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Mercury (Hg2+) as environmental pollutant is a widespread concern due to its cytotoxic effect in humans and animals and needs to be monitored through cost effective methods based on naked-eye detection. Herein, in this study, we extracted and isolated the limonin (LMN) via a facile procedure and then employed it as capping agent for the synthesis of silver nanoparticles (LMN-AgNPs) as a first report. LMN-AgNPs were characterized through Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), Dynamic Light Scattering (DLS), Zeta Potential Analyzer (ZPA) and Fourier Transform Infrared (FTIR) spectroscopy. As-formed LMN-AgNPs were recognized as extremely selective and highly sensitive colorimetric sensor for Hg2+ with potential analytical application. The developed sensor showed an outstanding linear correlation with the concentration of Hg2+ in the range of 0.002 − 55 µM via a color change from deep yellow to transparent showing hypsochromic-hypochromic shift with the limit of detection (LOD) and the limit of quantification (LOQ) as low as 0.21 nM and 0.7 nM respectively. The sensor was further allied with smartphone for immediate and on-site quantification of Hg2+. The LOD and LOQ of 0.42 µM and 1.4 µM was true for smartphone based sensing in the range of 7.5–55 µM Hg2+. The detection of Hg2+ was not disrupted by the presence of other metals in either of mentioned cases. The practical applicability of the proposed Hg2+ sensor was tested using spectrophotometric and smartphone based approaches in human serum and urine as well as in tap water samples with acceptable ranges of recovery. As-developed sensor can work as a potential candidate for monitoring of Hg2+ pollution in diverse fields of studies. [ABSTRACT FROM AUTHOR]

MXenes are emerging rapidly as promising electrode materials for energy storage due to their high electronic conductivity and rich surface chemistry, but their potassium storage performance is unsatisfactory because of the large size of K+ and irreversible interfacial reaction. Here, a developed 3D foam‐like MXene scaffold (3D‐FMS) is constructed via an electrostatic neutralization of Ti3C2Tx with positive‐charged melamine followed with calcination, which offers massive surface‐active sites and facilitates fast K+ transfer for boosting the potassium‐ion storage capacity and dynamics. In addition, using KFSI‐based electrolyte, the formation of a robust solid electrolyte interface layer with more inorganic components on MXene anode is revealed for enhancing the Coulombic efficiency. Consequently, the 3D‐FMS with KFSI‐based electrolyte delivers enhanced potassium‐ion storage performance in terms of capacity (161.4 mAh g−1 at 30 mA g−1), rate capability (70 mAh g−1 at 2 A g−1), and cycling stability (80.5 mAh g−1 at 1 A g−1 after 2000 cycles). Moreover, the assembled 3D‐FMS//activated carbon potassium‐ion hybrid supercapacitor delivers a high energy density of 57 Wh kg−1 at a power density of 290 W kg−1. These excellent performances demonstrate the great superiority of 3D‐FMS in KFSI‐based electrolyte and may accelerate the development of MXene‐based materials for potassium storage systems. [ABSTRACT FROM AUTHOR]

The research focuses on enhancing the energy storage capabilities of mesoporous silica (MCM-41) for supercapacitor applications. Electrodes made solely from MCM-41 do not possess the desired energy density required for electronic devices. To address this, combining ferrites with MCM-41 has been proposed as a means to enhance the electrochemical behavior. In this study, various contents of COF were loaded on MCM-41. Different characterization methods were used to study the physical and surface properties of the as synthesized materials like XRD, FTIR, SEM, TEM, EDX and SEM-mapping. TEM images confirmed that all the as-synthesized composites retained the mesoporous structure, and the particle size of ferrites ranged from 8 to 14 nm. The cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) techniques were employed to investigate the electrochemical characteristics of the composite materials in H2SO4 electrolyte solution (1.0 M) and a potential window ranging from 0.0 to 0.8 V. The results demonstrated that the incorporation of ferrites onto MCM-41 led to an elevation in specific capacitance, with the highest value (746 F.g−1) observed at 35 COF-MCM-41 composite. However, further increasing the content of ferrites resulted in a decrease in specific capacitance. Furthermore, the prepared composites exhibited excellent cycling stability even after 5000 cycles, with MCM-41, COF, and 35 COF-MCM-41 retaining 84.4%, 89.4%, and 94.8% of their initial specific capacitance, respectively. These findings highlight the significant role played by the dispersion of cobalt ferrite nanoparticles in enhancing pseudocapacitance behavior, thus improving the overall electrochemical performance of the composites. [ABSTRACT FROM AUTHOR]

