Electrochemical Properties Research Articles

Poly(Acrylic Acid)-Based Polymer Binders for High-Performance Lithium-Ion Batteries: From Structure to Properties.

Poly(acrylic acid) (PAA) and its derivatives have emerged as promising candidates for enhancing the electrochemical performance of lithium-ion batteries (LIBs) as binder materials. Recent research has focused on evaluating their ability to improve adhesion with silicon (Si) particles and facilitate ion transport while maintaining electrode integrity. Various strategies, including mixing modifications and copolymerization methods, are highlighted and the structural and physicochemical properties of these binders are examined. Additionally, the interaction mechanisms between PAA-based binders and active materials and their impact on key electrochemical properties such as initial Coulombic efficiency (ICE) and cycle stability are discussed. The findings underscore the efficacy of tailored PAA-based binders in enhancing the electrochemical properties of LIBs, offering insights into the design principles and practical implications for advanced battery materials. These advancements hold promise for developing high-performance lithium batteries capable of meeting future energy storage demands.

Sodium Vanadates for Metal-Ion Batteries: Recent Advances and Perspectives.

Rechargeable metal-ion batteries (MIBs) play a pivotal role in advancing the stable supply of renewable energy by efficiently storing and discharging electrical energy. In recent years, to propel the continuous advancement of MIB technology, numerous studies have concentrated on exploring and innovating electrode materials, aiming to engineer commercial batteries with high energy density, superior power density, and extended cycle life. Notably, sodium vanadates have garnered significant attention in the realm of MIBs owing to their distinctive crystal structures, abundant resource reservoirs, and exceptional electrochemical properties. This paper provides a prompt and comprehensive review of the research landscape for various sodium vanadates (such as NaxV2O5, Na1+ xV3O8, Na2V6O16·xH2O, etc.) in the domain of MIBs over the past five years. It delves into the structural characteristics, electrochemical performances, and energy storage mechanisms of these materials, while also proposing some effective strategies to augment their electrochemical capabilities. Building upon these insights and prevailing research outcomes, this review envisions the future developmental pathways of sodium vanadates for MIBs and aims to reveal the vast potential of sodium vanadates in the emerging energy storage field and provide researchers with clear insights and perspectives for developing optimal sodium vanadate electrodes.

Chitosan/Nitrogen-doped graphene nanocomposite for supercapacitor application

Abstract In this study, we explore the chitosan/nitrogen-doped graphene oxide (CS-NGO) nanocomposite using the hydrothermal method and incorporate it onto carbon paper by a deep coating technique for supercapacitor applications. The incorporation of CS-NGO, a non-toxic and environmentally friendly material, significantly enhances the electrochemical performance. The electrochemical properties are explored by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and impedance spectrum (EIS). The analyses reveal a specific capacitance increase from 2.84 μF cm−2 to 3.96 μF cm−2, a reduction in charge transfer resistance (Rct) from 24.75 Ω to 16.74 Ω, a decrease in Rs resistance from 4.9 Ω to 0 Ω, and a reduction of equivalent series resistance (ESR) from 12.87 Ω to 6.41 Ω. In addition, the results demonstrate remarkable enhancements in energy density and power density and an excellent cyclic stability of 100% over up to 1000 CV cycles of the CS-NGO electrode. These improvements are due to the potential of CS-NGO nanocomposite in developing high-performance, sustainable supercapacitors with the growing demand for green and safe energy storage solutions. This sign of success in this research is due to the new nanocomposite.

Synthesis of Porous Carbons from Candlenut Shells Using Various Types of Activators for Environmentally Friendly Supercapacitors

