Development Of Sustainable Materials Research Articles

Review of Geopolymer Nanocomposites: Novel Materials for Sustainable Development.

The demand for geopolymer materials is constantly growing. This, in turn, translates into an increasing number of studies aimed at developing new approaches to the methodology of geopolymer synthesis. The range of potential applications of geopolymers can be increased by improving the properties of the components. Future directions of studies on geopolymer materials aim at developing geopolymers showing excellent mechanical properties but also demonstrating significant improvement in thermal, magnetic, or sorption characteristics. Additionally, the current efforts focus not only on the materials' properties but also on obtaining them as a result of environment-friendly approaches performed in line with circular economy assumptions. Scientists look for smart and economical solutions such that a small amount of the modifier will translate into a significant improvement in functional properties. Thus, special attention is paid to the application of nanomaterials. This article presents selected nanoparticles incorporated into geopolymer matrices, including carbon nanotubes, graphene, nanosilica, and titanium dioxide. The review was prepared employing scientific databases, with particular attention given to studies on geopolymer nanocomposites. The purpose of this review article is to discuss geopolymer nanocomposites in the context of a sustainable development approach. Importantly, the main focus is on the influence of these nanomaterials on the physicochemical properties of geopolymer nanocomposites. Such a combination of geopolymer technology and nanotechnology seems to be promising in terms of preparation of nanocomposites with a variety of potential uses.

The Influence of Blast Furnace Slag on Cement Concrete Road by Microstructure Characterization and Assessment of Physical-Mechanical Resistances at 150/480 Days.

The results presented in this paper on the appropriateness of using of blast furnace slag (BFS) in the composition of roads make an original contribution to the development of sustainable materials with the aim to reduce the carbon footprint and the consumption of natural resources. The novelty of this work consists of determining the optimal percentage of BSF in road concrete, in order to: increase mechanical resistances, reduce contractions in the hardening process, and ensure increased corrosion resistances, even superior to classic cement-based mixtures. Thus, the physical-mechanical characteristics and the microstructure of some road concretes were studied in the laboratory for three different recipes. We kept the same amount of ground granulated blast furnace slag (GGBS) as a substitute for Portland cement, respectively three percentages of 20%, 40%, 60% air-cooled blast furnace slag (ACBFS) and crushed as sand substitute from now on called S54/20, S54/40, S54/60. Drying shrinkage, mechanical resistances, carbonation-induced corrosion, microstructure characterization of hardened concretes, and degree of crystallinity by SEM and XRD measurements were analyzed after a longer curing period of 150/480 days. The obtained results on the three BSF mixtures indicated a reduction of drying shrinkage and implicitly increased the tensile resistance by bending to 150 days well above the level of the blank composition. The degree of crystallinity and the content of the majority phases of the mineralogical compounds, albites, quartz, and tobermorite out of the three BSF samples justifies the increase in the compressive strengths at the age of 480 days in comparison with the test samples. Scanning electron microscope (SEM) and X-ray diffraction measurements showed the highest compactness and lowest portlandite crystal content for the S54/20 slag composite. Future research concerns are the realization of experimental sections in situ, the study of the influence of BFS on the elasticity module of road concrete, and the opportunity to use other green materials that can contribute to the reduction of the carbon footprint, keeping the physical and mechanical properties of road concrete at a high level.

Photogrammetry of Ultrafast Excited-State Intramolecular Proton Transfer Pathways in the Fungal Pigment Draconin Red.

