Hydrothermal Route Research Articles

Semiconductor-bimetallic plasmonic heterojunction ZnO-Ag-Cu as reusable SERS substrate with attomolar detection limit.

Semiconductor-bimetallic ZnO-Ag-Cu (ZAC) heterojunction of different compositions were fabricated as highly sensitive SERS substrates. ZnO nanorods were synthesized using a facile hydrothermal route. ZAC composites were synthesized via impregnation method by keeping ZnO content same and varying the mole fractions of Ag and Cu. The ZnO matrix, known for its stability and photocatalytic properties, was decorated with Ag and Cu nanoparticles to enhance plasmonic activity and boost SERS. Introducing semiconductor oxide as SERS substrate reduces the substrate cost due to its self-cleaning property upon exposure to UV light. When SERS activity of ZAC composites were compared with either ZnO-Ag (ZA) or ZnO-Cu (ZC) composites, the best SERS performance was recorded with ZAC55, where the Ag and Cu content are same. ZAC55 produced a SERS enhancement factor of 6.2 × 10⁶ and a limit of detection of 10-18 M 10-15 M for the analyte molecules Rhodamine 6G (R6G) and Methylene Blue (MB), respectively, using 532 nm laser excitation. The enhanced SERS performance is attributed to the synergistic effects of ZnO, Ag, and Cu, unveiling ZAC55 as a promising next-generation SERS substrate. Along with remarkable sensitivity, ZAC55 showed promising reusability and reproducibility, indicating its potential for practical applications in chemical sensing.

Improving Charge Transfer Kinetics of Ni Hydroxide Through Chromium: Efficient Production of Benzoic Acid at Ampere-Level Current Density.

Hybrid water electrolysis with the simultaneous generation of hydrogen and value-added chemicals enhances the viability of the water electrolysis process. A remarkably high current density of 1.4 A cm-2 toward benzyl alcohol oxidation (BOR) at a low potential of 1.45V reported in this work suggests that the oxygen evolution reaction (OER) can be replaced with BOR by selecting a suitable catalyst. A chromium oxide-treated Ni foam (Cr-NF) synthesized through a simple hydrothermal route offers 100% conversion and 99.5% faradaic efficiency toward benzoic acid. The surface nature of NF is significantly modified by chromium oxide, known for its hydrophilic nature and pore-forming abilities, resulting in enhanced active sites. In situ Raman analysis confirms the reversible electrochemical conversion of Ni hydroxides to NiOOH, which converts benzyl alcohol (BA) to benzoic acid (PhCOOH) by chemical oxidation. The theoretical analysis suggests accelerated electronic transport and lower free energy for the sorption of intermediates utilizing the Cr2O3/NiOOH surface. In a two-electrode arrangement, Cr-NF demonstrates excellent performance, achieving a current density of 2.5 A cm-2 at an applied potential of 3.1V, which is highly significant compared to OER-based systems. This system can further be studied for commercial applications.

Biomimetics‐Driven Design of Micron‐Sized SiO Composites for High‐Performance Lithium‐Ion Batteries

AbstractMicron‐sized SiO‐based materials have attracted extensive attention in lithium‐ion batteries due to high theoretical capacity and low‐cost. However, their development is seriously hampered by the large volume change and low conductivity of SiO. Herein, by combining the theoretical prediction with biomimetics‐driven design concept, a unique chloroplast‐like SiO@N‐doped carbon‐carbon coated SnO2 (denoted as SiO‐NC@SnO2‐C) integrative composite is presented through a facile one‐pot hydrothermal route. The resultant SiO‐NC@SnO2‐C anode for lithium‐ion storage shows a high reversible capacity of 1209 mA h g−1 at 0.2 A g−1 after 160 cycles and an outstanding rate capability of 722.7 mA h g−1 at 5 A g−1. In situ TEM technique and cross‐sectional SEM images reveal that the cavity formed in the composite, the flexible carbon interlayer, and glucose‐derived carbon outer layer together play crucial roles in alleviating the volume expansion and improving the structural stability of the electrode. In situ Raman spectra further verify that the highly reversible structure of SiO‐NC@SnO2‐C is responsible for its superior stability. Importantly, the SiO‐NC@SnO2‐C composite also shows an excellent reversible lithium storage capacity of 92.9 mA h g−1 with a 73% of capacity retention after 100 cycles at 1 C in full‐cells.