Porous carbon is one of the promising electrode materials for supercapacitors due to its unique and engineerable microstructural properties. The study of the synthesis of porous carbon from waste biomass is very important due to the abundance of natural resources, low cost production and contribute to solving environmental problems. In this study, porous carbons derived from candlnut shell with various type of activator was studied the chemical structural, morphological and electrochemical properties then evaluated as electrodes for supercapacitor. We have been successfully synthesized of porous carbon from candlenut shells using three steps of the process, i.e.: carboni-zation, activation and calcination. Carbonization was carried out at 700°C in a furnace using a closed crucible to minimize the oxygen. The chemical activation conducted using three types of activators, i.e. ZnCl2, H3PO4 and KOH then calcination process by heated at 800°C for 1 h under Ar flow. The results of the Fourier-transform infrared (FTIR) analysis show that the carbonization process increases the content of aromatic C=C functional groups and reduce the OH, C-H, C-O and C=O functional groups. The carbonization process has also increased the electrical conductivity of the sample around 0.8525 S/m. The results of Scanning Electron Microscope (SEM) images can be observed that the activation process of carbon has formed which was indicated by the appearance of many pores on the surface area of carbon. N2 adsorption/desorption isotherms (Brunauer–Emmett–Teller (BET)) characterization was indicated that the porous carbon is dominated by mesoporous with a pore size around 2-50 nm. BET characterization also can be determined the surface area of porous carbon around 477 m2/g for ZnCl2, 636 m2/g for H3PO4, and 681 m2/g for KOH. This synthesized materials are further employed in a symmetric supercapacitor using simple glass cell. The best performance of supercapacitor achieved by KOH porous carbons with 16.30 F/g of specific capacitance, 2.26 Wh/kg of energy density and 1038 W/kg of power density.

Zinc cobalt sulfide with carbon (graphene oxide and CNT) based nanocomposite as positive electrode for asymmetric coin cell supercapacitors

Abstract The world dependence on portable electronic devices has increased the demand for high-performance energy storage devices. The use of transition metal sulfides as faradaic electrode materials for electrochemical energy storage is rapidly increasing due to their high energy density. Herein Zinc Cobalt Sulfide (ZCS) with graphene oxide (GO) and carbon nanotubes (CNT) were used to create an interconnected ZCS composite network using a solvothermal technique. The materials were characterized by utilizing XRD, FT-Raman, TGA, FESEM/EDX, XPS, and BET. The electrochemical performance of the materials was examined using cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). The prepared electrodes exhibited both pseudocapacitor behavior and double-layer capacitor behavior, indicating the hybrid nature. Furthermore, All the electrode ZCS, ZCS/GO, ZCS/CNT, and ZCS/GO/CNT electrodes demonstrated higher capacitance behavior, with values of 420, 551, 585 and 811 F g−1 at 1 A/g. Among these ZCS/GO/CNT electrode exhibits outstanding electrochemical properties, with a notable retention of 81.08% at 10 Ag−1 because Combining ZCS nanoparticles with interconnected GO and CNT provides excellent electronic conductivity and stability. The assembled ZCS/GO/CNT//graphene oxide asymmetric coin cell (ACC) supercapacitor showed a high energy density of 33.3 Wh kg–1 at a power density of 624 W kg–1. The 3D nanostructure of ZCS/GO/CNT/Graphene oxide has great potential for developing foldable energy storage devices.

Probing structural and electrochemical properties of a 2D CoMoO4@hBN nanocomposite as pseudocapacitive electrode for high-performance supercapacitors

The effectiveness of energy storage is largely determined by the electrode material's performance in critical areas. Enhancements in ion transport, cyclic stability, rate capability, and specific capacitance directly boost the supercapacitors' overall performance and broaden their application potential. This study aims to enhance these properties by incorporating hexagonal boron nitride (hBN) into cobalt molybdate (CoMoO4) material in a 1:1 stoichiometric ratio. The CoMoO₄@hBN nanocomposite was synthesized using a hydrothermal method followed by ball milling. The X-ray diffraction (XRD) analysis confirmed the formation of a single-phase CoMoO4@hBN composite, with a significant increase in crystallite size from 18.21 nm in pure CoMoO₄ to 25.6 nm, along with a slight shift in diffraction peaks, indicating enhanced crystallinity and structural defects due to the substitution of oxygen with boron atoms. Raman spectroscopy revealed that the composite retains the characteristic peaks of both CoMoO₄ and hBN, with stable sharp peaks at 936 cm−1 (Mo=O bond) and 1367 cm−1 (E2g peak of hBN) even after 20 depth measurements, confirming successful conjugation and consistent vibrational properties. The X-ray photoelectron spectroscopy (XPS) showed a slight shift in Co 2p and Mo 3d binding energies to higher values, suggesting improved electronic interactions between CoMoO4 and hBN, which could enhance the composite's conductivity. The electrochemical analysis demonstrated that incorporating h-BN significantly boosts the electrode's performance compared to pristine CoMoO4, with about 37 % increase in specific capacitance at 1 A g−1, reduced charge transfer resistance (0.11 Ω), and superior cyclic stability with 96 % capacitance retention after 5000 cycles. These findings indicate that hBN enhances both the electrical conductivity and structural integrity of CoMoO4, positioning the CoMoO4@hBN composite as a promising material for high-performance supercapacitors.