Carbonaceous materials with closed pore structures have emerged as promising anodes for sodium-ion batteries. However, the rational design of closed pores and the investigation of their underlying sodium storage mechanisms face significant challenges. Herein, PVDF-derived pyrolytic carbon (PFC) with abundant open ultra-micropores and uniform pore size of 0.55 nm was chosen as the carbon matrix to construct a closed pore model to elucidate the sodium storage process in the closed pores. The transformation of ultra-micropores into closed pores was achieved with the assistance of polypropylene (PP), where the light aromatic compounds derived from PP can be deposited at the open pore entrance of the PFC during the pre-oxidation process, and subsequently pyrolyzed to a carbon layer in the carbonization stage, thus converting the open pores into closed pores. The obtained closed pore enriched carbon (PFCC@PP) showed a noticeable low-potential plateau region in the charge/discharge curve and an improved reversible capacity of 309.3 mA h g−1 with a high initial coulombic efficiency of 87.8%. When coupled with the O3-NaNi1/3Fe1/3Mn1/3O2 cathode, the assembled Na ion full cell realized a high energy density of 239.2 Wh kg−1 besides the remarkable rate capability. Additionally, theoretical calculations further validated the significant role of closed pores with optimal pore size in efficient Na ion storage. This work not only provides an interesting model for investigating closed-pore structures but also offers new insights into the rational design of carbon materials for advanced energy storage technology. [ABSTRACT FROM AUTHOR]

Sensitive and reliable detection of the amlodipine (AML) drug in biological and environmental samples poses a significant challenge, necessitating the development of innovative electrode platforms. Herein, efficient anodes (CuO@ITO) were constructed for the direct electrochemical detection of AML in phosphate buffer saline (PBS) by growing CuO nanostructures onto the ITO electrode. Controlled nucleation of Cu ions facilitated consistent structural growth over the ITO surface, resulting in close interfacial contact between the nanostructures and the current collector. The fabricated CuO@ITO anode exhibited remarkable electrochemical oxidation response toward AML, enabling sensitive detection within a dynamic concentration range of 0.1–1.6 µm using differential pulse voltammetry, with a detection limit of 0.014 µm. Additionally, the sensor demonstrated robust anti-interference capabilities against various biomolecules and pharmaceutical drugs, ensuring accurate and reliable AML detection even in complex biological samples. Satisfactory recoveries of spiked AML drug from human urine samples affirmed the sensor’s suitability for real-world applications. The overall findings of this work emphasize the significance of the developed sensor in enabling the sensitive and selective detection of AML, making it a valuable tool for clinical and environmental monitoring. [ABSTRACT FROM AUTHOR]

Potassium‐ion batteries (KIBs) have recently attracted considerable attention owing to their resource abundance, low cost and environmental friendliness. Graphite as a mature commercial anode material for lithium‐ion batteries, has been proved as a promising anode candidate for KIBs by reversible forming potassium‐graphite intercalation compounds. However, large volume expansion and sluggish K+ kinetics caused by the incompatibility between large radius of K+ and the small interlayer spacing of graphite, result in the poor cycle stability and rate performances, hindering its practical application. Extensive research efforts have focused on improving the potassium storage performance of graphite anodes. This review provides an overview of recent advances in addressing these challenges and optimizing the electrochemical performance of graphite anodes for KIBs. Various strategies to improve the electrochemical performance of graphite and graphitic carbon anodes, such as microcrystalline regulation, heteroatom doping, morphological adjustment, and coating modification, are discussed, while the critical issues and challenges associated with graphite anodes and the prospects for their advancement in KIBs are highlighted. The review offers valuable guidelines for rational structural design and promotes the commercial development of high‐performance graphite anode materials for KIBs. [ABSTRACT FROM AUTHOR]

