Search Results (1,010)

Driven by the growing demand for sustainable materials, spent coffee grounds have emerged as a promising bio-based reinforcement in polymer composites, particularly for additive manufacturing applications. As a readily available byproduct of the coffee industry, spent coffee grounds contain cellulose, hemicellulose, lignin, proteins, and oils, making them attractive fillers for both thermoplastic and thermoset matrices. Incorporating spent coffee grounds into composites supports waste valorization, cost reduction, and environmental sustainability by transforming organic waste into functional materials. This review first examines the issue of spent coffee ground waste, addressing its environmental footprint and disposal challenges. It then explores the composition and properties of spent coffee grounds. The paper provides a comprehensive overview of composites based on spent coffee grounds for 3D printing, covering processing methods, potential applications, and current challenges in additive manufacturing. Special attention is given to the preparation and processing of these composites, including key steps such as drying, grinding, sieving, and surface modification to enhance compatibility with polymer matrices. Various additive manufacturing techniques influence the printability, processability, and mechanical performance of such composites. While spent coffee grounds offer notable sustainability advantages, challenges such as weak interfacial adhesion, moisture sensitivity, and reduced mechanical properties necessitate optimized processing conditions, surface treatments, and tailored material formulations. This review highlights recent advancements and outlines future research directions, emphasizing the need for stronger interactions between spent coffee grounds and polymer matrices, improved recyclability, and scalable additive manufacturing solutions to establish spent coffee grounds as a viable and eco-friendly alternative for 3D printing applications. Full article

Liquid metal (LM), which possesses unique material properties such as excellent flexibility, high thermal and electrical conductivities, and biocompatibility, has demonstrated broad application potential in the fields of intelligent manufacturing, flexible electronics, and biomedical engineering. This paper presents a systematic review of recent advances in multifunctional LM materials for biomimetic applications, with a focus on 3D printing, catalysis, sensing, and biomedical technologies. Through advanced 3D printing techniques—including direct writing, embedded printing, and extrusion/infiltration—LM has been effectively utilized in the fabrication of high-precision electronic components. In catalysis, LM-based catalysts exhibit superior performance in energy conversion and environmental remediation due to their high catalytic activity and selectivity. Moreover, LM has made notable progress in the development of high-performance sensors and biomedical devices, contributing significantly to the advancement of health monitoring and intelligent diagnostic and therapeutic technologies. This review aims to provide theoretical insights and technical references for further research and engineering applications of liquid metals. Full article

The fashion industry is facing increasing challenges related to textile waste and environmental pollution, driving the need for sustainable material innovations. Bacterial cellulose (BC), a biodegradable and non-polluting biomaterial, has emerged as a promising alternative for the sustainable transformation of fashion materials. Investigations into printing and dyeing techniques are expected to provide methodological frameworks for the design and functional application of BC materials, promoting their adoption and development in the fashion sector. This study, using the kombucha culture method, systematically investigated the cultivation, purification, plasticization, and drying processes of BC as a fashion material, examined its color characteristics using plant and reactive dyeing, and evaluated the effects of pattern printing and the feasibility of traditional plant pigment stencil printing, digital printing, and cyanotype printing on BC. Based on these printing and dyeing methods, digital printing combined with reactive dyeing—offering richer print effects, a wider color gamut, and higher rubbing fastness—was selected to realize the fashion design series Photosynthesis using BC as the primary material. This research contributes methodological insights into the integration of bio-based materials in fashion design and promotes the advancement of sustainable practices within the textile and apparel industries. Full article

