Simple Solution Method Research Articles

Chemiresistive detection of xylene vapor using MOF-derived porous Co3O4 microrods activated by Mo6+ cations

Incorporation of high-valence cation into catalytic oxide (eg. Co3O4) is favorable for regulating the carrier concentration and creating more active centers for surface reaction process, thus promoting the sensing capability towards low reactive gas (eg. xylene). Herein, the metal-organic framework (MOF)-derived Mo-doped porous Co3O4 microrods are achieved through a simple solution method combing with a thermal method. The introduction of Mo6+ into Co3O4 matrix enhances the concentration of oxygen defects and Co3+, coupled with the specific surface area. As a result, the 5 at% Mo/Co3O4-based gas sensor sample exhibits a nice selectivity, clear response value (Rg/Ra=29.8 – 100 ppm), low concentration limit (0.5 ppm), and reliable stability to xylene vapor under a low working temperature (140 °C). Moreover, the possible reaction pathway (benzyl-benzaldehyde-benzoate-aromatic ester/anhydride) of xylene oxidation over this 5 at% Mo-doped Co3O4 microrod is proved by an in-situ DRIFTS analysis. Importantly, this optimized xylene-sensing capability is further discussed from the viewpoint of Mo-introducing effect into the porous Co3O4 microrods. This work further demonstrates a reliable approach of high valence cation-doped catalytic oxides to detect low reactive vapor.

Deep-Learning-Based Blood Glucose Detection Device Using Acetone Exhaled Breath Sensing Features of α-Fe2O3-MWCNT Nanocomposites.

Owing to the correlation between acetone in human's exhaled breath (EB) and blood glucose, the development of EB acetone gas-sensing devices is important for early diagnosis of diabetes diseases. In this article, a noninvasive blood glucose detection device through acetone sensing in EB, based on an α-Fe2O3-multiwalled carbon nanotube (MWCNT) nanocomposite, was successfully developed. Different amounts of α-Fe2O3 were added to the MWCNTs by a simple solution method. The optimized acetone gas sensor showed a response of 5.15 to 10 ppm acetone gas at 200 °C. Also, the fabricated sensor showed very good sensing properties even in an atmosphere with high relative humidity. Since the EB has high humidity, the proposed sensor is a promising device to exactly detect the amount of acetone in EB with high humidity. The sensor was powered by a 3200 mAh battery with the possibility of charging using mains electricity. To increase the reliability and calibration of the sensing device, a practical test was taken to detect acetone EB from 50 volunteers, and a deep learning algorithm (DLA) was used to detect the effect of various factors on the amount of acetone in each person's acetone EB. The proposed device with ±15 errors had almost 85% correct responses. Also, the proposed device had excellent response, short response time, good selectivity, and good repeatability, leading it to be a suitable candidate for noninvasive blood glucose sensing.

A Mild Synthesis of 0D Mn2+‐Doped Cs3CdBr5 Metal Halide for White Light‐Emitting Diodes and X‐Ray Imaging

AbstractAll‐inorganic Cd‐based metal halide is widely studied and applied in the field of optoelectronics due to its superior stability, diverse phase structure, and unique photoelectric properties. However, all‐inorganic 0D Cd‐based metal halide is not widely studied due to their extreme synthesis conditions. In this paper, a simple mild solution method is devised to successfully synthesize 0D Cs3CdBr5 by manipulating the crystal growth kinetics. Simultaneously, the influence of the doping element Mn on the transition matrix and the optical properties are investigated. By doping with an appropriate concentration of Mn2+, a green emission (520 nm) with photoluminescence quantum yield (PLQY) as high as 97.39% is obtained. Benefiting from near‐unity PLQY and the excellent optical properties, the white emitting light‐emitting diodes (WLEDs) with Cs3CdBr5:20%Mn as green phosphor exhibit warm white light emission with color rendering index (CRI) of 91 and correlated color temperature (CCT) of 4108 K. In addition, Cs3CdBr5:20%Mn also demonstrates excellent X‐ray scintillation properties with a low detection limit of 32.83 nGyair·s−1. The results show that Cs3CdBr5:Mn is not only a promising candidate for solid‐state lighting but also a promising candidate for low‐dose high‐resolution X‐ray imaging.

Three-phase power flow using binary tree search algorithm for unbalanced distribution networks

The main objective of this study is to examine a binary tree (BT) three-phase (3Φ) power flow analysis method for unbalanced distribution networks. A simple and efficient 3Φ power flow solution method for unbalanced radial distribution networks was proposed. This method is based on the BT search structure. Large-scale distribution network problems can be evaluated using current-injection techniques and two-port network models. The power flow solution process was simplified into a set of 3 × 3 matrix operations using the BT-based method. The solution complexity remained unchanged, regardless of the size of the power system. In other words, the performance and robustness of the proposed algorithm were maintained at relatively high values with increasing system size. Furthermore, programming complexity was reduced by standardising the solution process. The effectiveness and accuracy of the proposed model and algorithm were validated using four IEEE standard benchmark feeders and a series of random cases.

Enhancing Perovskite Solar Cell Performance through Propylamine Hydroiodide Passivation.

