Smart Materials: Synthesis, Characterization and Answers to Technological Challenges

Smart materials, also known as responsive or intelligent materials, are a class of advanced materials that can change their properties (e.g., shape, size, color, electrical conductivity) in a predictable and controlled way when exposed to external stimuli like temperature, pH, light, or magnetic fields. Their ability to react to environmental changes makes them highly promising for solving complex challenges, including those in water technology.

The synthesis of smart materials is a critical step that determines their properties and performance. Researchers can use various methods to create these materials, often with a focus on producing structures with high surface areas and specific functional groups to interact with pollutants. Key synthesis strategies include: (i) Polymerization (Creating responsive polymers and hydrogels that swell or shrink in response to changes in pH or temperature. These can be designed to capture pollutants and then release them for easy recovery); (ii) Nanomaterial synthesis (Synthesizing nanoparticles, nanotubes, and nanofibers with unique properties. For instance, creating magnetic nanoparticles allows for easy separation of contaminants from water using a magnetic field after they have been adsorbed); (iii) Composite Materials synthesis (Combining smart materials with conventional ones to enhance their performance. A common approach is incorporating photocatalytic nanoparticles (like titanium dioxide) into a polymer membrane to create a self-cleaning filter that can degrade organic pollutants under UV light; (iv) Biomimicry (Designing materials that imitate natural processes, such as using chitosan, a biopolymer from crab shells, which can be modified to adsorb heavy metals and other pollutants).

Once synthesized, smart materials must be meticulously characterized to understand their physical and chemical properties and ensure they function as intended. This process is essential for optimizing their performance and safety. Standard characterization techniques include: (i) spectroscopy (Techniques like Fourier-transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS), ultraviolet–visible spectroscopy (UV-Vis), are used to identify the chemical composition, surface functional groups of the materials), and the pressence of nanoparticles through their SPR (Surface Plasmon Resonance); (ii) microscopy (Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) provide high-resolution images of the material's morphology, and structure, e.g., pores, surface roughness); (iii) rheology and swelling tests (For hydrogels and other soft materials, these tests measure changes in their volume, viscosity, and mechanical properties in response to stimuli, confirming their "smart" behavior); (iv) adsorption and degradation studies (These are crucial for evaluating the material's performance in water treatment. They involve testing the material's capacity to remove specific pollutants and measuring the kinetics of the removal process).

Despite their potential, the widespread application of smart materials in water technology (purification, recovery of metal ions, removal of pollutants) faces several significant challenges. Addressing these issues is key to transitioning from laboratory-scale research to large-scale, real-world solutions.

Starting from these aspirations the proposed topical collection, titled "Smart materials: synthesis, characterization and answers to technological challenges," aims to delve deeply into the intersection of materials science and structural resilience. This collection will serve as a platform for cutting-edge research that goes beyond traditional materials by focusing on those with dynamic, responsive properties. We aim to highlight how these smart materials can be synthesized and characterized to create structures and systems that can adapt to and withstand various environmental and mechanical stresses.

The Collection will focus on three main pillars:

(i) Materials synthesis. Can be explore novel methods for creating smart materials with tailored properties. This includes techniques for developing polymers by functionalization with active groups, shape-memory alloys, responsive hydrogels, and other advanced composites, synthesis of nanoparticles and/or, nanocomposites tailored to increase their efficiency for different types of applications . The emphasis will be on how the synthesis process can be controlled to achieve specific functional outcomes that enhance a material's resilience for different application (photocatalysis, adsorption, water purification etc.).

(ii) Materials characterization. The collection will showcase advanced characterization techniques essential for understanding the behavior of these materials. Can feature studies that use techniques such as advanced spectroscopy, microscopy, and computational modeling to predict and analyze material performance under extreme conditions.

(iii) Applications. Not least, will address the application of these materials in solving real-world technological challenges. Submissions will focus on how smart materials can be used for: to improve the water purification, adsorption processes, heavy metals/rare earth elements recovery, heavy metals removal, photocatalysis, antimicrobial activity. The goal is to bridge the gap between fundamental research and practical engineering solutions, demonstrating the tangible impact of smart materials on morpho-structural properties.

We invite contributions that deepen our understanding of structural materials under extreme stresses. Our collection is dedicated to research that provides innovative solutions and theoretical advances relevant to structural engineering and materials science, with a particular focus on practical applications. We welcome original research articles, comprehensive reviews and detailed case studies.

This Collection will serve as a valuable resource for researchers, engineers, and policymakers involved in the analysis, and implementation of materials in structural applications, or involved in the water purification, adsorption processes, heavy metals/rare earth elements recovery, pollutant removal, photo-catalysis, microbiological role. It aims to foster collaboration and innovation in addressing the challenges posed by extreme loading scenarios through cutting-edge research and technological advancements.

Keywords: material synthesis, nanomaterial synthesis, morpho-structural characterization, adsorption, photocatalysys, heavy metals recovery, rare earth elements recovery, pollutant removal, antimicrobial activity.

This Collection supports and amplifies research related to SDG 3, SDG 6, SDG 9, and SDG 12.