Plant-based diets are increasingly attracting attention as they play a significant role in human health and environmental sustainability and are believed to be key components of sustainable food systems. In the present study, both pros and cons of the adoption of plant-based diets are analyzed using a bibliometric method integrated with a qualitative examination of the scientific literature. For the bibliometric study, Bibliometrix software was utilized, examining 3245 scientific articles, downloaded from the Scopus database, and printed between the years 1957 and 2025. The analyses were conducted using R software, version 4.4.1, with access to the Bibliometrix package, version 4.1. The results indicate a remarkable rise, in the last two decades, in the scholarly focus on the influence of plant-based diets on the individual’s health condition as well as the environment. Keyword co-occurrence studies and international collaborations demonstrate a dominance of research focus in both the United States and Europe, with significant contributions from the Asia–Pacific region. Furthermore, the current work offers qualitative identification of the benefits of plant diets from various perspectives like nutritional, economic, ecological, and cultural. It also explores the main dissuaders from adhering to these diets, including perceived nutritional hazards, cost perceptions, low availability, and social prohibitions. Findings emphasize that, in spite of all the barriers, plant food-based diets have a wide-ranging ability to provide tangible benefits at both the individual and population levels, and documented in the scientific literature are recommendations of expert-led education programs, economic incentives, and judiciously framed public policies to overcome these barriers and to make this transition possible towards sustainable food choices. Findings provide a comprehensive understanding of the current lines of inquiry and stage the subsequent work on how to motivate sustainability among the general population. Full article

With their rich historical, artistic, and scientific value, bronze artefacts form a significant part of our cultural heritage. These items, often found in museums around the world, offer a glimpse into past civilizations and their technological advancements. However, due to their prolonged burial and subsequent exposure to varying environmental conditions, these artefacts are prone to corrosion, necessitating meticulous preservation efforts. This review discusses the cultural significance and preservation challenges of bronze artefacts, which are emblematic of human civilization’s progression. This text highlights the historical and artistic value of ancient bronze artefacts, especially those from China, underscoring their intricate casting techniques and aesthetic richness. Despite their cultural importance, these bronze artefacts confront severe preservation issues, particularly the pervasive threat of corrosion, commonly referred to as “bronze disease”. This text also reviews the complex interplay between alloy composition, microstructure, and environmental factors that influence corrosion mechanisms. It requires an enhanced understanding of these factors to develop effective preservation strategies. This paper also emphasizes the need for innovative, eco-friendly technologies to prevent further degradation while maintaining the integrity of these precious artefacts. The applications of corrosion inhibitions, organic/inorganic coatings, as well as the newly developed strategies like the photo-induced passivation technique, 3D scanning and 3D printing techniques, and holographic projection/real and virtual technique for the direct or indirect protection and cultural transmission of the bronze artefacts were also introduced. This review concludes by underscoring the urgency of these research and development efforts to safeguard our cultural heritage for future generations. Full article

This paper analyses the role of electronic waste (E-waste) as a secondary source of critical and precious minerals, addressing the challenges and opportunities in transitioning towards a circular economy (CE) for electronics. The surging global demand for these essential materials, driven by technological advancements and renewable energy infrastructure, necessitates alternative supply strategies due to the depletion of natural reserves and the environmental degradation associated with primary mining. E-waste contains a rich concentration of valuable metals, such as gold, silver, and platinum, making its recovery a promising solution aligned with CE principles, which can mitigate environmental impacts and ensure long-term material availability. This paper examines the environmental, economic, and technological aspects of E-waste recovery, focusing on core processes such as physical and mechanical separation, pyrometallurgical, hydrometallurgical, bio-metallurgical, and electrochemical techniques. It explores innovative strategies to improve material recovery efficiency and sustainability, with consideration of evolving regulatory frameworks, technological advancements, and stakeholder engagement. The analysis highlights that e-waste, particularly printed circuit boards, can contain 40–800 times more gold than mined ore, with 1000–3000 g of gold per tonne compared to 5–10 g per tonne in traditional ores. Recovery costs using advanced E-waste recycling technologies range between $10,000–$20,000 USD per kilogram of gold, significantly lower than the $30,000–$50,000 USD per kilogram in primary mining. Globally, over 50 million tonnes of E-waste are generated annually, yet less than 20% is formally recycled. Efficient recycling methods can recover up to 95% of base and precious metals under optimized conditions. The paper argues that E-waste recycling presents a viable pathway to conserve critical raw materials, reduce environmental degradation, and enhance circular economic resilience. However, it also emphasizes persistent challenges—including high initial investment, technological limitations in developing regions, and regulatory fragmentation—that must be addressed for scalable adoption. Full article

