Cellulose nanofibers (CNFs), cellulose nanomaterials (CNMs), and cellulose-based composites represent a convergence of material science, sustainability, and advanced engineering, paving the way for innovative and eco-friendly materials. This paper presents a comprehensive review of these materials, encompassing their extraction, preparation methods, properties, applications, and future directions. The manufacturing of CNFs and CNMs leverages diverse techniques—chemical, mechanical, and enzymatic—with each offering distinct advantages in tailoring material characteristics to meet specific needs. Strategies for functionalization and surface modification are detailed, highlighting their role in enhancing the properties of CNFs and composites while addressing challenges in scaling production to industrial levels. The structural, mechanical, thermal, optical, electrical, and biocompatibility properties of CNFs, CNMs, and their composites are explored, underscoring their versatility for applications across various industries. Cellulose-based composites, in particular, demonstrate exceptional tunable properties for specific uses, although achieving uniform dispersion remains a key technical hurdle. These materials have applications in packaging, automotive, aerospace, biomedical devices, energy storage, and environmental remediation. Emerging research trends emphasize the integration of CNFs and CNMs with advanced manufacturing technologies, promoting sustainable practices and life cycle considerations while advancing their commercialization potential. This rapidly evolving field holds immense promise for addressing global challenges by creating high-performance, and sustainable materials. This review is crucial in advancing the understanding of cellulose nanofibers, nanomaterials, and cellulose-based composites, providing valuable insights that will drive the development of sustainable, high-performance materials for a wide range of applications, ultimately addressing key global challenges.

Electronic waste (e-waste) is the fastest-growing waste stream on the planet, yet it remains critically under-addressed in global waste management and recycling efforts. The rapid pace of technological advancement has led to increased consumption of electronic devices, many of which are challenging and costly to recycle efficiently. Insufficient infrastructure for e-waste recycling has resulted in large quantities being exported to countries with minimal waste management capabilities. In these regions, waste is often processed manually, exposing workers to hazardous materials and toxic elements commonly found in electronic components, leading to serious health risks. E-waste consists primarily of fibrous composite materials and plastics mixed with valuable metals and reusable components. While metals are often recovered, the remaining materials are typically discarded, contributing to significant environmental harm. Addressing e-waste challenges requires more than just technological solutions. In the United States, limited policies promote large-scale reuse and recycling practices, particularly among corporations. To build a sustainable approach, a combination of next-generation, cost-effective chemical recycling technologies and forward-thinking policy reforms will be essential for the effective management and reduction of e-waste. This paper explores the global generation and composition of e-waste, highlighting its environmental and health impacts due to improper handling and disposal. It reviews current and emerging recycling technologies while examining the challenges and opportunities in e-waste management. Finally, it discusses sustainable solutions and future directions for improving e-waste recycling through innovative technologies and policy reforms, concluding with recommendations for a circular economy approach.

Tribological processes in extreme environments pose serious material challenges, requiring coatings that resist both wear and corrosion. This review summarizes recent advances in protective coatings engineered for extreme environments such as high temperatures, chemically aggressive media, and high-pressure and abrasive domains, as well as cryogenic and space applications. A comprehensive overview of promising coating materials is provided, including ceramic-based coatings, metallic and alloy coatings, and polymer and composite systems, as well as nanostructured and multilayered architectures. These materials are deployed using advanced coating technologies such as thermal spraying (plasma spray, high-velocity oxygen fuel (HVOF), and cold spray), chemical and physical vapor deposition (CVD and PVD), electrochemical methods (electrodeposition), additive manufacturing, and in situ coating approaches. Key degradation mechanisms such as adhesive and abrasive wear, oxidation, hot corrosion, stress corrosion cracking, and tribocorrosion are examined with coating performance. The review also explores application-specific needs in aerospace, marine, energy, biomedical, and mining sectors operating in aggressive physiological environments. Emerging trends in the field are highlighted, including self-healing and smart coatings, environmentally friendly coating technologies, functionally graded and nanostructured coatings, and the integration of machine learning in coating design and optimization. Finally, the review addresses broader considerations such as scalability, cost-effectiveness, long-term durability, maintenance requirements, and environmental regulations. This comprehensive analysis aims to synthesize current knowledge while identifying future directions for innovation in protective coatings for extreme environments.

Solid-state lithium-ion batteries are gaining attention as a promising alternative to traditional lithium-ion batteries. By utilizing a solid electrolyte instead of a liquid, these batteries offer the potential for enhanced safety, higher energy density, and longer life cycles. The solid electrolyte typically consists of a polymer matrix integrated with ceramic fillers, which can significantly boost ionic conductivity. Research efforts are currently focused on advancing materials for the battery’s three primary components: the electrolyte, anode, and cathode. Furthermore, innovative strategies are being developed to optimize the interfaces between these components, addressing key challenges in performance and durability. Cutting-edge manufacturing techniques are also being explored to improve production efficiency and reduce costs. With continued advancements, solid-state lithium-ion batteries are poised to become integral to next-generation technologies, including electric vehicles and wearable electronics.

This review provides a critical overview of MXenes, an innovative class of 2D transition metal carbides, nitrides, and carbonitrides, emphasizing their synthesis, properties, and application potential. We systematically examine synthesis methods, contrasting top-down approaches with emerging green alternatives and bottom-up techniques, evaluating each in terms of scalability, cost, and environmental impact. This paper highlights MXenes’ unique characteristics, including high electrical conductivity, tunable surface chemistry, and structural versatility, which enable their use in energy storage, environmental remediation, biomedicine, and electromagnetic shielding. Key challenges such as oxidative instability, interfacial incompatibility, and hazardous etching processes are critically discussed. We identify future research priorities, including defect-engineered stabilization, AI-optimized manufacturing, and advanced integration protocols to bridge the gap between laboratory breakthroughs and industrial deployment. By integrating these insights, this review offers a roadmap for advancing MXenes from laboratory innovation to industrial application.

Battery recycling has become increasingly crucial in mitigating environmental pollution and conserving valuable resources. As demand for battery-powered devices rises across industries like automotive, electronics, and renewable energy, efficient recycling is essential. Traditional recycling methods, often reliant on manual labor, suffer from inefficiencies and environmental harm. However, recent artificial intelligence (AI) advancements offer promising solutions to these challenges. This paper reviews the latest developments in AI applications for battery recycling, focusing on methodologies, challenges, and future directions. AI technologies, particularly machine learning and deep learning models, are revolutionizing battery sorting, classification, and disassembly processes. AI-powered systems enhance efficiency by automating tasks such as battery identification, material characterization, and robotic disassembly, reducing human error and occupational hazards. Additionally, integrating AI with advanced sensing technologies like computer vision, spectroscopy, and X-ray imaging allows for precise material characterization and real-time monitoring, optimizing recycling strategies and material recovery rates. Despite these advancements, data quality, scalability, and regulatory compliance must be addressed to realize AI’s full potential in battery recycling. Collaborative efforts across interdisciplinary domains are essential to develop robust, scalable AI-driven recycling solutions, paving the way for a sustainable, circular economy in battery materials.