Highly efficient visible-light-driven S-scheme graphene bridged MoS2/Co3O4 nanohybrid for the photocatalytic performance of hazardous dye and antibacterial activity.

A novel graphene-bridged MoS2/Co3O4 (MCG) nanohybrid was well fabricated by a hydrothermal route. The purpose of valuable and economical S-scheme systems with vigorous interface interactions is pressing to photocatalytic efficiency and efficient utilization. While mighty progress has been created with respect to charge carrier bridges, the charge transferring ability of the facility charge carrier bridges is far from capable owing to lower electrical conductivity. The photocatalytic antibacterial tests were performed with visible light activity, and the results exhibited that the as-prepared MCG nanohybrid with powerful interfacial coupling presented excellent photodegradation performance in comparison with bare MoS2 and Co3O4 samples for the removal of methylene blue (MB) and E-coli with visible light irradiation. In addition, a better photocatalytic MB capability and antibacterial activity of 99.5 % and 100 % are approached through MCG-4 nanohybrid, which is 2.76 and 8.32 folds higher than that of the pristine MoS2 sample. The PL measurements and EIS analysis also illustrated that MCG-4 nanohybrid possesses a great separation efficiency of photoinduced charge carriers. This work provides a new objective for high-potential S-scheme photocatalysts and their utilization in the field of environmental remediation.

Performance of Graphene Oxide-Supported Co₃O₄ with Assisted Urea as Electrocatalysts for Oxygen Reduction Reaction in PEMFCs

In this work, cobalt oxide (Co3O4) nanoparticles supported on a graphene oxide (GO) electrocatalyst were synthesized using a simple and low-cost hydrothermal route for oxygen reduction reaction (ORR) in fuel cells. The effects of varying the urea concentration on the physicochemical and electrochemical characteristics were investigated in alkaline media using field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), Raman spectroscopy, cyclic voltammetry (CV), linear sweep voltammetry (LSV), and chronoamperometry. The electrocatalyst prepared using cobalt acetate tetrahydrate and urea with a molar ratio of 1:1 exhibited the best ORR activity where the highest onset potential (Eonset) at 0.88 V through four-electron mechanism at 25 °C. The synthesized electrocatalyst also showed improved stability compared with Pt/C. Although CN1-1 exhibits a lower power density (37.9 mW cm⁻2) compared to Pt/C (173.6 mW cm⁻2), it is still expected to be suitable as an ORR electrocatalyst for proton exchange membrane fuel cells (PEMFCs).

Decoding Anionic Organization of Hydroxide-Fluorides in a Diaspore-Type Network.

The diaspore-type crystalline structure is historically well-known in mineralogy, but it has also been widely studied for various applications in the field of catalysis, electrocatalysis, and batteries. However, once two anions of similar ionic size but different electronegativity, such as F- and O2- or more precisely OH-, are combined, the knowledge of the location of these two anions is of paramount importance to understand the chemical properties in relation with the generation of hydrogen bonds. Coprecipitation and hydrothermal routes were used to prepare hydroxide-fluorides that crystallize all in an orthorhombic structure with four formula units per cell. By coupling X-ray scattering techniques for both long- and short-range order (XRD and PDF) and by using multiple complementary spectroscopic probes (Raman, FTIR, and 1D/2D 19F and 1H MAS NMR measurements), preferential anionic site occupancy by hydroxyl groups and fluoride ions is demonstrated. Moreover, in the Mg(OH)F diaspore network, 10% of Mg2+ is located in the tunnels, resulting in cationic vacancies in the main site. The preference for OH at the edges is clearly marked in the case of Mg(OH)F, whereas OH is preferred at the vertices in Zn(OH)F, regardless of the allotropic form. The dominant polar low-symmetry Pna21 form of Zn(OH)F has more OH groups at the vertices than the parent centrosymmetric Pnma variety, in agreement with its strongest hydrogen bonds. Given the remarkable flexibility of the diaspore-type network, the thermal stability of these hydroxide-fluorides is perfectly matched to the structural characteristics. The location of anionic groups within the diaspore framework should play a key role in understanding and optimizing physicochemical properties such as proton mobility for alkaline batteries and acid-base properties for heterogeneous catalysis.