Supercapacitor performance of pure and Ni-doped CuO electrodes prepared by USP

Abstract In this study, the ultrasonic spray pyrolysis (USP) technique was employed to fabricate pure and 3% Ni-doped copper oxide (CuO) thin films (TFs) on In2O3/SnO2 (ITO) coated glass substrates. X-ray diffraction (XRD) analysis revealed that both pure and 3% Ni-doped CuO TFs exhibit a polycrystalline structure with the tenorite phase oriented preferentially along the (111) plane. The morphological properties of these TFs were characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM) imaging. Energy dispersive x-ray spectroscopy (EDX) confirmed that the deposited TFs achieved the desired stoichiometry. The electrochemical properties of both pure and 3% Ni-doped CuO TFs were evaluated using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS). At a current density of 1 A g−1, the specific capacitance of pure CuO TFs was found to be 78 F g−1, decreasing to 2 F g−1 at 10 A g−1. In contrast, Ni-doped CuO TFs exhibited a specific capacitance of 722 F g−1 at 1 A g−1 and 20 F g−1 at 10 A g−1. These results indicate that Ni-doping significantly enhances the specific capacitance values. The superior performance of Ni-doped CuO electrodes is attributed to their uniformly high porosity and improved electrical conductivity, demonstrating Ni-doped CuO as an optimal electrode material for pseudocapacitors.

LiTFSI salt concentration effect for well‐balanced ion transport and physical properties in nanocellulose‐reinforced PEO#600 solid electrolytes

AbstractPoly(ethylene oxide) (PEO) with an oxygen group serves as a reactive site for the pathway of lithium‐ion transport. Reducing the PEO crystal domain in solid electrolytes is an extremely efficient approach for enhancing the mobility of ions. The present study applied various EO/Li molar ratios to modify the physical and electrochemical properties of PEO nanocomposite reinforced by nanocellulose. An elevated lithium salt concentration causes a gradual decline in crystallinity and mechanical strength. The electrochemical performance of the 13 EO/Li molar ratio voltammogram and charge–discharge shows efficient Li‐ion transport with 5.6 × 10−4 S/cm conductivity at room temperature and 131 mA h g−1 initial discharge capacity. The shifting glass transition and melting point at lower temperatures (−40.5 to −44.5°C and 45.3–43.8°C) suggest greater ion mobility throughout the large non‐crystalline structure. Lithium ions are limited by membrane weakening and re‐crystallization caused by high lithium salt (EM_11) concentrations. EM_13 has the highest specific capacity, operating voltage, and lithium transfer number depends on balanced electrochemical performance and physical features. XPS surface chemistry analysis explains LiF, Li2CO3, and Li2O solid electrolyte interfaces (SEI) in EM samples. A lower Li2O (11.62 at.%) than LiF (38.4 at.%) after cycling enhances Li‐ion diffusion and cell reversibility.

Hydrothermal synthesis of rGO and MnCoS composite for enhanced supercapacitor application

Nanostructured materials incorporating transition metal sulfides have demonstrated considerable potential across various applications, particularly in the realms of energy production and storage. Sulfide-based material preparation is a challenging and costly procedure that requires a high temperature and reducing atmosphere. This work reports that manganese cobalt sulfide (MCS) and reduced graphene oxide composite manganese cobalt sulfide (rMCS) were successfully prepared through a hydrothermal method. Various characterization techniques were employed to analyze the prepared materials, including X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller analysis, and X-ray photoelectron spectroscopy. In a three-electrode system, MCS and rMCS electrodes exhibit an excellent specific capacitance of 1695 and 1925 F g−1 at 1 A g−1 current density respectively. MCS delivers the capacitance retention of 99% and rMCS exhibits the capacitance retention of 100% capacitance retention over 5000 consecutive cycles. The constructed asymmetric supercapacitor electrode (rMCS//rGO) exhibits the energy and power density of 64 Wh kg−1 at 799 W kg−1, respectively with outstanding cyclic stability of 97.4% even after 10,000 cycles. The exceptional electrochemical properties of MCS with rGO composite electrode indicate that they would make an outstanding electrode material for cutting-edge energy storage devices.