Proton transfer processes of organic molecules are key to charge transport and photoprotection in biological systems. Among them, excited-state intramolecular proton transfer (ESIPT) reactions are characterized by quick and efficient charge transfer within a molecule, resulting in ultrafast proton motions. The ESIPT-facilitated interconversion between two tautomers (PS and PA) comprising the tree fungal pigment Draconin Red in solution was investigated using a combination of targeted femtosecond transient absorption (fs-TA) and excited-state femtosecond stimulated Raman spectroscopy (ES-FSRS) measurements. Transient intensity (population and polarizability) and frequency (structural and cooling) dynamics of -COH rocking and -C=C, -C=O stretching modes following directed stimulation of each tautomer elucidate the excitation-dependent relaxation pathways, particularly the bidirectional ESIPT progression out of the Franck-Condon region to the lower-lying excited state, of the intrinsically heterogeneous chromophore in dichloromethane solvent. A characteristic overall excited-state PS-to-PA transition on the picosecond timescale leads to a unique "W"-shaped excited-state Raman intensity pattern due to dynamic resonance enhancement with the Raman pump-probe pulse pair. The ability to utilize quantum mechanics calculations in conjunction with steady-state electronic absorption and emission spectra to induce disparate excited-state populations in an inhomogeneous mixture of similar tautomers has broad implications for the modeling of potential energy surfaces and delineation of reaction mechanisms in naturally occurring chromophores. Such fundamental insights afforded by in-depth analysis of ultrafast spectroscopic datasets are also beneficial for future development of sustainable materials and optoelectronics.

Benzoxazine-grafted-chitosan biopolymer films with inherent disulfide linkage: Antimicrobial properties

Synthesis and fabrication of naturally sourced biopolymers, especially chitosan, grafted with renewable small molecules have recently attracted attention as efficient antimicrobial agents and are highly desired for sustainable material development. Advantageous inherent functionalities in biobased benzoxazine extend the possibility of crosslinking with chitosan which holds immense potential. Herein, a low-temperature, greener facile methodology is adopted for the covalent confinement of benzoxazine monomers bearing aldehyde and disulfide linkages within chitosan to form benzoxazine-grafted-chitosan copolymer films. The association of benzoxazine as Schiff base, hydrogen bonding, and ring-opened structures enabled the exfoliation of chitosan galleries, and such host-guest mediated interactions demonstrated outstanding properties like hydrophobicity, good thermal, and solution stability due to the synergistic effects. Furthermore, the structures empowered excellent bactericidal properties against both E. coli and S. aureus as investigated by GSH loss, live/dead fluorescence microscopy, and morphological alteration on the cell surface by SEM. The work provides the benefits of disulfide-linked benzoxazines on chitosan, offering a promising avenue for general and eco-friendly usage in wound–healing and packaging material.

Progress in Sustainable Polymers from Biological Matter

The increasing consumption of nonrenewable materials urgently calls for the design and fabrication of sustainable alternatives. New generations of materials should be derived from renewable sources, processed using environmentally friendly methods, and designed considering their full life cycle, especially their end-of-life fate. Here, we review recent advances in developing sustainable polymers from biological matter (biomatter), including progress in the extraction and utilization of bioderived monomers and polymers, as well as the emergence of polymers produced directly from unprocessed biomatter (entire cells or tissues). We also discuss applications of sustainable polymers in bioplastics, biocomposites, and cementitious biomaterials, with emphasis on relating their performance to underlying fundamental mechanisms. Finally, we provide a future outlook for sustainable material development, highlighting the need for more accurate and accessible tools for assessing life-cycle impacts and socioeconomic challenges as this field advances.

Studies on the mechanical and durability performance of textile reinforced geopolymer concrete beams