Highly Green Fluorescent Carbon Dots from Gallic Acid: A Turn-On Sensor toward Pb2+ Ions.

Carbon dots (CDs) are emerging novel fluorescent sensing nanomaterials owing to their tunable optical properties, biocompatibility, and eco-friendliness. Herein, we report a facile one-pot hydrothermal route for the synthesis of highly green fluorescent CDs using gallic acid (GA) as a single carbon source in N,N-dimethylformamide (DMF) solvent, which serves as a nitrogen source and reaction medium. The optical properties of the synthesized GA-DMF CDs were systematically characterized by using UV-vis and photoluminescence spectroscopy, revealing strong green fluorescence. Further, to gain insights into their size and structural, elemental, and chemical composition, Fourier transform infrared, dynamic light scattering, high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction, and X-ray photoelectron spectroscopy characterization techniques were performed. HR-TEM analysis confirmed the formation of uniformly spherical GA-DMF CDs with an average particle size of 16 ± 6.1 nm. Notably, the GA-DMF CDs exhibited a highly selective and turn-on fluorescent response to Pb2+ ions in aqueous solutions, which was attributed to a chelation-enhanced fluorescence mechanism. The detection limit for Pb2+ ions was determined to be as low as 7.15 × 10-7 M, with a broad linear detection range of 30-130 μM, underscoring their sensitivity and practical application in water quality monitoring. This study introduces a novel, sustainable approach for synthesizing nitrogen-doped CDs with outstanding optical properties and highlights their unprecedented selectivity toward Pb2+ ions, advancing the development of efficient and eco-friendly sensing platforms for heavy metal detection.

Hierarchical MoS2@NiFeCo-Mo(doped)-Layered Double Hydroxide Heterostructures as Efficient Alkaline Water Splitting (Photo)Electro-catalysts.

Designing cost-effective electrocatalysts with fast reaction kinetics and high stability is an outstanding challenge in green hydrogen generation through overall water splitting (OWS). Layered double hydroxide (LDH) heterostructure materials are promising candidates to catalyze both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), the two OWS half-cell reactions. This work develops a facile hydrothermal route to synthesiz hierarchical heterostructure MoS2@NiFeCo-LDH and MoS2@NiFeCo-Mo(doped)-LDH electrocatalysts, which exhibit extremely good OER and HER performance as witnessed by their low IR-corrected overpotentials of 156 and 61 mV with at a current density of 10mA cm-2 under light assistance. The MoS2@NiFeCo-Mo(doped)-LDH-MoS2@NiFeCo-LDH OWS cell achieves a low cell voltage of 1.46V at 10mA cm-2 during light-assisted water electrolysis. Both materials exhibited exceptional stability under industrially relevant HER and OER conditions, maintaining a current density of 1A cm-2 with minimal alterations in their potential and performance. The experimental and computational results demonstrate that doping the LDH matrix with high-valence Mo atoms and MoS2 quantum dots improves the electrocatalytic activity by 1) enhancing electron transfer, 2) making the electrocatalyst metallic, 3) increasing the number of active sites, 4) lowering the thermodynamic overpotential, and 5) changing the OER mechanism. Overall, this work develops a facile synthesis method to design highly active and stable MoS2@NiFeCo-Mo(doped)-LDH heterostructureelectrocatalysts.