The development of innovative and environmentally sustainable construction materials is a strategic priority in the context of the ecological transition and circular economy. Geopolymers and alkali-activated materials, derived from industrial and construction waste rich in aluminosilicates, are gaining increasing attention as low-carbon alternatives to ordinary Portland cement (OPC), which remains one of the main contributors to anthropogenic CO₂ emissions and landfill-bound construction waste. This review provides a comprehensive analysis of geopolymer-based solutions for building and architectural applications, with a particular focus on modular multilayer panels. Key aspects, such as chemical formulation, mechanical and thermal performance, durability, technological compatibility, and architectural flexibility, are critically examined. The discussion integrates considerations of disassemblability, reusability, and end-of-life scenarios, adopting a life cycle perspective to assess the circular potential of geopolymer building systems. Advanced fabrication strategies, including 3D printing and fibre reinforcement, are evaluated for their contribution to performance enhancement and material customisation. In parallel, the use of parametric modelling and digital tools such as building information modelling (BIM) coupled with life cycle assessment (LCA) enables holistic performance monitoring and optimisation throughout the design and construction process. The review also explores the emerging application of artificial intelligence (AI) and machine learning for predictive mix design and material property forecasting, identifying key trends and limitations in current research. Representative quantitative indicators demonstrate the performance and environmental potential of geopolymer systems: compressive strengths typically range from 30 to 80 MPa, with thermal conductivity values as low as 0.08–0.18 W/m·K for insulating panels. Life cycle assessments report 40–60% reductions in CO₂ emissions compared with OPC-based systems, underscoring their contribution to climate-neutral construction. Although significant progress has been made, challenges remain in terms of long-term durability, standardisation, data availability, and regulatory acceptance. Future perspectives are outlined, emphasising the need for interdisciplinary collaboration, digital integration, and performance-based codes to support the full deployment of geopolymer technologies in sustainable building and architecture. Full article

Ceramic materials have been utilized for centuries across a range of industries due to their chemical stability and porous microstructure. One prominent application is water filtration, where ceramics offer an effective medium for removing contaminants. Ceramic filters can operate under either pressure-driven or gravity-driven mechanisms. While traditional fabrication techniques, such as pottery, have been historically employed to produce ceramic filters, these methods are limited by user skills, lack of reproducibility, and geometric constraints. In contrast, modern additive manufacturing techniques provide enhanced precision, repeatability, and customization. This study employs extrusion-based 3D printing to fabricate gravity-driven ceramic filters with tailored geometries to meet specific performance requirements. The use of 3D printing allows for efficient production of uniform filters with optimized internal structures. The selected ceramic material, derived from natural sources, offers environmental compatibility, as it is both sustainable and biodegradable. The fabricated filters were evaluated for their effectiveness in treating water. The filtration tests showed significant improvements in water quality, including reduced turbidity, color, iron, manganese, and total and calcium hardness. pH increased from 6.23 to 7.26, and conductivity dropped from 7.43 mS to 4.5 mS, indicating effective ion removal. These findings highlight the potential of 3D-printed ceramic filters as an environmentally friendly and effective solution for decentralized water purification applications. Full article

This study assessed the effects of NiFe-based metal catalysts on CO₂ conversion to methane (CH₄) and carboxylic acids in microbial electrosynthesis (MES) cells. A NiFeBi alloy, when electrodeposited on a conductive bioring cathode, significantly decreased CH₄ production from 0.55 to 0.12 L (Lc d)⁻¹ while enhancing acetate production to 1.0 g (Lc d)⁻¹, indicating suppressed methanogenic activity and improved acetogenic activity. On the other hand, NiFeMn and NiFeSn catalysts showed varied effects, with NiFeSn increasing both CH₄ and acetate production and suggesting potential in promoting both chain elongation and CO₂ uptake. When these alloys were electrodeposited on a 3D-printed conductive polylactide (cPLA) lattice, the production of longer-chain carboxylic acids like butyrate and caproate increased significantly, indicating enhanced biocompatibility and nutrient delivery. The NiFeSn-coated cPLA lattice increased caproate production, which was further enhanced using an acetogenic enrichment. However, the overall throughput remained low at 0.1 g (Lc d)⁻¹. Cyclic voltammetric analysis demonstrated improved electrochemical responses with catalyst coatings, indicating better electron transfer. These findings underscore the importance of catalyst selection and cathode design in optimizing MES systems for efficient CO₂ conversion to value-added products, contributing to environmental sustainability and industrial applications. Full article