The steel reinforcements used in structural elements are prone to corrosion due to adverse environmental effects. Hence, in recent years, the development of sustainable materials to replace steel reinforcement in concrete has been under research. In this paper, the mechanical and durability characteristics of Geopolymer Concrete (GC) and Epoxy-coated Carbon (EC) yarn against chemical attack were investigated. Tension tests were conducted on EC yarns immersed in acid, sulfate, marine water, and alkaline solution over an exposure period of 1 year. The test results reveal that better durability was achieved for GC specimens compared to cement concrete (CC) specimens in terms of water absorption, acid resistance, sulfate resistance, marine water attack, and chloride diffusion. Compressive strength and flexural strength obtained were 2.6–7.7 times and 1.65–2.36 times higher in GC compared to CC after immersion in various chemical solutions for 6 months. The chemical resistance of EC yarns over an exposure period of 1 year was measured with respect to loss in tensile strength and the reduction in strength was obtained as 29.6% for EC yarns immersed in acid solution, 14.71% in sulfate solution, 7.06% in alkali, and 3.82% in marine water. The study also investigated the flexural behavior of Textile Reinforced Geopolymer Concrete (TRGC) beams (100 × 100 × 500 mm) subjected to monotonic loading. The effectiveness of textile yarn spacing and the number of carbon textile layers to improve the load-bearing behavior of GC beams were evaluated. The reinforcing benefits of TRGC can be confirmed from the load-deflection graph in terms of ultimate load-carrying capacity, post-peak behavior, and failure mode. An energy absorption capacity of 80.06% was found for TRGC-4 L beams compared to TRGC-1 L beam specimens (43.76%), i.e., TRGC specimens with 4 layers showed improved strength and ductility compared to one layer of carbon textile. The failure surface of the TRGC sample was examined using Scanning Electron Microscope (SEM), and fiber-matrix interaction was identified. Hence, despite the high cost of carbon yarn, TRGC can be used for special applications where corrosion protection and durability are controlling parameters.

POROUS POLYMER SCAFFOLDS DERIVED FROM BIORESOURCES FOR BIOMEDICAL APPLICATIONS

"The development of sustainable materials in medical treatment for the controlled release of drugs has generated interest in the field in view of the environmental and energy challenges faced during the continuous production of materials in the sector. In the present study, the potential use of sponges based on combinations of three types of starch (corn, wheat, and rice starch) with poly(vinyl alcohol) was investigated to evaluate their morphological properties, swelling ratio, in vitro biodegradation, antibacterial activity, hemolysis, and blood clotting index. The synthesis process is based on a cost-effective method for wide application in the medical industry, yielding sponges with a high swelling index of up to 8 times the original volume. A slight antibacterial activity was also observed when rice and corn starch were used. In addition, different morphological and physical properties were observed depending on the type of starch added to the formulation, allowing a variety of responses to treatment requirements, depending on factors such as the duration of treatment and the patient’s blood characteristics in terms of clot formation or immune response."

Evaluation of workability, microstructure and mechanical properties of recycled powder geopolymer reinforced by waste hydrophilic basalt fiber

The recycled powder geopolymer (RPG) is an environmental-friendly cementitious material prepared from recycled powder (RP) recovered from construction waste. The preparation of geopolymers has promoted the development of sustainable materials, but the great brittleness limits the application scenarios. In this paper, the waste hydrophilic basalt fiber (WHBF) was used to reinforce RPG and the mechanical properties, toughness and microstructure were evaluated. The results indicated that the addition of WHBF significantly improved the compressive, flexural and tensile strength of the RPG. Adding 0.6% WHBF with 6 mm in length and 13 μm in diameter improved the compressive strength, flexural strength and tensile strength by 59.43%, 85.20% and 121.74% in 28 days, respectively, compared to the control group. The single fiber pull-out test and Digital Image Correlation (DIC) analysis indicated that the interfacial properties of the WHBF with appropriate geometric parameters were high and the direction and rate of crack growth were significantly changed, which greatly improved the toughness of the matrix. The analysis of water absorption and Mercury Intrusion Porosimetry (MIP) showed that although the incorporation of WHBF increased the porosity of RPG, the pore size was small and had no adverse effect on the matrix. The microstructure analysis showed that the addition of WHBF benefited the formation of additional gel, which provided a better bonding and frictional stress transfer path for the composites. Meanwhile, the energy absorption capacity of the composites was significantly improved and the crack propagation was inhibited. Furthermore, the WHBF enhanced the long-term drying shrinkage performance of RPG. This work suggested that the recycled powder geopolymer reinforced by waste hydrophilic basalt fiber shows excellent potential for application.

