Next Sustainability最新文献

In the last few years, hydrogen has attracted much attention because of its importance in the transition to a sustainable energy system and its use as a raw material in many industrial processes. In this context, chemical looping is proposed as an alternative to traditional methane reforming processes, where methane is partially oxidized by the lattice oxygen of a solid oxygen carrier instead of using water or pure oxygen. This work presents a thermodynamic analysis of MnWO₄ as an oxygen carrier and the compositions at equilibrium were calculated by minimizing the total Gibbs free energy of the system. To evaluate its possible integration into a chemical looping scheme, this study assesses the optimal reaction temperature and reactant molar ratio to attain high hydrogen yield while avoiding carbon formation. The findings suggest that temperatures exceeding 775°C and ratios above stoichiometry are necessary. For successful regeneration, air or water can be used. In the former case a stoichiometric ratio of 1.5:1 of O₂ to MnO/W is required, while for the latter, an excess of water in necessary.

Hydrocarbon proton exchange membranes (PEMs) which exhibit low-cost, improved robustness, and simple synthesis relative to perfluorosulfonic acid (PFSA) membranes, are of great significance for proton exchange membrane fuel cells (PEMFCs). Herein, we report a facile and affordable preparation of sulfonated and phosphonated poly (p-terphenyl perfluorophenyl)s PEMs via superacid-catalyzed Friedel−Crafts condensation of p-terphenyl and pentafluorobenzaldehyde monomers, following by highly selective para-substitution of fluorobenzene to graft ion exchange groups. The rigid and well-defined polymer structure with precisely controlled anionic groups, enables good phase separation and efficient ionic clustering to promote proton transport. Sulfonated and phosphonated PEMs show modest proton conductivities of 150 and 120 mS cm⁻¹ at 90 °C, and achieve H₂/air PEMFC peak power densities of 360 and 237 mW cm⁻² at 80 ℃, respectively. Interestingly, we find that phosphonated PEMs have significantly higher resistance to free radicals than sulfonated PEMs. Overall, the results suggest that our prepared hydrocarbon PEMs have potential applications for fuel cells.

Protonic ceramic fuel cells (PCFCs) have recently garnered significant interest due to their high efficiency and low emissions operating in the intermediate temperature range (400−700 °C). However, due to the lack of efficient key cell materials, especially cathode materials with triple-conducting (O²⁻/H⁺/e⁻) characteristics, the practical application of PCFCs lags behind other energy conversion technologies. Over the past decade, considerable efforts have been devoted to the development of efficient triple-conducting cathode materials, leading to a remarkable progress in PCFCs performance. This review provides a comprehensive summary of the development of cathode materials in PCFCs, including the reaction mechanism, essential cathode material features, regulation strategies, and recent advancements. Challenges and research perspectives in this field are also presented. The focus is on harnessing the fundamental principles of compositional engineering and advanced technologies to provide valuable guidance for the design and development of novel cathode materials for high-performance PCFCs and related fields.

Durability property is a critical performance indicator of concrete in different environments and locations. However, durability also plays a key role in the sustainability and climate resiliency of concrete structures which is mostly ignored in the context of ways to improve the sustainability of concrete materials and structures. Hence, this paper aims to bring focus to this area by presenting an overview of the critical role of concrete properties especially durability on the sustainability and climate resiliency of concrete structures. This paper first presents a general overview of concrete materials followed by the connection of concrete to sustainability and climate resiliency. Discussions from this paper indicate that to improve concrete sustainability, there is a need to use materials with lower environmental impacts upfront in addition to producing concrete with improved durability to ensure long-term performance. In other words, merely reducing the upfront embodied carbon of materials is not sufficient to achieve sustainable concrete if the impact of such alternative low-carbon materials used to replace the traditional materials in concrete is not considered. On the other hand, the climate resiliency of concrete structures is mostly dependent on improved durability which would sustain their adaptation over time to the impacts of the changing climate conditions. Overall, to achieve sustainability and climate resilience of concrete structures; lower environmental impact, higher durability performance and resilience to applicable climatic conditions must be achieved.

Miriti, derived from the leaves of the Amazon palm tree Mauritia flexuosa, is a foam-like material that can serve as a natural substitute for synthetic foams, offering the advantage of natural internal fiber reinforcement. This study assessed miriti’s mechanical properties and potential applications. With an average specific mass of 63 kg.m^–3, miriti is amongst the lightest natural solid materials. Its internal fiber reinforcement provides mechanical properties seven to 30 times higher than synthetic foams of similar density in the parallel-to-grain direction. Miriti is a green material and shows high potential for use in sandwich panel cores, thermal/acoustic applications requiring higher strength and stiffness, and load-bearing walls of small structures. Sustainable management of M. flexuosa by local communities is feasible, promoting their sustainable development. Additionally, miriti can inspire the design of synthetic foams reinforced with internal fibers.