Photocatalytic removal of synthetic dyes using Bi2O3–TiO2 nanocomposites obtained by simple hydrothermal route

This study describes the preparation of TiO2-modified Bi2O3 photocatalysts with different TiO2 contents, synthesized via an in situ hydrothermal method. The powder samples were characterized by XRD, SEM, TEM, FTIR–ATR, UV–Vis, XPS, and N₂ physisorption analysis. The photocatalytic activity of the TiO2-modified Bi2O3 was studied for the removal of methyl orange (MO) and methylene blue (MB) under different reaction conditions. The TiO2-modified Bi2O3 photocatalysts exhibited superior photocatalytic activity compared to the pristine samples of TiO2 and Bi2O3. The BiT16 sample achieved degradation rates of approximately 93.9% and 98.2% for MO and MB, respectively, within 120 min of reaction at 30 ppm. These results are attributed to the band gap values, differences in textural features, TiO2 content, and the reduction in the recombination process of e⁻/h⁺ pairs in the Bi2O3–TiO2 composites. Reaction kinetics were determined using the Langmuir–Hinshelwood mechanism, and during the third photoreaction cycle, the TiO2-modified Bi2O3 (BiT16) achieved photocatalytic degradation rates of 65.6% for MO and 70.5% for MB.

Phase Engineering of SnSeX (X = 1,2) Microstructures for High-Performance NO2 Chemiresistive Room-Temperature Sensor Systems: Toward Highly Reliable and Robust Detection Properties under Humidity and Interfering Gas Conditions.

Two-dimensional SnSeX (X = 1, 2) has emerged as a promising candidate for a NO2 chemiresistive sensor due to a remarkable affinity to NO2 gas adsorption. Although their gas sensing mechanism primarily relies on direct charge transfer, the underlying mechanisms of SnSe and SnSe2 remain unclear, despite various reported successes in phase engineering of SnSeX. Here, we investigate phase engineering of SnSeX in a hydrothermal route via 1-dodecanethiol (1-DDT), which served as a phase stabilizer, and comprehensively demonstrate phase-dependent NO2 detection properties. As the 1-DDT concentration increases, we directly confirm that the SnSe structure was gradually transformed to the SnSe2 one. This transformation correlates with a gradual increase in NO2 gas responses from 45 to 1430%, the highest value reported among SnSeX-based NO2 gas sensors. The obtained SnSe2-based sensors also exhibit a good NO2 discrimination without configuration of sensor arrays, under an interfering gas atmosphere in humidity conditions. Our computational calculation also unveils that these outstanding detection performances are attributed to well-constructed SnSe2 coupled with a single Se vacancy to enhance a stronger NO2 adsorption than SnSe. Finally, we demonstrate a sensor module system based on SnSe2, enabling real-time monitoring of NO2 gas.

Influence of Synthesis Conditions on the Capacitance Performance of Hydrothermally Prepared MnO2 for Carbon Xerogel-Based Solid-State Supercapacitors.

In this study, the potential to modify the phase structure and morphology of manganese dioxide synthesized via the hydrothermal route was explored. A series of samples were prepared at different synthesis temperatures (100, 120, 140, and 160 °C) using KMnO4 and MnSO4·H2O as precursors. The phase composition and morphology of the materials were analyzed using various physicochemical methods. The results showed that, at the lowest synthesis temperature (100 °C), an intercalation compound with composition K1.39Mn3O6 and a very small amount of α-MnO2 was formed. At higher temperatures (120-160 °C), the amount of α-MnO2 increased, indicating the formation of two clearly distinguished crystal structures. The sample obtained at 160 °C exhibited the highest specific surface area (approximately 157 m2/g). These two-phase (α-MnO2/K1.39Mn3O6) materials, synthesized at the lowest and highest temperatures, respectively, and containing an appropriate amount of carbon xerogel, were tested as active mass for positive electrodes in a solid-state supercapacitor, using a Na+-form Aquivion® membrane as the polymer electrolyte. The electrochemical evaluation showed that the composite with the higher specific surface area, containing 75% manganese dioxide, demonstrated improved characteristics, including 96% capacitance retention after 5000 charge/discharge cycles and high energy efficiency (approximately 99%). These properties highlight its potential for application in solid-state supercapacitors.

Hierarchical tungsten oxide flower-rod architectures synthesized by hydrothermal route and its applications in electrochromism

Hierarchical tungsten oxide flower-rod architectures synthesized by hydrothermal route and its applications in electrochromism

Fluorescence tunable carbon dots for in vitro nuclear dynamics and gastrointestinal imaging in live zebrafish and their in vivo toxicity evaluation by cardio-craniofacial disfunction assessment.