Debugging periodate oxidation of cellulose: Why following the common protocol of quenching excess periodate with glycol is a bad idea

Periodate oxidation of cellulose to produce “dialdehyde cellulose” (DAC) has lately received increasing attention in sustainable materials development. Despite the longstanding research interest and numerous reported studies, there is still an enormous variation in the proposed preparation and work-up protocols. This apparently reduces comparability and causes reproducibility problems in DAC research. Two simple but prevalent work-up protocols, namely glycol quenching and filtration/washing, were critically examined and compared, resulting in this cautionary note. Various analytical techniques were applied to quantify residual iodine species and organic contaminations from quenching side reactions. The commonly practiced glycol addition cannot remove all oxidising iodine compounds. Both glycol and the formed formaldehyde are incorporated into DAC's polymeric structure. Quenching of excess periodate with glycol can thus clearly be discouraged. Instead, simple washing protocols are recommended which do not bear the risk of side reactions with organic contaminants. While simple washing was sufficient for mildly oxidised celluloses, higher oxidised samples were more likely to trap residual (per)iodate, as determined by thiosulfate titration. For work-up, simple washing with water is proposed while determining potential iodine contaminations after washing with a simple colorimetric test and, if needed, removal of residual periodate by washing with an aqueous sodium thiosulfate solution.

Recycling of titanium as reinforcement in cast aluminium alloy A356 for improving the microstructural refinement and mechanical performance towards a sustainable material development

A356 is one of the most commonly used Al-Si cast alloy containing copper, magnesium and titanium, as other predominant alloying elements. Due to its wide application in domains where dominant loading is compressive in nature, various research work is being carried out to improve the compressive performance of A356 alloy by adding particulate reinforcement in it, converting it to metal matrix composite. However, ceramic particles added as reinforcement have always been posing challenges due to the poor wettability and weak interface bonding. In the present research work, an attempt is made to recycle titanium in a greener way of adding it to Aluminium alloy as a strengthening reinforcement which shall address the interface boding issues due to better compatibility of Titanium and Aluminum – both being metals. 5% by weight of micro and nano-sized Titanium particles is added to A356 through stir casting method. Cast material was then subjected to hot extrusion. The as-cast and extruded composites are studied for the micro structural evolution and mechanical performance against the base alloy. Results indicate that the performance of the composite is found to be significantly enhanced as compared with the base alloy in terms of strength, hardness and ductility. Increased mechanical performance is attributed to refinement of dendrite size, presence of uniformly distributed Ti particle, and partial diffusion of Ti into the Al matrix.

Computational Design and Manufacturing of Sustainable Materials through First-Principles and Materiomics.

Engineered materials are ubiquitous throughout society and are critical to the development of modern technology, yet many current material systems are inexorably tied to widespread deterioration of ecological processes. Next-generation material systems can address goals of environmental sustainability by providing alternatives to fossil fuel-based materials and by reducing destructive extraction processes, energy costs, and accumulation of solid waste. However, development of sustainable materials faces several key challenges including investigation, processing, and architecting of new feedstocks that are often relatively mechanically weak, complex, and difficult to characterize or standardize. In this review paper, we outline a framework for examining sustainability in material systems and discuss how recent developments in modeling, machine learning, and other computational tools can aid the discovery of novel sustainable materials. We consider these through the lens of materiomics, an approach that considers material systems holistically by incorporating perspectives of all relevant scales, beginning with first-principles approaches and extending through the macroscale to consider sustainable material design from the bottom-up. We follow with an examination of how computational methods are currently applied to select examples of sustainable material development, with particular emphasis on bioinspired and biobased materials, and conclude with perspectives on opportunities and open challenges.