Cocopeat has various distinguishing properties that encourage the slow decomposition and spontaneous Trichoderma growth. The cocopeat synthesizes responsive chemicals and regulatory mechanisms which assist in the Trichoderma growth. The exact chemical stimulant and efficient mechanisms governing the spontaneous Trichoderma growth in cocopeat remain unknown. The high lignin and cellulose concentration produces actinomycetes and deuteromycetes, which trigger slow decomposition in cocopeat. The chemical components, temperature, pH, nutrients, and aeration all have a direct impact Trichoderma growth and slow decomposition. The chemical constituents lignin, suberin, cutin, pectin, cellulose, and hemicellulose are analyzed with sodium hydroxide solution and examined using scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDAX), fourier transform infrared (FTIR) spectra, x-ray diffraction (XRD), and thermogravimetry. The decomposition dynamics are determined using a mettler thermogravimetric analyzer. Simultaneously thermogravimetry and differential scanning calorimetry are used to examine the stages of decomposition. The decomposition reactions are investigated using the distributed active energy model (DAEM). The glucose Murashige and Skoog (MS) media, chitin Murashige and Skoog (MS) media, Murashige and Skoog (MS) basal media, high-density oligonucleotide microarray, expressed sequence tag-based transcript and Blast2GO suite, hierarchical clustering and heat representation are involved in examination of Trichoderma species. The Upside regulating genes respond to signal transduction, transcription, translation, post-translational modification, and protein folding with the signal transcription factor Pac1 (PacC) for Trichoderma species growth. The dye decolorization assay, genome-wide gene family evolutionary analysis, and whole-genome sequencing were used to discover prospective genes for detecting high or slow decomposition in fungi. The methodologies and technology have the potential to investigate Trichoderma type, response chemicals, and mechanisms underlying Trichoderma growth and slow decomposition in cocopeat.

Compatible and environmentally clean activated carbon material was prepared via physicochemical method and used for harmful pollutant removal from aqueous solution. The performance of the pristine cottonseed cakes and its activated carbon was examined towards copper ions removal as targeted pollutant through adsorption process. The physicochemical properties of adsorbents were evaluated by numerous experimental techniques such as Fourier transform infra-red spectroscopy, Raman spectroscopy, scanning electron microscopy, the point of zero charge, iodine number and specific surface area. The effect of several key operational parameters such as contact time, adsorbent dose, pH, concentration and temperature were considered. Results of the adsorption tests exhibited significant sensitivity towards copper ions elimination at optimum conditions; the copper uptake capacity was enhanced with time up to equilibrium of 30 min with a minimum adsorbent dose of 0.1 g at alkaline pH of 10 for maximum concentration of 50 mg/L at room temperature (25 °C) and achieved appropriate adsorbed quantities of 51.56 mg/g for cottonseed cakes activated carbon (CCAC) and 48.5 mg/g for cottonseed cakes biosorbent (CCB). The values of point of zero charge are 2.63 and 6.32 for CCB and CCAC respectively which present high electrostatic attraction between positive charge of copper ions and negative charge of the surface at basic medium. Iodine number of 30.35 and 41.92 mg/g indicates random distribution of micropores. The specific surface area of CCAC (30.35 m²/g) is higher than the one of CCB (11.94 m²/g). FTIR shows good surface chemistry with various functional groups while Raman spectroscopy and SEM analyses revealed myriad morphological features and carbon phases (graphite and diamond). The adsorption of copper ions was described by pseudo second order kinetic model and favoured by Redlich Peterson isotherm corresponding to physisorption on CCB while the one CCAC involves chemical bonding and can be qualified as chemisorption mechanism as confirm by ΔH° of both materials.

The widespread use of Li-ion batteries (LIBs) in energy storage devices has resulted in the generation of additional waste which contains valuable metal ions and these metal ions are well known for their catalytic activities. The recovered black mass of cathode material was exposed to pretreatment with final calcination for 2 h at 800 ⁰C. After the calcination, the material was subjected to structural characterization (XRD, FE-SEM, EDAX, and XPS). In the present work, we have used spent LIBs cathode material as a catalyst for the oxidation reaction of benzyl alcohol to benzoic acid. The catalytic activity of this recovered cathode material was found to be highly efficient showing 100% conversion of benzyl alcohol with >99% selectivity of benzoic acid with lower catalyst loading of even 2%.

In this study, zinc oxide (ZnO) and zinc oxide-zirconium dioxide nanocomposites (ZnO@ZrO₂) were synthesized by a low-cost solution combustion route to study their structural, morphological, optical, and photocatalytic performance. The properties of synthesized nanocomposites were characterized by x-ray diffraction (XRD), UV–vis absorption spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Phase formation and purity were confirmed using XRD and EDS. Optical absorption spectra revealed that the addition of ZrO₂ significantly affected optical absorption and band gap energy. The band gap energy increased from 3.01 to 3.24 eV with addition of ZrO₂ in ZnO. FTIR spectra confirmed the formation of ZnO and ZnO@ZrO₂. SEM micrographs showed a significant change in the morphology of the ZrO₂ addition in ZnO. BET analysis showed surface area for sample P3 ([email protected]₂) was 28.9 m²/g while for sample P1 (ZnO) was 22.5 m²/g. In addition, the photocatalytic performance of ZnO and ZnO@ZrO₂ for the decomposition of methylene blue (MB) dye was studied for all samples exposed to solar light. The effect of different contents of ZrO₂ in ZnO@ZrO₂ in terms of degradation efficiency and degradation time are described in detail. The sample P3 showed highest photodegradation efficiency of 84.52 % at degradation time of 240 minutes.

There is a growing concern regarding the lack of sufficient justification for claims of "greenness" in research studies. This concern has sparked heated debates and prompted calls for mandatory discussions on adherence to green chemistry principles in studies that assert environmental friendliness. In response to this pressing issue, the present study introduces the ‘12 Principles of Red Chemistry’. These principles outline methodologies that prioritize immediate but risky chemical objectives over broader ecological considerations. Through the presentation of case studies, this discussion vividly illustrates the non-sustainability inherent in red chemistry practices. While green chemistry advocates for sustainable and environmentally responsible practices, red chemistry prioritizes short-term gains without adequate consideration for long-term environmental impacts. This contrast highlights the significance of green chemistry principles in guiding the chemical industry towards a more sustainable future. The comprehensive discussion on the Principles of Red chemistry serves as a guiding framework for understanding and evaluating the red chemical processes, emphasizing their potential risks and ecological impacts.