Weighting results revealed that environmental attributes (27.2%) and resource efficiency (27.2%) dominated the greenness evaluation, with material recycling rate (33.5%) and solid waste pollution (24.3%) as critical sub-indicators. The prototype achieved a moderate greenness score of 70.38/100, highlighting optimization potential in renewable material adoption (10% current rate) and modular design for disassembly. Mechanically recycled materials could reduce lifecycle emissions by 18–25% in key categories. The model demonstrates scalability for diverse furniture types and informs policy-making by prioritizing high-impact areas such as toxic material reduction and energy-efficient manufacturing, thus amplifying its global and interdisciplinary multiplier effects. Full article

Actions related to reducing CO₂ emissions have led to the development of technologies using raw materials in the form of broadly understood biomass as CO₂-neutral fuels. There has been a rapid development of pyrolysis processes (carbonization, dry distillation) of various types of biomass toward the production of biochar for industrial applications. Particularly high hopes are associated with the use of biochar as a substitute for fossil fuel in energy-intensive sectors of the economy, especially the metallurgical and steel industries. This paper characterizes the current state and potential for biochar application, using the iron and steel industry as a case study. The analysis focuses primarily on the characteristics of biochar production and its industrial application potential. The characterization includes the diversity of biomass feedstocks, processing methods, and reactor types, the influence of operational parameters on biochar yield, as well as the properties and applications of biochar. As part of the analysis of biomass use potential in the iron and steel industry, the study reviews the current levels of coal substitution achieved at the laboratory scale and presents examples of biochar implementation in existing industrial facilities. In addition, key factors limiting the feasibility of coal substitution in the iron and steel industry are identified. The summary includes the main directions for further research aimed at increasing the use of biochar in industry. Full article

The environmental impact of cement production is strongly associated with the high clinker content and its corresponding CO₂ emissions. This study examines the performance of low-emission cement mortars incorporating supplementary cementitious materials (SCMs), such as ground granulated blast-furnace slag (GGBFS) and fly ash, which partially replace clinker and contribute to CO₂ reduction. Six cement types (CEM I, CEM II/B-V, CEM II/B-S, CEM III/A, CEM V/A (S-V), and CEM V/B (S-V)) were assessed in 104 mortar formulations using a polycarboxylate-based superplasticizer, under varied curing temperatures (10 °C, 20 °C, 29 °C, and 33 °C). The present study is an experimental analysis of the impact of different plasticising and superplasticising admixtures on the demand for admixtures to achieve high flowability and low air content in cement-standardised mortar for admixture testing. PN-EN 480-1. The results indicate that mortars containing CEM III/A and CEM V/B (S-V) exhibited compressive strengths comparable to or superior to CEM I at 28 days, with strength gains exceeding 60 MPa at 20 °C. Workability retention at elevated temperatures was most effective in slag-rich cements. The plasticizing efficiency of the admixture decreased at temperatures above 29 °C, especially in fly ash-rich systems. The incorporation of SCMs resulted in an estimated reduction of up to 60% in clinker, with a corresponding potential decrease in CO₂ emissions of 35–45%. These findings demonstrate the technical feasibility of using low-clinker, superplasticized mortars in varying thermal environments, supporting the advancement of sustainable cementitious systems. Full article

The present study explores the sustainable potential of volcanic ash sourced from the active Sakurajima volcano (Japan) as an eco-friendly alternative to Portland cement—a binder known for its high carbon emissions—in concrete and mortar production. The abundant pyroclastic material, currently a waste burden for the residents of Sakurajima and the Kagoshima Bay region, presents a unique opportunity for valorization in line with circular economy principles. Rather than treating this ash as a disposal problem, the research investigates its transformation into a valuable supplementary cementitious material (SCM), contributing to more sustainable construction practices. The investigation focused on the material characterization of the ash (including chemical composition, morphology, and PSD) and its pozzolanic activity index, which is a key indicator of its suitability as a cement replacement. Mortars were prepared with 25% of the commercial binder replaced by volcanic ash—both in its raw form and after mechanical activation—and tested for compressive strength after 28 and 90 days of water curing. Additional assessments included workability of the fresh mix (flow table test), apparent density, and flexural strength of the hardened composites. Tests results showed that the applied volcanic ash did not influence the workability of the mix and showed negligible effect on the apparent density (changes of up to 3.3%), although the mechanical strength was deteriorated (decrease by 15–33% after 7 days, and by 25–26% after 28 days). However, further investigation revealed that the simple mechanical grinding significantly enhances the pozzolanic reactivity of Sakurajima ash. The ground ash achieved a 28-day activity index of 81%, surpassing the 75% threshold set by EN 197-1 and EN 450-1 standards for type II mineral additives. These findings underscore the potential for producing low-carbon mortars and concretes using locally sourced volcanic ash, supporting both emissions reduction and sustainable resource management in construction. Full article