This correction notice is for an article titled "3D prickle-like hierarchical NiO nanostructures with oxygen vacancies for electrochemical detection of enrofloxacin antibiotics" published in Applied Physics A: Materials Science & Processing. The correction addresses the incorrect figures that appeared in the article as Figs. 2 and 3b. The corrected figures show FE-SEM images of hierarchical NiO nanostructures and TEM images of NiO nanostructures with thistle-like growth. The correction also includes revised citations in the 2nd paragraph of Sect. 3.1. The original article has been corrected. [Extracted from the article]

Owing to unique physical and optical properties, fluorescent carbon dots (C-dots) are used in various biomedical applications. In this study, C-dots have been integrated as sensing agent on paper surface for colorimetric determination of clinically important analytes. Polyacrylamidebased C-dots coated C-dips showed visible color change from white to brown for iron (Fe2+, Fe3+) sample. Moreover, iron and copper (Cu2+) samples showed significant quenching of C-dots under UV. Images captured with/without UV were analyzed to study the relationship between different iron and copper concentrations and colorimetric intensity values. Color intensity and fluorescence showed a linear relationship with concentrations of iron and copper (Range: 1×10-4 to 1×10-2 M, Linearity: R² = 0.94). LOD from the paper sensor showed a sensitivity of 3.89×10-5 μM, 4.65×10-5 μM and 6.7×10-5 μM for Fe3+, Fe2+ and Cu2+ respectively, reflecting its reliability as low-cost sensing solution to analyze clinically relevant analytes as reported in current study. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDH) are regarded as attractive pseudocapacitive materials due to their impressive capacitive qualities that may be adjustable to their morphological features. However, the layered structure of LDH renders them susceptible to structural aggregation, which inhibits effective electrolyte transport and limits their practical applicability after limited exposure to active areas. Herein, we propose a simple template-free strategy to synthesize hierarchical hollow sphere NiMn-LDH material with high surface area and exposed active as anode material for supercapacitor application. The template-free approach enables the natural nucleation of Ni-Mn ions resulting in thin sheets that self-assemble into a hollow sphere, offering expended interlayer spaces and abundant redox-active active sites. The optimal NiMn-LDH-12 achieved a specific capacitance of 1010.4 F g−1 at a current density of 0.2 A g−1 with capacitance retention of 70% at 5 A g−1 after 5000 cycles with lower charge transfer impedance. When configured into an asymmetric supercapacitors (ASC) device as NiMn-LDH//AC, the material realized a specific capacitance of 192.4 F g−1 at a current density of 0.2 A g−1 with a good energy density of 47.9 Wh kg−1 and a power density of 196.8 W kg−1. The proposed morphological-tuning route is promising for designing template-free NiMn-LDHs spheres with practical pseudocapacitive characteristics. [ABSTRACT FROM AUTHOR]

The development of hydrogel electrolytes plays a critical role in high-performance flexible supercapacitor devices. Herein, a composite hydrogel electrolyte of polyacrylic acid (PAA) and graphene oxide (GO) has been successfully prepared, where the oxygen-containing functional groups of GO may crosslink and form hydrogen bonds with carboxyl on the molecular chain of PAA, thereby significantly enhancing the mechanical properties of a PAA-based gel electrolyte. The tensile strength increases from 4.0 MPa for pristine PAA gel to 6.1 MPa for PAA/GO composite gel, with the elongation at break rising from 1556% to 1950%. Meanwhile, GO promotes the transportation of electrolyte ions, which are favorable for enhancing the ionic conductivity of the PAA hydrogel. As a result, the assembled supercapacitor based on PAA/GO composite hydrogel electrolyte shows enhanced capacitance retention of 64.3% at a large current density of 20 A g−1 and excellent cycling stability over 10,000 cycles at 5 A g−1. Furthermore, the fabricated flexible supercapacitor devices could maintain outstanding electrochemical performance at various bending angles of 0–90°, indicating a promising prospect for the PAA/GO hydrogel electrolyte in flexible wearable fields. [ABSTRACT FROM AUTHOR]