On the Electrochemical Properties of Poly(Vinylidene Fluoride)/Polythiophene Blends Doped with Lithium‐Based Salt

AbstractIn this study, polymer blends of polythiophene (PTH) and poly(vinylidene fluoride) (PVDF) are investigated by focusing on their structural and electrochemical characteristics. These blends displayed immiscibility confirmed through field emission scanning electron microscopy (FE‐SEM) and interaction assessments. PTH's role as a plasticizer is evident, diminishing crystallinity. A rise in PTH level led to a lower glass transition temperature and a higher melting point, suggesting reduced intermolecular forces and increased polymer chain flexibility. Conversely, a dispersed phase presence elevated the melting point, restricting chain movement and crystallization. The thermal properties of blends are enhanced by increased PTH content. Applying the Vogel–Tammann–Fulcher model to ionic conductivity measurements, it observed a direct relationship between temperature and free volume, impacting conductivity and ion transport numbers. Certain materials exhibit increased activation energies, indicating substantial thermodynamic barriers to local motion. Higher PTH content within the PVDF matrix notably increased the lithium ion transfer number from 0.22 to 0.71, a change tied to the C–S–C structure of polythiophene. However, elevated PTH levels also led to diminished negative charge transfer and ionic conductivity in the PTH‐PVDF blend compared to pure PVDF, likely due to an ionic conduction hindrance.

Ce-Doped Iron Oxide Anticorrosive Coatings: Effect of c(Ce4+):c(Fe3+) Ratio on Structure, Morphology, and Coating Anticorrosion Performance

Utilizing hydrothermal methods, Ce-doped iron oxide nanoparticles were synthesized from precursor solutions under different c(Ce4:c(Fe3+) precursor solutions. The effects of the c(Ce4+):c(Fe3+) ratio in the precursor solutions on the nanoparticle morphology and nanoparticle structure of the Ce-doped iron oxide were investigated using X-Ray diffraction, transmission electron microscopy, and scanning electron microscopy. Fourier transform infrared spectroscopy (FTIR) was used to examine the bond energy strength of the Ce-doped iron oxide nanoparticles. The electrochemical properties of the Ce-doped iron oxide nanoparticles were tested using an electrochemical workstation and a saltwater immersion resistance test. The corrosion resistance of Ce-doped iron oxide coatings at different c(Ce4+):c(Fe3+) ratios was systematically analyzed, uncovering corrosion resistance mechanisms and self-healing capabilities. The results show that as the c(Ce4+):c(Fe3+) ratio decreases, the lattice constants of the samples increase along with the average grain size. Both smaller and larger c(Ce4+):c(Fe3+) ratios are detrimental to lattice distortion in α-Fe2O3. The reduced number of valence electrons provided by cerium ions in Ce-doped iron oxide hinders the generation of holes and exerts a minor influence on the crystal band structure, leading to weaker electrochemical stability. The Ce-doped iron oxide coating prepared at a c(Ce4+):c(Fe3+) ratio of 1:60 readily generates a higher number of reactive hydroxyl radicals during corrosion, thus exhibiting enhanced self-healing capabilities and corrosion resistance.

Electrochemical Impedance Spectroscopy Study of Ceria- and Zirconia-Based Solid Electrolytes for Application Purposes in Fuel Cells and Gas Sensors

In this study, the structural and electrochemical properties of commercial powders of the nominal compositions Ce0.8Gd0.2O1.9, Sc0.1Ce0.01Zr0.89O1.95, and Sc0.09Yb0.01Zr0.9O1.95 were investigated. The materials are prospective candidates to be used in electrochemical devices, i.e., gas sensors and fuel cells. Based on a comparison of the EIS spectra in different atmospheres (synthetic air, 3000 ppm NH3 in argon, 10% H2 in argon), the reactions on the three-phase boundaries were proposed, as well as the conduction mechanisms of the electrolytes were described. The Ce0.8Gd0.2O1.9 material is a mixed ionic–electronic conductor, which makes it suitable for anode material in fuel cells. Moreover, it exhibits an apparent and reversible response for ammonia, indicating the possibility of usage as an NH3 gas-sensing element. In zirconia-based materials, electrical conduction is realized by oxygen ion carriers. Among them, the most promising from an applicative point of view seems to be Sc0.09Yb0.01Zr0.9O1.95, showing a high, reversible reaction with hydrogen.