Plant-based foods have emerged as a major focus of the modern food industry as it tries to create more sustainable, environmentally friendly, and healthy products. Plant-based emulsion gels (PBEGs) can be used to provide valuable structures, textures, and functions in many plant-based food applications. For instance, they can be used as a matrix to form semi-solid plant-based meat, fish, egg, or dairy analogs, delivery systems for bioactive compounds in functional foods, and edible inks in 3D food printing. The most common PBEGs used in the food industry consist of oil droplets embedded within an aqueous phase containing a biopolymer network. However, PBEGs may also be formed from high-internal-phase emulsions (HIPEs) or aggregated emulsions. PBEGs combine the benefits of emulsions and gels, such as the ability to encapsulate both polar and non-polar functional ingredients, as well as to create desirable textural attributes. This review summarizes recent advances (2017–2025) in the development and application of PBEGs in the food sector, with a focus on their preparation methods, characterization techniques, and potential applications. The future perspectives and challenges associated with PBEGs are also discussed. Overall, this review provides a useful platform for directing future research efforts and for the practical implementation of PBEGs in plant-based food systems. Full article

The integration of 3D printing into the development of potentiometric sensors has revolutionized sensor fabrication by enabling customizable, low-cost, and rapid prototyping of analytical devices. Techniques like fused deposition modeling (FDM) and stereolithography (SLA) allow researchers to produce different sensor parts, such as electrode housings, solid contacts, reference electrodes, and even microfluidic systems. This review explains the basic principles of potentiometric sensors and shows how 3D printing helps solve problems faced in traditional sensor manufacturing. Benefits include smaller size, flexible shapes, the use of different materials in one print, and quick production of working prototypes. However, some challenges still exist—like differences between prints, limited chemical resistance of some materials, and the long-term stability of sensors in real-world conditions. This paper overviews recent examples of 3D-printed ion-selective electrodes and related components and discusses new ideas to improve their performance. It also points to future directions, such as better materials and combining different manufacturing methods. Overall, 3D printing is a powerful and growing tool for developing the next generation of potentiometric sensors for use in healthcare, environmental monitoring, and industry. Full article

Next-generation pilot suits are evolving into intelligent, adaptive platforms that integrate advanced polymeric materials, smart textiles, and on-body artificial intelligence. High-performance polymers have advanced in mechanical strength, thermal regulation, and environmental resilience, with fabrication methods like electrospinning, weaving, and 3D/4D printing enabling structural versatility and sensor integration. In particular, functional nanomaterials and hierarchical nanostructures contribute critical properties such as conductivity, flexibility, and responsiveness, forming the foundation for miniaturized sensing and integrated electronics. The integration of flexible fiber-based electronics such as biosensors, strain sensors, and energy systems enables real-time monitoring of physiological and environmental conditions. Coupled with on-body AI for multimodal data processing, autonomous decision-making, and adaptive feedback, these systems enhance pilot safety while reducing cognitive load during flight. This review places a special focus on system-level integration, where polymers and nanomaterials serve as both structural and functional components in wearable technologies. By highlighting the role of nanostructured and functional materials within intelligent textiles, we underline a potential shift toward active human–machine interfaces in aerospace applications. Future trends and advancements in self-healing materials, neuromorphic computing, and dynamic textile systems will further elevate the capabilities of intelligent pilot suits. This review discusses interdisciplinary strategies for developing pilot wearables capable of responding to real-time physiological and operational needs. Full article