2D MXenes have emerged as promising supercapacitor electrode materials due to their metallic conductivity, pseudo‐capacitive mechanism, and high density. However, layer‐restacking is a bottleneck that restrains their ionic kinetics and active site exposure. Herein, a carbon dots‐intercalated strategy is proposed to fabricate flexible MXene film electrodes with both large ion‐accessible active surfaces and high density through gelation of calcium alginate (CA) within the MXene nanosheets followed by carbonization. The formation of CA hydrogel within the MXene nanosheets accompanied by evaporative drying endow the MXene/CA film with high density. In the carbonization process, the CA‐derived carbon dots can intercalate into the MXene nanosheets, increasing the interlayer spacing and promoting the electrolytic diffusion inside the MXene film. Consequently, the carbon dots‐intercalated MXene films exhibit high volumetric capacitance (1244.6 F cm−3 at 1 A g−1), superior rate capability (662.5 F cm−3 at 1000 A g−1), and excellent cycling stability (93.5% capacitance retention after 30 000 cycles) in 3 m H2SO4. Additionally, an all‐solid‐state symmetric supercapacitor based on the carbon dots‐intercalated MXene film achieves a high volumetric energy density of 27.2 Wh L−1. This study provides a simple yet efficient strategy to construct high‐volumetric performance MXene film electrodes for advanced supercapacitors. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) is an excellent membrane-forming material with unique two-dimensional transport channels and excellent adsorption properties for heavy metal contaminants. However, swelling under cross-flow conditions and long-term water immersion leads to poor separation performances. To improve the stability of GO membrane materials, we propose a PVA-integrated graphene oxide/attapulgite membrane (GOAP) with a 3D microstructural arrangement of "brick–mortar-brick." The addition of PVA as mortar reinforces the strength of the structures via induced hydrogen bonding within the 3D water transport network. Furthermore, the Al2O3 ceramic substrate pre-treated with (3-aminopropyl) triethoxysilane (APTES) provided high mechanical stability to the composite membrane, extending the membrane's stability beyond a month of immersion without swelling or shedding. The PVA-integrated GO/ATP composite membrane maintained a rejection rate of 99% for Cu2+ solution (100 mg/L) in a 26-h continuous with nearly 100% rejection for various metals ions such as Cu2+, Ni2+, Pb2+, and Cd2+. The membrane exhibited a water flux of 20.7 L·m−2·h−1, which was 15.9-fold high than the pure GO membrane (GOM). The high water flux and heavy metal filtration rate with superior stability proved the practical suitability of the composite film for removing heavy metal ions. [ABSTRACT FROM AUTHOR]

Metal oxide-based electrochemical sensors, despite their robust redox activity, lack sufficient conductivity to overcome their sluggish kinetics. Herein, we propose a unique self-assembled hybrid configuration based on redox-active Co3O4 hexagons (Co3O4-HX) and the highly conductive, few-layer-thick Ti3C2Tx sheets. The self-assembly approach enabled the compact interfacial formation and moderate intercalation of Ti3C2Tx sheets, allowing the Co3O4/Ti3C2Tx composite (Co3O4–MX) to exhibit a synergetic improvement in the charge-transfer rate and oxidation current response toward isoprenaline (ISPT), a neurotransmitter drug. The hybrid composite when devised as an electrochemical sensor gives rise to a 7.9-fold higher oxidation current response to 0.65 μM ISPT than its pristine Co3O4 counterpart. The improved charge kinetics and generation of a superior oxidation current emphasized the critical role of Ti3C2Tx as an interactive substrate in the Co3O4–MX hybrid. The analytical detection capability assessed via differential pulse voltammetry (DPV) confirmed the sensor's high selectivity and marked stability both in low and high concentration ranges of ISPT ((0.01 to 0.33 μM) and 0.5 to 0.9 μM) with a limit of detection (LOD) of 3 × 10–3 μM (for low concentrations). Importantly, the fabricated sensor could detect ISPT from harsh biological environments such as human urine samples with a recovery rate of 99%. Moreover, the sensor exhibited a stable working response during its prolonged storage of 30 days in an aqueous PBS system. The proposed route of using MXenes as a conductive substrate paves the way for developing a robust metal-oxide-based redox-active hybrid system for the sensitive detection of important therapeutic compounds. [ABSTRACT FROM AUTHOR]