Sub-cellular organelle anomalies are frequently observed in diseases such as cancer. Early and precise diagnosis of these alterations can be crucial for patient outcomes. However, current diagnostic tools using conventional organic dyes or metal quantum dots face limitations, including poor biocompatibility, stringent storage conditions, limited solubility in aqueous media, and slow staining speeds. These challenges underscore the need for safer, more effective diagnostic and therapeutic solutions. In these aspects, we have developed highly photostable, biocompatible, water-dispersible carbon dots (TNCDs) with an average size of 5.5 nm using tartaric acid and ethylenediamine via a hydrothermal route. The synthesized TNCDs have shown bright blue fluorescence under the irradiation of UV-light at an excitation wavelength of 365 nm. They exhibit a quantum yield (QY) of 25.1% with maximum emission at 390 nm. A nice tri-exponential fitting of the decay curve with characteristic lifetimes of 1.52 ns, 3.05 ns and 6.11 ns for TNCDs was obtained. In vitro studies demonstrated that TNCDs have high biocompatibility (20 μg ml-1) with almost 100% cell viability and excellent nucleus targeting and staining capabilities with low background interference (with 10-12 times enhancement in fluorescence intensity). Additionally, if tagged with photosensitizers or radionuclides, TNCDs can serve as therapeutic agents in photodynamic therapy against cancer cells. Importantly, TNCDs exhibited negligible toxicity in developing zebrafish even at high concentrations (up to 400 mg L-1) as investigated by cardio and craniofacial disfunction assessment. Live organism imaging revealed that TNCDs produced aggregation-induced strong and specific green fluorescence in the gut of zebrafish larvae even at low concentrations, indicating their potential for nucleus staining and gut-specific optical imaging (at 50 mg L-1). Thus, our TNCDs represent a robust nanoplatform for cellular and whole-organism fluorescence imaging, offering both diagnostic and therapeutic potential.

Hierarchical Self-Assembly of SnO2 Nanoparticles into Porous Microspheres: Exceptionally Selective Ammonia Sensing at Ambient.

Herein, porous SnO2 microspheres in a three-dimensional (3D) hierarchical architecture were successfully synthesized via a facile hydrothermal route utilizing d-(+)-glucose and cetyltrimethylammonium bromide (CTAB), which act as reducing and structure-directing agents, respectively. Controlled adjustment of the CTAB to glucose mole ratio, reaction temperature, reaction time, and the calcination parameters all provided important clues toward optimizing the final morphologies of SnO2 with exceptional structural stability and reasonable monodispersity. Electron microscopy analysis revealed that microspheres formed were hierarchical self-assemblies of numerous primary SnO2 nanoparticles of ∼3-8 nm that coalesce together to form nearly monodispersed and ordered spherical structures of sizes in the range of 230-250 nm and are appreciably porous. N2-sorption measurements further confirmed the high degree of porosity for these structures, with an estimated BET surface area of ∼35 m2 g-1. Taking advantage of these porous structures and large surface area, the ammonia (NH3) sensing capabilities of the SnO2 spheres were explored. The gas sensor exhibited a notable response value (S) of ∼20.72 when exposed to 100 ppm of NH3 gas, all while operating at room temperature (∼27 °C), along with an impressively low detection limit of ∼1 ppm. Based on the comprehensive investigations, the potential mechanism behind the formation of these intricate SnO2 hierarchical structures along with the factors that make this material exhibit such excellent gas sensing behavior is postulated. Overall, the work provides a facile and possibly a generic route for the synthesis of hierarchical nanostructured materials that holds promise for the development of ultrasensitive gas sensor materials operating at room temperature.