The Future of Green Building Research – A Cascade Approach of Bibliometric Analysis and Topic Modelling

Green building research has received a lot of attention from both academicians and practitioners. Even though, this has resulted in a surge in Green Building literature in the recent times, the review of the literature has either being too focused on specific aspects or too broad. This study attempts to address this issue by employing a combination of bibliometric analysis and topic modelling. The inclusion of a stringent quality filter and use of CorEx topic modelling has enabled us to generate a list of future research directions, which were further streamlined through manual intervention. The study has revealed a few very promising few research directions including the application of Artificial Intelligence (AI) in Green Building, Building Information System (BIM) for Green Building, development of sustainable materials and construction methods, socio-economic impact assessment of Green Buildings and incorporation of Internal Environmental Quality principles into built environment. The findings of the study are an integration of recommendations by many impactful studies in the Green Building literature and have tried to be a true testament to the idea that ‘the whole is greater than the sum of its parts’.

Preface

The International Conference on Innovative Technology for Smart Construction Materials and Sustainable Infrastructure (ITSCMSI-2022) was successfully held on October 14th and 15th 2022. The ITSCMSI-2022 was organized by Department of Civil Engineering, Velagapudi Ramakrishna Siddhartha Engineering College, Vijayawada, A.P, India. Innovative and sustainable development is one of the leading civilization ideas in the field of Civil Engineering that has gained importance among the researchers in the recent past. In keeping view that the primary objective of the International Conference on Innovative Technology for Smart Construction Materials and Sustainable Infrastructure (ITSCMSI-2022) to provide a platform to the researchers and practitioners from both academia as well as industry to meet and share cutting-edge development in the Civil Engineering in line with the conference theme “Building the World with Innovative Structures towards a Sustainable Future”. The scope of the conference is to gather scientists, practitioners, members of technical committees and users of technical recommendations, to jointly at the same place discuss and envision the future sustainable development of materials, systems and structures in a holistic, global way. Thus, it aims at providing a premier platform for researchers, practitioners and educators to present and discuss the most recent innovations, trends, and concerns as well as practical challenges encountered and solutions adopted in the fields of Civil Engineering.The conference focuses on latest research in different areas of civil engineering with special emphasis on sustainable construction practices. The main theme of the conference is “Building the World with Innovative Structures towards a Sustainable Future” and it is divided into seven sub-themes:1. Smart materials and sustainable construction,2. Sustainable infrastructure in Structural Engineering3. Sustainable infrastructure in Geotechnical and Transportation Engineering4. Sustainability in Environmental Engineering5. Sustainability in Irrigation, Water Resources and Management6. Sustainability in Construction Management, and7. Remote Sensing and GIS Applications in SustainabilityThe ITSCMSI-2022 received about 120 abstracts from various fields of Civil Engineering and out of which 93 full-length papers were received. The research manuscripts deal with Innovative Technologies and Sustainable Materials in Civil Engineering.Hundreds of attendees, paper presenters, researchers and students have been benefited in many ways from this conference. About 51 scientific papers were presented in the conference by the authors from various countries through online platform. Four eminent and well distinguished experts in the field of civil engineering were invited to deliver their keynote speeches and share their knowledge along with their rich experience in the applications of the advancements in sustainable materials and infrastructure in civil engineering to the participants.In summary, the success of the conference is a team effort. This conference could not be organized without the dedicated efforts from all our committee members and hence I am grateful to all the committee members who worked very hard to make this event a successful one. We would also like to thank all the authors who have submitted their papers to the conference and like to thank the editors and reviewers who have contributed to the thorough review process thereby ensuring quality publication of the conference proceedings. We hope that you will find this conference thought provoking and engrossing, and you had a valuable experience by sharing ideas with others at this conference.SincerelyDr. Hanuma KasaganiCo-ConvenerITSCMSI -2022Email: hanumakasagani@vrsiddhartha.ac.inList of Committes are available in this Pdf.