Improving metal oxides intrinsic electrochemical characteristics without altering their structural or compositional elements is a challenge, especially when designing a single component-based analytical sensor for monitoring emerging pollutants. Herein we propose the induction of oxygen vacancies in hierarchical NiO nanostructures using a simple wet-chemical reduction route to improve its inherent electrochemical redox characteristics. The synthesized NiO nanostructures possessed a thistle-like morphology with nanoprickles based structural features. The 3D prickle-like nanostructures with abundant surface-oxygen vacancies realized robust redox characteristics during the electrochemical oxidation of enrofloxacin (ENF) antibiotics. The existence of oxygen vacancies in NiO (ov-NiO NPKs) increased electrochemical conductivity and elevated redox activity, resulting in a 1.46-fold increase in the oxidation response of ENF compared to its non-vacancy counterpart. The ov-NiO NPKs based sensor showed an excellent linear working response for ENF in the concentration range of 0.001 to 0.15 µM, with a detection limit of 0.12 nM. Moreover, the sensor could effectively detect ENF from environmental samples with a high recovery rate confirming its suitability for practical applications. The suggested engineering of generating oxygen vacancies in metal oxides for improving intrinsic performance opens up new avenues for developing sophisticated single-platform-based sensors for rapid and efficient monitoring of emerging environmental contaminants. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) are regarded as a kind of promising candidate for large‐scale energy storage technology. The development of advanced carbon anodes with high Na‐storage capacity and initial Coulombic efficiency (ICE) from low cost, resources abundant precursors is critical for SIBs. Here, a carbon microcrystalline hybridization route to synthesize hard carbons with extensive pseudo‐graphitic regions from lignite coal with the assistance of sucrose is proposed. Employing the cross‐linked interaction between sucrose and lignite coal to generate carbon‐based hybrid microcrystalline states, the obtained hard carbons possess pseudo‐graphitic dominant phases with large interlayer spaces that facilitate Na ion's storage and transportation, as well as fewer surface defects that guarantee high ICE. The LCS‐73 with an optimum cross‐link demonstrates the highest Na‐storage capacity of 356 mAh g−1 and an ICE of 82.9%. The corresponding full‐cell delivers a high energy density of 240 Wh kg−1 (based on the mass of anode and cathode materials) and excellent rate capability of 106 mAh g−1 at 10 C in addition to outstanding cycle performance with 80% retention over 500 cycles at 2 C. The proposed work offers an efficient route to develop high‐performance, low‐cost carbon‐based anode materials with potential application for advanced SIBs. [ABSTRACT FROM AUTHOR]

Summary: Energy storage devices (ESD) are getting significant attention regarding their ability to reduce fossil fuel usage. Batteries and electrochemical supercapacitors are two well‐known ESDs with supercapacitors preferred for their high energy discharge potential. The metal oxides (MOs) with robust redox characteristics are ideal candidates for supercapacitors, although their capacitance still lacks behind the theoretical values. Here, partial reduced or oxygen‐deficient MOs have been identified have proven promising to reach the desired capacitance. The introduction of oxygen vacancies into MOs can effectively enhance their electrochemical properties without altering the inherent characteristics of MOs. This review discusses the recent progress on new oxygen‐deficient MOs and their performance as a supercapacitor. The importance of oxygen vacancy is described, followed by the traditional synthesis route to producing MOs. The present pathways for generating oxygen vacancies and their analytical assessment are covered in‐depth, followed by a section on the most advanced analytical techniques for detecting and interpreting the creation of such vacancies. The influence of oxygen vacancies on the supercapacitive performance of the most researched MOs is provided with the challenges and prospects of oxygen‐deficient MOs in supercapacitor application. [ABSTRACT FROM AUTHOR]

MXenes-Ti3C2Tx, based on their versatile surface characteristics, has rapidly advanced as an interactive substrate to develop electrochemical sensors for clinical applications. Herein, Ni embedded Ti3C2Tx (MX−Ni) composites were prepared using a self-assembly approach where Ti3C2Tx sheets served as an interactive conductive substrate as well as a protective layer to nickel nanoparticles (Ni NPs), preventing their surface oxidation and aggregation. The composite displayed a cluster-like morphology with an intimate interfacial arrangement between Ni, Ti3C2Tx and Ti3C2Tx-derived TiO2. The configuration of MX−Ni into an electrochemical sensor realized a robust cathodic reduction current against methylmalonic acid (MMA), a biomarker to vitamin B12 deficiency. The synergism of Ni NPs strong redox characteristics with conductive Ti3C2Tx enabled sensitive signal output in wide detection ranges of 0.001 to 0.003 µM and 0.0035 to 0.017 µM and a detection sensitivity down to 0.12 pM of MMA. Importantly, the sensor demonstrated high signal reproducibility and excellent operational capabilities for MMA in a complex biological matrix such as human urine samples. [ABSTRACT FROM AUTHOR]