Methacrylate-Containing <i>n</i>-Derivatives of <i>N</i>,<i>N</i>-Diethyl-4-(Phenyldiazenyl)Aniline as Initiators in Two-Photon Polymerization

The possibility of using a number of methacrylate-containing N,N-diethyl-4-(phenyldiazenyl)anilines with various para-substituents with respect to the azo group (-H, -Br, -NO2) as photoinitiators of radical polymerization is considered. The electrochemical and photoluminescent properties of these compounds have been studied. In the presence of azo dyes, two-photon photopolymerization of pentaerythritol triacrylate was carried out by focused radiation from a femtosecond laser with a wavelength of 780 nm. Structures with minimum linear element sizes of 94 ± 5 nm were obtained by DLW nanolithography, as well as 3D microstructures of complex architecture.

Eco-Friendly High Microporosity Low Temperature Plasma Exposed Activated Carbon from Coconut Shell For nano Hybrid Super Capacitors

Abstract This study looked at the structural, chemical, and electrochemical properties of coconut shell activated carbon (CSAC) before and after plasma treatment. Structural analysis using X-ray diffraction (XRD) demonstrated that plasma treatment improves graphitic structure by plans at (002) and (101) for higher angles. Chemical investigation utilizing Fourier-transform infrared spectroscopy (FTIR) revealed an increase in hydroxyl groups and carboxylic content following plasma treatment, which enhances electrochemical performance. Raman spectroscopy revealed a drop in the ID/IG ratio from 1.00 to 0.90, indicating enhanced graphitic order. Scanning electron microscopy (FESEM) showed that plasma treatment improves surface shape, while elemental analysis assessed the high carbon content (76.56% by weight). Contact angle measurements showed a decrease from 114° to 65°, showing improved hydrophilicity after treatment. Electrochemical investigation shows that the plasma-treated CSAC had a maximum specific capacitance of 1612 F/g, compared to 729 F/g for the untreated CSAC, and a total capacitance of plasma treated1685 F/g are untreated 1400 F/g. The cyclic stability tests indicated that the plasma-treated CSAC retained 94% capacitance and 98% coulombic efficiency after 3000 cycles, which is superior to the untreated CSAC's 92% capacitance retention and 95% coulombic efficiency. This reveals that plasma-treated CSAC has significantly improved performance and stability, making it an excellent alternative for high-performance and cost-effective energy storage applications.

Non‐Electron Withdrawing Unit Copolymerization to Enhance Photo‐Stability of Thiophene‐Based Organic Solar Cells

The impact of non‐electron withdrawing unit copolymerization on photostability of fullerene‐based organic solar cells is investigated using two donor polymers namely: benzodithiophene‐4,8‐dione (BDD) unit copolymerized with α‐quaterthiophene (4 T) unit (PBDD4T) and poly‐3‐hexyl‐thiophene (P3HT). The optical and electrochemical properties of the polymers reveal a deeper highest occupied molecular orbital (HOMO) and broader absorption in PBDD4T in comparison to P3HT owing to the BDD copolymerization. The copolymer achieves a higher power conversion efficiency (PCE) compared to the P3HT‐based device due to its higher VOC and Jsc that resulted from its deeper HOMO level and broader absorption. The photostability study reveals that PBDD4T‐based devices lost 14% of its initial PCE relative to the 48% reduction in PCE for P3HT‐based devices after 7 h of irradiation. Further investigation into the reasons behind the difference in the photostability suggests that photooxidation and recombination induced by irradiation in PBDD4T‐based devcie are suppressed by BDD‐copolymerization, maintaining better stability. In contrast, P3HT:PC71BM‐based solar absorber shows bimolecular recombination due to photoaging processes, which have negatively impacted the device stability. The reduction in stability of both devices is evident by lower photogenerated current attributed to reduced charge mobility and increased surface roughness.