An advanced anodic stripping voltammetry (ASV)-based Micro Electro Mechanical System (MEMS) sensor for cadmium (Cd) detection is presented in this study, which is cost-effective and efficient for in situ water monitoring, providing a crucial early warning mechanism, streamlining environmental monitoring, and facilitating timely intervention to safeguard public health and environmental safety. The rationale behind this work is to address the critical need for an in situ monitoring system for cadmium (Cd) in freshwater sources, particularly those adjacent to agricultural fields. Cd(II) is a highly toxic heavy metal that poses a significant threat to agricultural ecosystems and human health due to its rapid bioaccumulation in plants and subsequent entry into the food chain. The developed analytic device is composed of a commercial mercury salt-modified graphite screen-printed electrode (SPE) with a custom-designed innovative polydimethylsiloxane (PDMS) flow detection cell. The flow cell was prototyped using 3D printing and replica moulding, with its design and performance validated through COMSOL Multiphysics simulations to optimize inflow conditions and ensure maximum analyte dispersion on the working electrode surface. Chemical detection was performed using square wave voltammetry, demonstrating a linear response for Cd(II) concentrations of 0 to 20 µg/L. The system exhibited robust analytical performance, enabling 25–30 daily analyses with consistent sensitivity within the Limit of Detection (LoD) set by the law of 3 µg/L. Full article

Additive manufacturing (AM), commonly known as 3D printing, has emerged as a transformative technology across various industries due to its potential for design flexibility, material efficiency, and reduced production lead times. As global attention increasingly shifts toward environmental sustainability, there is a growing need to evaluate the ecological implications and opportunities associated with AM. This comprehensive review explores the current state of sustainable and green additive manufacturing (SGAM) technologies and practices, highlighting innovations that reduce energy consumption, minimize material waste, and incorporate renewable or recyclable materials. This study focuses on the utilization of recyclable thermoplastics combined with biodegradable polymers, exploring sustainable source materials, cold fabrication techniques, and cyclic lifecycle strategies integrated with renewable energy systems. Despite its potential, SGAM faces key challenges such as material compatibility, scalability of manufacturing processes, mechanical property optimization, and the need for standardized production protocols. Nevertheless, this work finds that SGAM devices are effective in minimizing environmental impact across the entire manufacturing process, aligning with predominant research trends that emphasize strategic predictive models to guide future developments in AM system implementation. The review concludes with future directions and research opportunities to enhance the environmental performance of AM technologies, ultimately contributing to a more sustainable manufacturing landscape. Full article

Natural disasters are increasing in frequency and intensity, causing escalating humanitarian crises and complex housing challenges globally. Traditional post-disaster housing solutions often fall short, being slow, costly, and ill-adapted to specific community needs. This study addresses these limitations by proposing an innovative, technology-driven model for post-disaster housing that integrates parametric design with 3D printing. The objective is to develop a flexible and adaptable system capable of providing both immediate temporary shelter and evolving permanent housing solutions. In this study, the methodology of the proposed model for post-disaster housing solutions is structured around three main phases: the development of the theoretical framework, the parametric design process, and the implementation phase. In the first phase, a comprehensive literature review and conceptual analyses were conducted to examine the concept of disaster, post-disaster housing approaches, and advanced technologies, thereby establishing the conceptual foundation of the model. In the second phase, parametric modeling was carried out for a modular system using algorithmic design tools such as Grasshopper; the model’s applicability across various scales and its flexibility were analyzed. In the final phase, material selection and digital prototyping of the gridal system were undertaken using 3D printing technology to evaluate the model’s feasibility for rapid on-site production, assembly, and disassembly. The model prioritizes user participation, modularity, and configurability to ensure rapid response and socio-cultural sensitivity. Findings indicate that this integrated approach offers substantial benefits, including accelerated construction, reduced labor and material waste, enhanced design flexibility, and the use of local, sustainable materials. This research highlights the transformative potential of advanced manufacturing in providing resilient, user-centered, and environmentally sustainable post-disaster housing, advocating for governmental financial support to overcome adoption barriers and foster broader implementation. Full article