MXenes have emerged as promising electrode materials for supercapacitors based on their metallic conductivity, good hydrophilicity, rich surface chemistry, and excellent mechanical characteristics. However, the strong interlayer van der Waals forces induce significant layer restacking, which restrict complete exposure of MXenes' surface active sites, impeding electron/ion transport and resulting in poor electrochemical performances. Herein, a porous MXene/carbon nanotube (CNT) film was prepared through a simple alkali-induced process. The developed porosity and the introduction of CNTs can effectively suppress the restacking of MXene nanosheets, promoting the effective utilization of the surface active sites of the MXene and facilitating fast ion/electron transportation. Consequently, the porous MXene/CNT film exhibited a high specific capacitance of 401.4 F g-1 at 1 A g-1 and a sustained capacitance of 336.2 F g-1 at an ultrahigh current density of 1000 A g-1, corresponding to an 83.8% capacitance retention. Furthermore, the film electrode demonstrated outstanding cycling stability, with a capacitance retention of 99.0% after 20,000 cycles at 100 A g-1, showing its significant potential for supercapacitor applications. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "Correction: Copper oxide-based anodes for highly sensitive electrochemical detection of amlodipine" published in the Journal of Materials Science: Materials in Electronics. The correction addresses an error in the Acknowledgements and Funding sections of the original article, where the grant number for King Saud University was incorrectly given as RSP2024R266 instead of RSP2024R79. The corrected sections now properly acknowledge the Researchers Supporting Project number (RSP2024R79) at King Saud University for funding the work. The publisher, Springer Nature, maintains a neutral stance on jurisdictional claims and institutional affiliations. [Extracted from the article]

A transparent and flexible polymer with unique electric and sound signal transmission capability under highly stretchable conditions has been synthesized. In this paper the milestone achieved in the polymerization of intrinsic ionic Ω--conjugated polymer, hereinafter known as Ionic Cables (ICs), through free radical crosslinking co-polymerization process/technique and structural modifications encountered so far in our experiments are discussed. EIS and stress-strain assessments had showed that ionic conductivity and flexibility are dependent on the amount of accelerator Tetramethylethylenediamine (TEMED) and curing time (CT). By varying the amount of accelerator, in our case TEMED, and CT the ICs with ionic conductivity of 0.021 S/cm to 0.111S/cmand 350% elongation to 448% elongation conditions was synthesized with highly water absorption capability up to 78% of its total volume. The synthesized ICs with ultra-stretchability, transparency and conductivity can be used in versatile applications, including stretchable ionic cables, tissue engineering, ionic mass transport systems and bio sensors. [ABSTRACT FROM AUTHOR]

MXenes have recently been recognized as potential materials based on their unique physical and chemical characteristics. The widely growing family of MXenes is rapidly expanding their application domains since their first usage as energy materials was reported in 2011. The inherent chemical nature, high hydrophilicity, and robust electrochemistry regard MXenes as a promising avenue for environment-remediation technologies such as adsorption, membrane separation, photocatalysis and the electrocatalytic sensor designed for pollutant detection. As the performance of MXenes in these technologies is on a continuous path to improvement, this review intends to cumulatively discuss the diversity and chemical abilities of MXenes and their hybrid composites in the fields mentioned above with a focus on MXenes improving surface-characteristics. The review is expected to promote the diversity of MXenes and their hybrid configuration for advanced technologies widely applied for environmental remediation. [ABSTRACT FROM AUTHOR]