Study on The Application of Processed Municipal Solid Waste Ash for Sustainable Construction Materials

The total amount of solid trash produced in India is 160038.9 TPD, according to the Annual Report on Solid Waste Management (2020–21), CPCB, Delhi. Out of which, Tamil Nadu created 13422 TPD of solid waste, of which 9430.35 TPD was processed, and 2301.04 TPD was landfilled. The researchers have been forced to look at alternative processes and materials for the manufacturing of construction materials utilizing processed municipal solid waste ash (PMSWA) due to the increased demand for environmentally friendly and sustainable products. This research work focused on the replacement of fine aggregate by (0%, 10%, 30% and 50%) Processed Municipal Solid Waste Ash (PMSWA) in the Solid Blocks. This research enhances the sustainable material development in the construction industry. SEM study showed that specimens with CTR do not have any cracking on their fracture surfaces, unlike samples without CTR. This study examines the material’s physical characteristics, including its mechanical attributes like compressive strength and flexural strength as well as its chemical composition using XRF. It demonstrates that the substitution or addition of PMSWA to construction materials is appropriate, cost-effective, and safe.

Mechanoredox Catalysis Enables a Sustainable and Versatile Reversible Addition-Fragmentation Chain Transfer Polymerization Process.

The sustainable synthesis of macromolecules with control over sequence and molar mass remains a challenge in polymer chemistry. By coupling mechanochemistry and electron-transfer processes (i.e., mechanoredox catalysis), an energy-conscious controlled radical polymerization methodology is realized. This work explores an efficient mechanoredox reversible addition-fragmentation chain transfer (RAFT) polymerization process using mechanical stimuli by implementing piezoelectric barium titanate and a diaryliodonium initiator with minimal solvent usage. This mechanoredox RAFT process demonstrates exquisite control over poly(meth)acrylate dispersity and chain length while also showcasing an alternative to the solution-state synthesis of semifluorinated polymers that typically utilize exotic solvents and/or reagents. This chemistry will find utility in the sustainable development of materials across the energy, biomedical, and engineering communities.

Mechanoredox Catalysis Enables a Sustainable and Versatile Reversible Addition‐Fragmentation Chain Transfer Polymerization Process

AbstractThe sustainable synthesis of macromolecules with control over sequence and molar mass remains a challenge in polymer chemistry. By coupling mechanochemistry and electron‐transfer processes (i.e., mechanoredox catalysis), an energy‐conscious controlled radical polymerization methodology is realized. This work explores an efficient mechanoredox reversible addition‐fragmentation chain transfer (RAFT) polymerization process using mechanical stimuli by implementing piezoelectric barium titanate and a diaryliodonium initiator with minimal solvent usage. This mechanoredox RAFT process demonstrates exquisite control over poly(meth)acrylate dispersity and chain length while also showcasing an alternative to the solution‐state synthesis of semifluorinated polymers that typically utilize exotic solvents and/or reagents. This chemistry will find utility in the sustainable development of materials across the energy, biomedical, and engineering communities.

Combined Reprocessability and Self-Healing in Fluorinated Acrylic-Based Covalent Adaptable Networks (CANs)

Combining reprocessing and self-healing in one material provides an opportunity for the development of sustainable materials with enhanced mechanical properties. We developed fluorinated acrylic-based covalent adaptable networks (CANs) capable of self-healing and reprocessing by copolymerizing (2-acetoacetoxy)ethyl methacrylate (AAEMA), 2,2,2-trifluoroethyl methacrylate (TFEMA), and n-butyl acrylate (nBA), followed by cross-linking with tris(2-aminoethyl) amine (TREN). These materials exhibit the maximum stress at break of about 16 MPa and the storage modulus of ∼2.6 GPa in the −60 to 25 °C range. Capable of complete recovery of mechanical properties, these materials are reprocessable by compression molding at 120 °C. The recovery of physical and chemical properties involves the exchange reactions between vinylogous urethane linkages and primary amines. Upon multicycle reprocessing, junction densities and stored entropic energy are also recovered and preserved. These CANs self-heal under ambient conditions. Upon damage, initially C═O groups of vinylogous urethanes respond to perturbation by conformational changes, followed by the (E) → (Z) isomerization of C═C bonds accompanied by the conformational rearrangements of the CF3 and CH2 moieties. This reversible process leads to the recovery of dipolar interactions that facilitates self-healing under ambient conditions. The concept of equipping materials with dynamic cross-linking and self-healing attributes can be extended to other systems.