Development of nitrogen and phosphorus dual-doped reduced graphene oxide from waste plastic for supercapacitor applications: Comparative electrochemical performance in different electrolytes

The persistent non-biodegradable nature of plastic highlights the urgent need for effective waste management and resource conservation, underscoring the crucial importance of recycling and upcycling within a cradle-to-cradle framework. This research introduces an eco-friendly and straightforward upcycling process for plastic waste, which produces significant quantities of reduced graphene oxide through a carefully designed 2-stage pyrolysis method. To enhance the electrochemical properties of the reduced graphene oxide, they were doped with heteroatoms (i.e. nitrogen and phosphorus) via a hydrothermal route. Also, as the nature of the electrolyte plays a significant role in electrochemical analysis, a comparative evaluation of the supercapacitive performance of the heteroatom-doped reduced graphene oxide was conducted across various aqueous electrolytes, including 1 M H2SO4, 6 M KOH, and 2 M KCl, as well as hydrogel polymer electrolytes such as 1 M H2SO4/1 M PVA, 2 M KCl/1 M PVA, and 6 M KOH/1 M PVA. Our results demonstrate that synthesized material from waste plastic exhibits excellent performance, particularly when combined with a 1 M H2SO4 electrolyte, achieving the highest specific capacitance of 407.6 F/g. In conclusion, this study presents a cost-effective and sustainable approach to promoting a circular economy by repurposing waste plastic for energy storage applications.

A high-capacity double-layered (NH4)0.5V2O5 in micro-rods structure for sodium storage

An ammonium vanadium bronze (NH4)0.5V2O5 (NVO) was synthesized via a hydrothermal route and investigated the Na-insertion/extraction process as a cathode for Na-ion batteries. The structural analysis confirms that the double-layered NVO in the micro-rods structure is formed by the double-sheet [VO6] with a large distance interlayer of 9.717 Å to be suitable for reversible Na-storage. The charge–discharge cycling performance delivers ∼160 mAh/g for long-term 200 cycles with structural stability. The ex-situ EXD at various Na-content states demonstrates the shrinkage/expansion of the interlayers during Na-migration, and the NH4+-ions play an essential role as the “pillar” of double-layered V2O5 to assure cycling stability. This work contributes to a high-capacity member of the V2O5 polymorph family in the context of Na-ion batteries.

Hydride-reduction-induced oxygen vacancies in CoV2O6 for machine learning-assisted enhanced electrochemical detection of homovanillic acid

Enhancing the intrinsic properties of metal oxides without relying on external modifiers remains challenging for achieving improved electrochemical response and reducing sensor fabrication costs. Herein, a simple hydride-reduction route is adopted to integrate oxygen vacancies in cobalt vanadium oxide (CoV2O6) microspheres to improve its electrochemical oxidation towards homovanillic acid (HVA), a cancer biomarker. CoV2O6 prepared via hydrothermal route, when systematically exposed to varying concentrations of NaBH4, generates abundant oxygen vacancies. A systematic comparison of CVO and CVOv confirms that vacancies are critical in improving catalytic sites and charge transferability during HAV oxidation in PBS (0.1 M) (pH 6.5). Differential pulse voltammetry (DPV)-based sensing confirms the sensor’s excellent workability in the low concentration range of 0.15 to 4.0 uM with a low LOD of 0.03 uM HAV in PBS (0.1 M). Moreover, the sensor exhibits high selectivity towards HAV, even in common interferents. Machine learning (ML)-based algorithms validated the sensor’s performance, and the comparative evaluation showed that artificial neural network (ANN) outperformed others in interpreting DPV data, achieving a minimal mean absolute error (MAE) of 0.2927, in contrast to 0.8475 for LightGBM and 0.8785 for support vector machine (SVM), thereby confirming its enhanced accuracy in predicting HVA concentration.Please check the edits made to the article title and amend if necessary.thank youPlease confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author Given name: [Razium Ali] Last name [Soomro]. Also, kindly confirm the details in the metadata are correct.thank you

Preliminary mechanistic insights into the detection of ethanol vapour using MnO2 NRs-CNPs-poly-4-(vinylpyridine) based solid-state sensor operating at room temperature.