This study presents the synthesis of CeO2-TiO2 nanocomposite and its potential application for the visible light-driven photocatalytic degradation of model crystal violet dye as well as real industrial waste water. The ceria-titania (CeO2-TiO2) nanocomposite material was synthesised using facile hydrothermal route without the assistance of any template molecule. As-prepared composite was characterised by SEM, TEM, HRTEM, XRD, XPS for surface features, morphological and crystalline characters. The formed nanostructures were determined to possess crystal-like geometrical shape and average size less than 100 nm. The as-synthesised nanocomposite was further investigated for their heterogeneous photocatalytic potential against the oxidative degradation of CV dye taken as model pollutant. The photo-catalytic performance of the as-synthesised material was evaluated both under ultra-violet as well as visible light. Best photocatalytic performance was achieved under visible light with complete degradation (100%) exhibited within 60 min of irradiation time. The kinetics of the photocatalytic process were also considered and the reaction rate constant for CeO2-TiO2 nanocomposite was determined to be 0.0125 and 0.0662 min−1 for ultra-violet and visible region, respectively. In addition, the as-synthesised nanocomposite demonstrated promising results when considered for the photo-catalytic degradation of coloured industrial waste water collected from local textile industry situated in Faisalabad region of Pakistan. Enhanced photo-catalytic performance of CeO2-TiO2 nanocomposite was proposed owing to heterostructure formation leading to reduced electron-hole recombination. [ABSTRACT FROM AUTHOR]

Since the emergence of zero waste concept, efficient waste recycling system and recovery of energy from the waste materials become challenging tasks globally. Municipal solid waste (MSW) is considered as one of a potential sources of energy. In the present study, bio-compactable iron oxide (Fe3O4) nanoparticles (NPs) were synthesized by hydrothermal method. These NPs were characterized by using atomic force microscopy (AFM), energy dispersive x-ray (EDX), and scanning electron microscopy (SEM) for size determination and surface morphology. The organic fraction of MSW (OFMSW) such as food waste (FW) was utilized as a substrate in this study. The anaerobic digestion of OFMSW in batch test was carried out under mesophilic temperature (37 ± 0.5°C). Four different concentrations of Fe3O4NPs i.e 50mg/L, 75mg/L, 100mg/L, and 125mg/L were added in each batch test. It was observered that 75mg/L yielded maximum CH4and followed by 50mg/L. [ABSTRACT FROM PUBLISHER]

This study describes the development of an electrochemical sensor system for the determination of bisphenol A using tannic acid functionalized CuO nanoglobules. The utilized tannic acid acted simultaneously as both bio-compatible template and functionalizing agent for the as-synthesised CuO nanostructures. The excellent synergy of high surface area and favorable interactions between the moieties of tannic acid and bisphenol A molecules enabled sensitive electrochemical oxidation of bisphenol A within wide detection window (0.1–5.5 µM) and limit of detection estimated to be 0.01 µM. Moreover, the sensor exhibited satisfactory stability and strong anti-interference capability when evaluated against common interferents molecules such as phenol, hydroquinone, and 4-nitrophenol. [ABSTRACT FROM PUBLISHER]

This study describes the development of a new ITO-based electrode used for the electrochemical determination of N-acetyl-l-cysteine (NAC). The electrode system relies on in situ grown CuO nanostructures over the ITO substrate, which provide a relatively greater contact and enables effective electron facilitation during the electrocatalytic oxidation of NAC in an aqueous medium. In situ growth of the CuO nanostructures was achieved using a simple hydrothermal process with the application of succinic acid as an effective growth template. The grown layer of CuO possessed a dense population of highly ordered nanostructures with a high degree of structural uniformity. The study evaluates the potential of the newly developed ITO-based electrode against the bare GCE and an electrode modified via the direct deposition of the same CuO nanostructures synthesised under similar hydrothermal conditions. The electrochemical oxidation of NAC over the newly developed electrode demonstrated low-over potential value and good working linearity in the range from 0.01 to 0.28 μM. The electrode system was found to be sensitive up to 1.2 × 10−3μM (S/N = 3) with charge transfer co-efficient (α) and diffusion co-efficient (D) values of 0.65 and 1.62 × 10−2 cm2 s−1, respectively. Moreover, the developed electrode system demonstrated excellent working capability when utilised for the determination of NAC from a pharmaceutical formulation obtained from a local pharmacy. [ABSTRACT FROM AUTHOR]