This study evaluated the feasibility of reusing abandoned copper mine tailings (Cu tailings) as a precursor in the production of fly-ash-based alkali-activated materials (FA-AAMs). Two formulations were developed by combining FA and Cu tailings with a mixture of sodium silicate and sodium hydroxide as alkaline activators at room temperature (20 °C). Formulation G1 consisted of 70% Cu tailings and 30% fly ash (FA), whereas G2 included the same composition with an additional 15% ordinary Portland cement (OPC). The materials were characterized using X-ray fluorescence (XRF), -X-ray diffraction (XRD), field emission scanning electron microscopy with energy-dispersive spectroscopy (FESEM-EDS), and particle size analysis. While FA exhibited a high amorphous content (64.4%), Cu tailings were largely crystalline and acted as inert fillers. After 120 days of curing, average compressive strength reached 24 MPa for G1 and 41 MPa for G2, with the latter showing improved performance due to synergistic effects of geopolymerization and OPC hydration. Porosity measurements revealed a denser microstructure in G2 (35%) compared to G1 (52%). Leaching tests confirmed the immobilization of hazardous elements, with arsenic concentrations decreasing over time and remaining below regulatory limits. Despite extended setting times (24 h for G1 and 18 h for G2) and the appearance of surface efflorescence, both systems demonstrated good chemical stability and long-term performance. The results support the use of Cu tailings in FA-AAMs as a sustainable strategy for waste valorization, enabling their application in non-structural and moderate-load-bearing construction components or waste encapsulation units. This approach contributes to circular economy goals while reducing the environmental footprint associated with traditional cementitious systems. Full article

The giant squid (Dosidicus gigas) is an abundant marine species with high protein content, making it a promising resource for the food and biomaterial industries. This study aimed to investigate the effect of temperature (25–100 °C) on the structural changes in sarcoplasmic, myofibrillar, and stromal proteins isolated from squid mantle. Fourier-transform infrared spectroscopy (FT-IR) and circular dichroism (CD) were employed to monitor modifications in secondary structure, while field emission scanning electron microscopy (FE-SEM) was used to examine morphological characteristics. The FT-IR analysis revealed temperature-induced transitions in amide I, II, and A bands, indicating unfolding and aggregation processes, particularly in myofibrillar and stromal proteins. CD results confirmed a loss of α-helix content and an increase in β-sheet structures with rising temperature, especially above 60 °C, suggesting progressive denaturation. FE-SEM micrographs illustrated clear morphological differences: sarcoplasmic proteins displayed smooth, amorphous structures; myofibrillar proteins exhibited fibrous, porous networks; and stromal proteins presented dense and layered morphologies. These findings highlight the different thermal sensitivities and structural behaviors of squid muscle proteins and provide insight into their potential functional applications in thermally processed foods and bio-based materials. Full article

Human activities undoubtedly increase greenhouse gases (GHG), negatively influencing global climate change. The building and construction sector uses at least 40% of the total energy consumption and produces the same percentage of GHG emissions. Therefore, the development of sustainable building materials is a crucial key factor for environmental protection. The study contributes to the development of bio-based façade materials using available raw biomass like wheat straw, grey alder, and softwood (a mix of spruce and pine), to promote reduced emissions of CO₂. Two technologies were used to produce high-density particleboards based on (1) steam explosion treatment and (2) the addition of bio-based suberinic acids as a binder. In addition to the biomass species and board type, the influence of conventional and mold hot-pressing was investigated on produced board properties: density, thickness swelling, modules of rupture and elasticity in bending, and internal bonding. The obtained particleboards demonstrate significant differences in terms of the tested properties depending on all variable factors. The best performance, in terms of physical–mechanical properties, was achieved by the conventionally hot-pressed board of steam-exploded grey alder particles, being influenced by the highest density (1380 kg/m³). Mold hot-pressing in most cases resulted in decreased performance of obtained boards. Full article