Reevaluation of XPS Pt 4f peak fitting: Ti 3s plasmon peak interference and Pt metallic peak asymmetry in Pt@TiO2 system

The structural, electronic, and electrochemical properties of noble metals supported on transition metal oxides, such as Pt nanoparticles (NPs) supported on TiO2 (Pt@TiO2), have been extensively studied for their relevance to energy technologies, including photocatalysis, electrocatalysis, and electrochemical energy conversion. As the need to lower the amount of Pt and other noble metals used in energy conversion systems becomes urgent, it is essential to accurately quantify the loading of these metals and electronic density redistribution between them and their supports. X-ray photoelectron spectroscopy (XPS) is widely used for the identification and quantification of chemical species. In particular, fitting of the Pt 4f spectra for Pt@TiO2 is frequently performed to determine the chemical environment and oxidation state of Pt, which strongly affect the physical behavior and catalytic performance of this system. Here, we show that neglecting contributions due to the Pt surroundings and the asymmetry of the Pt metal peak in the line shape fitting can lead to severe mischaracterization of the oxidation state of Pt. We quantify the effects of background contributions that stem from the TiO2 support and discuss how factoring in the strong asymmetry of Pt 4f doublets, which stems from the shake-up type processes, affects the interpretation of Pt 4f XPS line shape.

A, the synthesis and evaluation of Polyvinyl Alcohol/Silver Nanoparticles (PVA/AgNPs) via electrochemical method: a model test for antioxidant and antibacterial activities

Background: Silver nanoparticles that are artificially created have electrochemical properties that work as antibacterial agents and are widely used in several areas ofresearch. Purpose: This work aimed to generate silver nanoparticles by the electrochemical method, using PVA as a stabilizer, and assess their antioxidant and antibacterial characteristics. Experimental procedures: Silver nanoparticles were synthesized using an electrochemical method, utilizing a stabilized polyvinyl alcohol solution at a concentration of 1 g/L. The validation of the PVA/AgNPs synthesis was performed using a UV-Vis spectrophotometer. The AgNPs were characterized by FT-IR, DLS, Zeta potential, and AFM. The antioxidant capabilities of PVA/AgNPs were assessed utilizing DPPH methods. The antibacterial activity of PVA/AgNPs against Salmonella enterica, Escherichia coli, Staphylococcus aureus, and Bacillus subtilis was assessed using the bacterial growth inhibition method. An assessment was conducted to determine the susceptibility of silver nanoparticles to limit the growth of microorganisms, as well as to determine the lowest concentration required to achieve this inhibitory effect. Results: The results confirmed that the AgNPs were generated by the electrochemical method with the assistance of a PVA stabilizer. The nanosilver had a mean particle size of 53.1 nm. The antioxidant experiments revealed that PVA/AgNPs exhibit more antioxidant activity than ascorbic acid at higher dosages. PVA/AgNPs exhibit substantial antibacterial effectiveness. The minimum inhibitory concentration (MIC) of PVA/AgNPs against E.coli, S.enterica, S.aureus, and B.subtilis was found to be 12.5 μg/mL. Conclusion: The bioactive chemicals found on the surface of AgNPs are responsible for the antioxidant and antibacterial characteristics of electrochemical PVA/AgNPs composites.

Green Engineered CuO/SnO2/HNT Composites: Illuminating the Photocatalytic Path for Organic Pollutant Remediation and Zebrafish Embryo Toxicity Evaluation.

Photocatalysis stands out as a promising technique for treating organic contaminants, yet the quest for visible light active composite materials, crafted through cost-effective, eco-friendly, and uncomplicated processes, poses formidable challenges. Here, we introduce a successful endeavor, the synthesis of a CuO/SnO2 (CS) composite via a microwave method, employing Carissa edulis fruit extract as a reducing as well as capping agent. Various loadings of CS-HNT composites were prepared by ultrasonically incorporating CS onto nanotubular halloysite (HNT) clay. Employing a suite of types of characterization, including XRD, XPS, FT-IR, FE-SEM, HR-TEM, ζ potential, UV-vis-DRS, TGA, BET, and EIS, we meticulously explored the morphology, structure, stability, surface area, electrochemical, and optical properties of the developed CS-HNT composites. HR-TEM observations unveiled the formation of a heterojunction between cubic CuO and spherical SnO2 on the HNT clay surface. Optical and EIS analysis highlighted that the 20CS-HNT composite displayed significant absorption in the visible region, efficient electron-hole pair separation, and enhanced interfacial charge transport relative to other loadings. Photocatalytic evaluations and optimization studies revealed that the 20CS-HNT photocatalyst achieved notable removal efficiencies, eliminating 85% of Congo red (CR) and 80% of tetracycline (TC) within 90 min and 74% of ATZ in 3 h under visible light conditions. Scavenging investigations, the fluorescence probe method, and a NBT transformation study underscored the pivotal roles of hydroxyl and superoxide radicals in pollutant removal. The reusability trials highlighted the exceptional stability and recyclability of the photocatalyst, even after five cycles. In addition, zebrafish embryo toxicity tests revealed improved survival and hatching rates in photocatalyst-treated samples compared to those of controls. Moderate toxicity was observed in treated TC, while the treated CR sample showed non-lethal toxicity. In essence, this study unveils a straightforward and efficacious approach for developing photocatalysts for large-scale wastewater treatment. Furthermore, it proposes the adoption of safe clay-based bimetal oxide photocatalysts in diverse environmental applications.