This work describes the fabrication of unique arrow head shaped CuO nanostructures using simple hydrothermal treatment method. The highly attractive features were obtained by the application of glutaric acid utilised simultaneous as template and functionalising agent. The functionalised nanostructures were known to possess excellent potential towards the electro-catalytic oxidation of carbofuran pesticide. The generated intense electrochemical signal with lower potential value enabled sensitive and selective determination of carbofuran up to 1×10−3 µM with wide sensing window in range of 0.01 to 0.16 µM. The feasibility of the developed sensor system for the practical application was also studied by testing its potential in real sample extracts of various vegetables. The excellent recoveries demonstrated the analytical robustness of the developed sensor system. The sensor system utilises a new and simple approach towards sensitive determination of toxic pesticides reflecting its wide spectrum application in various fields. [ABSTRACT FROM AUTHOR]

The study describes the application of oxidation resistant copper nanostructures as an efficient heterogeneous catalyst for the treatment of organic dye containing waste waters. Copper nanostructures were synthesized in an aqueous environment using modified surfactant assisted chemical reduction route. The synthesized nanostructures have been characterized by UV-Vis, Fourier transform infrared spectroscopy FTIR spectroscopy, Atomic force microscopy (AFM), Scanning Electron Microscopy (SEM), and X-ray diffractometry (XRD). These surfactant capped Cu nanostructures have been used as a heterogeneous catalyst for the comparative reductive degradation of methyl orange (MO) in the presence of sodium borohydride (NaBH4) used as a potential reductant. Copper nanoparticles (Cu NPs) were found to be more efficient compared to copper nanorods (Cu NRds) with the degradation reaction obeying pseudofirst order reaction kinetics. Shape dependent catalytic efficiency was further evaluated from activation energy (EA) of reductive degradation reaction. The more efficient Cu NPs were further employed for reductive degradation of real waste water samples containing dyes collected from the drain of different local textile industries situated in Hyderabad region, Pakistan. [ABSTRACT FROM AUTHOR]

The aim of this study was to reduce the highly toxic hexavalent chromium Cr(VI) into less toxic chromium Cr(III) species by using nickel nanoparticles (Ni NPs) as catalysts in order to provide safety to the aqueous environment. In the first phase Ni NPs were synthesized in ethylene glycol and capped with 1-cysteine by a modified microwave irradiation method using NaOH as the accelerator. The formed Ni NPs were characterized by various techniques such as UV-Visible spectroscopy, Fourier Transform Infra-red (FTIR) spectroscopy and Scanning Electron Microscopy (SEM). In the second phase the formed Ni NPs were immobilized on glass surfaces and employed as catalyst for the reduction of Cr(VI) ions. According to observations, 99% reduction of Cr(VI) ions was achieved in the presence of 0.5 mg of Ni NPs catalyst in just five minutes as compared to nickel powder that showed only 16% reduction in 15 minutes. The study has a great impact on the aqueous pollution control of Cr(VI) especially caused by the discharge of waste water from several industries utilizing Cr(VI) containing salt as one of the essential gradients. [ABSTRACT FROM AUTHOR]

Procalcitonin (PCT) protein has recently been identified as a clinical marker for bacterial infections based on its better sepsis sensitivity. Thus, an increased level of PCT could be linked with disease diagnosis and therapeutics. In this study, we describe the construction of the photoelectrochemical (PEC) PCT immunosensing platform based on it situ grown photo-active CuWO4 nanospheres over reduced graphene oxide layers (CuWO4@rGO). The in situ growth strategy enabled the formation of small nanospheres (diameter of 200 nm), primarily composed of tiny self-assembled CuWO4 nanoparticles (2–5 nm). The synergic coupling of CuWO4 with rGO layers constructed an excellent photo-active heterojunction for photoelectrochemical (PEC) sensing. The platform was then considered for electrocatalytic (EC) mechanism-based detection of PCT, where inhibition of the photocatalytic oxidation signal of ascorbic acid (AA), subsequent to the antibody–antigen interaction, was recorded as the primary signal response. This inhibition detection approach enabled sensitive detection of PCT in a concentration range of 10 pg·mL−1 to 50 ng.mL−1 with signal sensitivity achievable up to 0.15 pg·mL−1. The proposed PEC hybrid (CuWO4@rGO) could further be engineered to detect other clinically important species. [ABSTRACT FROM AUTHOR]