Semiconductor metal oxide gas sensors are widely used to detect ethanol vapours, commonly used in industrial productions, road safety detection, and solvent production; however, they operate at extremely high temperatures. In this work, we present manganese dioxide nanorods (MnO2 NRs) prepared via hydrothermal synthetic route, carbon soot (CNPs) prepared via pyrolysis of lighthouse candle, and poly-4-vinylpyridine (P4VP) composite for the detection of ethanol vapour at room temperature. MnO2, CNPs, P4VP, and MnO2 NRs-CNPs-P4VP composite were characterised using scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and Raman spectroscopy. Five sensors were prepared, namely, sensor 1 (MnO2 -NRs), sensor 2 (CNPs), sensor 3 (CNPs-P4VP composite of a mass ratio of 1:3), sensor 4 (MnO2 NRs-CNPs-P4VP composite of a mass ratio 1:1:3), and sensor 5 (MnO2 NRs-CNPs-P4VP composite of a mass ratio 2:1:3). All the five sensors were used detect to 2-propanol, acetone, ethanol, methanol, and mesitylene vapours at room temperature, but among all the tested sensors, sensor 4 was highly sensitive to ethanol vapour and less sensitive to 2-propanol, methanol, acetone, and mesitylene vapours. The response and recovery time of sensor 4 towards ethanol vapour at 20.4ppm were 82seconds and 74seconds, respectively. The limit of detection on ethanol vapour using sensor 4 was 789ppb. During detection, the ethanol vapour undergoes total deep oxidation on the surface of sensor 4.

NiFe2O4/g- C3N4 modified chitosan Schiff base composite for efficient removal of Cu(II) and Hg(II) ions from the aquatic environment and its antibacterial properties

Modification of chitosan has been achieved by the reaction of chitosan with 4- nitro-benzaldehyde via the sol-gel method, resulting in a Schiff base. A novel magnetic Graphitic Carbon Nitride/chitosan-Schiff base/NiFe2O3 (SBIV@NiFe/g-C3N4) adsorbent was synthesized by hydrothermal route for the adsorption of Cu(II) and Hg(II) ions from the aquatic environment. The synthesized SBIV@NiFe/g-C3N4 was characterized using infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and Brunauer-Emmett-Teller (BET), with a surface area of approximately 13.657 m2/g. It was anticipated by the results that magnetic SBIV@NiFe/g-C3N4 would be effectively synthesized. On Cu(II) and Hg(II) adsorption, the impacts of significant variables, including pH solution, contact duration, metal ion concentration, adsorbent dosage, and co-existing ions, were examined. Under ideal circumstances, the optimum adsorption capacities of Cu(II) and Hg(II) ions were 889.76 mg/g and 703.21 mg/g, respectively. Furthermore, the SBIV@NiFe/g-C3N4 material exhibited the beneficial property of simple separation, permitting the continuation of high removal effectiveness for heavy metals like Cu (II) and Hg(II) despite experiencing many reuse cycles. In summary, there are a lot of opportunities for the effective elimination of Cu (II) and Hg (II) from different water sources shortly with the use of SBIV@NiFe/g-C3N4, a new adsorbent. The as-synthesized SBIV@NiFe/g-C3N4 displayed better antibacterial activity against highly lethal bacteria like S. aureus and P. vulgaris.

Scalable fabrication of FeSnO3/gCN (FSO/gCN) nanohybrid: Effective electrocatalyst for oxygen evolution reaction in basic medium

The growing demand for renewable energy has prompted scientists to concentrate on developing robust electrocatalysts for enhanced water-splitting mechanisms. Water-splitting research requires electrocatalysts with superior electrochemical performance and an environmentally favorable character to create significant hydrogen energy resources. In this research, for first time, FSO based on graphitic carbon nitride (gCN) nanohybrid has been produced via an easy hydrothermal route. The developed electrocatalysts were characterized by several analytical analysis to analyze their morphology surface area and crystallinity. Meanwhile, FSO/gCN displayed excellent catalytic characteristics for OER in 1.0 M basic medium (KOH), which demonstrated reduced overpotential (207 mV) to attain 10 mA/cm2 and outstanding durability (20h). It also exhibited a small Tafel plot (37 mV/dec), small onset potential (1.26 V), a higher electrochemical active surface area (ECSA) of 561.5 cm2 and minimal charge transfer resistance (Rct) of 0.04 Ω, significantly superior to FSO material. Significantly, the FSO/gCN nanohybrid demonstrates long-term durability with 73.8 % retention of current density after 20 h. These results suggest that it has the potential to be employed to produce a very efficient and beneficial catalyst for OER, therefore paving the way for future opportunities.