Plain metallic biomaterials: opportunities and challenges.

The 'plainification of materials' has been conceptualized to promote the sustainable development of materials. This perspective, for the first time in the field of biomaterials, proposes and defines 'plain metallic biomaterials (PMBs)' with demonstrated research and application case studies of pure titanium with high strength and toughness, and biodegradable, fine-grained and high-purity magnesium. Then, after discussing the features, benefits and opportunities of PMBs, the challenges are analyzed from both technical and regulatory aspects. Regulatory perspectives on PMB-based medical devices are also provided for the benefit of future research, development and commercialization.

Printed Humidity Sensors from Renewable and Biodegradable Materials

AbstractIncreasing environmental concerns raised by the accumulation of electronic waste draws attention to the development of sustainable materials for short‐lived electronics. In this framework, printed capacitive humidity sensors and temperature resistive detectors composed exclusively of biodegradable materials: shellac, carbon‐derived particles, and egg‐albumin are reported. The sensor platform comprises interdigitated electrodes serving as a capacitive transducer for humidity sensing, and a serpentine used as a resistive temperature detector. Both the interdigitated and serpentine electrodes are manufactured by screen‐printing carbon ink on a shellac substrate. The humidity sensors are constructed by drop‐coating egg albumin on the interdigitated carbon electrodes and the temperature detector is prepared by encapsulating the serpentine design with shellac. Shellac is shown to be a biodegradable alternative to hydrophilic cellulose‐derived substrates, with the capacitive humidity sensors demonstrating a sensitivity of 0.011% RH−1. The response and recovery times on shellac are 12 and 20 times faster than on cellulose‐based substrate, and the serpentine resistive temperature detectors have a temperature coefficient of 5300 ppm K−1. At the end of their service‐life, the sensors produced are home compostable and can be environmentally friendly disposed, potentially enabling their future use for sustainable and environmentally friendly smart‐packaging, agricultural sensing, or point‐of‐care testing.

Critical Barriers to Successful Implementation of Mn-Rich Cathodes: A Study of Low SOC Impedance

The development of sustainable materials for lithium-ion batteries is of paramount significance with the ever-growing demand of energy storage for the transportation sector. Lithium- and manganese-rich oxides are of great interests because of inherently high capacities/energies and the potential economic benefits associated with earth-abundant manganese-based compositions. With several challenges hindering the commercialization of these cathodes, there have been many studies on understanding the mechanisms of voltage fade, hysteresis, and oxygen activity. However, relatively little attention has been given to understanding the impedance of these materials. In particular, the drastic rise in area specific impedance at lower states of charge, and the overall impedance rise on extended cycling due to surface issues, are critical barriers that need to be understood and addressed to accelerate deeper market penetration.This poster will present a detailed study of the impedance behavior in cobalt-free, lithium- and manganese-rich cathodes. A combined surface-treatment/electrolyte-additive has been used to probe the behavior over long-term cycling in the absence of (i.) surface issues, (ii.) the impedance rise due to electrolyte interactions, and (iii.) capacity loss. The results presented in the poster support the hypothesis that the anomalous rise in impedance at lower states of charge is directly associated with the bulk processes of voltage fade and voltage hysteresis. Furthermore, a preliminary conceptual model is presented for understanding the impedance behavior of these activated materials, which can be described as layered-type, ordered-domain network with facile Li diffusion, where interspersed, disordered, low-voltage sites within this network hinder the Li insertion.