Designing plausible catalysts for synthesis of zingerone from vanillin and acetone via aldol condensation reaction on O-terminated M3C2-MXenes

Herein, high-performance O-terminated M3C2 MXene catalysts were screened for the synthesis of zingerone using vanillin and acetone. The electrochemical and electronic properties of O-terminated ordered MXenes in the form of M3C2O2(H) [M = Ti, V, and Cr (3d); Zr, Nb, and Mo (4d); and Hf, Ta, and W (5d)] were investigated using first principle density functional theory (DFT) calculations. These calculations revealed 37 stable candidates based on their negative binding energy values of ΔG*H and three O-terminated M3C2 MXene candidates with superior zingerone synthesis activity than pure precious metal (platinum), a UL > −0.4 V can guarantee high activity and low energy consumption during zingerone synthesis. Ti3C2O (FCC)), Hf3C2O2 (HCPFCC), and Nb3C2O2 (HCPHCP) exhibited higher catalytic activity than other candidates, and their performances were competitive for zingerone synthesis, with low limiting potentials of −0.37, −0.27, and −0.35 V, respectively. Zingerone synthesis via the protolysis reaction between vanillin and acetone includes two paths, i.e., induced protolysis and direct protolysis via the aldol condensation reaction. Multiple descriptors were used to evaluate and screen promising candidates for the synthesis of zingerone. For example, ΔG(*vanillin*acetone), and Bader charge, and d-band center analyses revealed the origin of zingerone synthesis activity based on binding energy and electronic structure. Importantly, binding energy and electronic structure have a strong intrinsic linear scaling relationship that can be used to screen for the optimal catalyst by controlling the scaling relationship between the intermediate binding energy and electronic properties. Indicating a scaling relationship and volcano plot were established based on ΔG(*vanillin+*acetone) and ΔG[*zingiberone] depending on Limiting potential (UL). Finally, we proposed a method for directly inducing protolysis during the aldol condensation reaction, which may be widely applicable to different biomass-derived carbonyl compounds, yielding chemicals and medicinal compounds through biomass valorization.

Constructing Targeted Strong Nb4d-O2p-Li2s Configurations to Obtain Excellent Energy Density and Long Life for Li-Rich Cathodes.

The Li-rich Mn-based cathode materials (LMRs) deliver excellent energy density and exhibit low cost, which are considered as the most promising cathode materials for the next generation lithium-ion batteries. However, the irreversible redox reaction of the oxygen atoms directly leads to release oxygen and intensifies phase transformation. Besides, the local stress and strain will be generated due to the unit-cell volume difference between R-3m and C2/m phases, which continuously aggravates the collapse of secondary particles. Herein, the strong Nb4d-O2p-Li2s configurations at the Li1 sites of the TM-layer in the C2/m phase and secondary particles with the radial arrangement of refined primary particles are designed to inhibit oxygen release and relieve lattice stress by Nb2O5 treatment. Meanwhile, the preferential growth of the active {010} planes is presented to obtain an excellent transmission rate of Li+. As a result, the designed LMR delivers remarkable electrochemical properties with high discharge capacity and initial coulomb efficiency of 276 mAh g-1 and 85 % at 0.1 C, outstanding cycling retention rate of 81 % after 300 cycles. This novel crystal structure combining oxygen coordination regulation and micro-nano scale design provides inspiration for the design of high-performance LMRs.