In recent years, the power conversion efficiency of perovskite solar cells has increased rapidly. Perovskites can be prepared using simple and cost-effective solution methods. However, the perovskite films obtained are usually polycrystalline and contain numerous defects. Passivation of these defects is crucial for enhancing the performance of solar cells. Here, we report the use of propylamine hydroiodide (PAI) for defect passivation. We found that PAI can result in higher-efficiency cells by reducing the defects and suppressing non-radiative recombination. Consequently, n-i-p perovskite solar cells with a certificated efficiency of 21% were obtained. In addition, PAI exhibited excellent performance in p-i-n devices by serving as a buried interface layer, leading to an improved efficiency of 23%.

(Invited) Enhanced Catalysis of Surface-Activated Metallic WSe2 Nanosheets By Single-Atom Pt for High-Performance Li-O2 Battery

Layered materials, such as TMDCs, exhibit various electronic structures attributed to their polymorphism and can be further modificated at the atomic level through chemical treatments. TMDCs in the metallic phase (1T or 1T’ phase) have gained attention as efficient electrocatalystic materials, due to their exceptional transport properties compared to TMDCs in the semiconducting phase (2H phase). TMDCs with the metallic phase have been prepared by atomic-scale post-treatments, such as an intercalation and single-atom doping. However, the precise role of these post-treatments in the catalytic performance of TMDCs is still ambiguous, as it is uncertain whether the enhanced properties arise from charge transfer kinetics in metallic phase or electrochemical properties induced by the post-treatment.Herein, we present a straightforward approach fabrication for fabricating metallic WSe2 nanosheets, which serve as an excellent support for single-atom Pt doping. The incorporation of single-atom Pt into WSe2 nanosheets was achieved using a simple solution method at room temperature. Extensive measurements were conducted, including XAS, XPS, and XPDF to investigate the local coordination structure of Pt-WSe2. These measurements confirmed the presentce of single-atom Pt doping within WSe2 layers. The introduction of single-atom Pt significantly enhanced the kinetics of the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), leading to improved performance of Li-O2 batteries. Experimental measurements and DFT calculations provided evidence that the enhanced catalytic abilities of Pt-WSe2 originated from the improved interaction between oxygen and the Se vacancy on basal planes of WSe2. Consequently, the Li-O2 battery incorporating the Pt-WSe2 catalyst exhibited a stable discharge and charge cycle for up to 350 cycles, demonstrating its superior durability.

An Accurate Calculation Method on Blasingame Production Decline Model of Horizontal Well with Dumbbell-like Hydraulic Fracture in Tight Gas Reservoirs

Blasingame production decline is an effective method to obtain permeability and single-well controlled reserves. The accurate Blasingame production decline curve needs an accurate wellbore pressure approximate solution of the real-time domain. Therefore, the aim of this study is to present a simple and accurate wellbore pressure approximate solution and Blasingame production decline curves calculation method of a multi-stage fractured horizontal well (MFHW) with complex fractures. A semi-analytical model of MFHWs in circle-closed reservoirs is presented. The wellbore pressure and dimensionless pseudo-steady productivity index JDpss (1/bDpss) are verified with a numerical solution. The comparison result reaches a good match. Wellbore pressure and Blasingame production decline curves are used to analyze parameter sensitivity. Results show that when the crossflow from matrix to natural fracture appears after the pseudo-state flow regime, the value of the inter-porosity coefficient has an obvious influence on the pressure approximate solution of the pseudo-steady flow regime in naturally fractured gas reservoirs. The effects of relevant parameters on wellbore pressure and the Blasingame decline curve are also analyzed. The method of pseudo-steady productivity index JDpss can applied to all well and reservoir models.

An electrocatalytic sensing of 2, 6-dichlorophenol based on Dy2O3-Co3O4@CeO2 nanocomposite modified GCE: An enhanced environmental safety

Anthropogenic activities are continuously polluted our environment by releasing various kind of toxic chemicals as waste product. Their removal has gained the impressive importance among the scientists in order to maintain the integrity of our ecosystem. In this present work, Dy2O3-Co3O4@CeO2 nanocomposite (NC) was prepared by simple solution method with the aspiration to detect as well as electro-hydrolyzed the toxic chemicals in an aqueous system. Structural, morphological and optical properties of our newly synthesised nanocomposite were investigated by using advanced analytical tools such as ultraviolet–visible difused reflectance spectroscopy (UV-DRS), fourier transform infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD), field emission scanning electron microscope equipped with energy dispersive spectroscopy (FESEM-EDS), and transmission electron microscope (TEM) in addition to Brunauer-Emmet-Teller (BET) analysis. After detailed characterization of newly synthesized Dy2O3-Co3O4@Ce2O3 nanocomposite, it was used with 5 % PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrenesulfonate), a conducting polymer binder, to modify the glassy carbon electrode (GCE) as selective electrochemical sensor (Dy2O3-Co3O4@CeO2-NC/PEDOT:PSS/GCE). After that, this newly designed Dy2O3-Co3O4@CeO2-NC/PEDOT:PSS/GCE was evaluated so as to check its detection as well as electrocatalytic behaviour against the toxic chemicals in an aqueous system using novel electrochemical current–potential (I–V) approach, for the first time. A comparative investigation revealed that this newly designed Dy2O3-Co3O4@CeO2-NC/PEDOT:PSS/GCE was very selective against the 2, 6-dichlorophenol (2, 6-DCP) and had good affinity with it even in the company of other interference chemicals. In order to optimise newly developed Dy2O3-Co3O4@CeO2-NC/PEDOT:PSS/GCE as an effective as well as selective 2, 6-DCP electrochemical sensor, analytical parameters such as, limit of detection (LOD), limit of quantification (LOQ), sensitivity etc were calculated from slop of calibration curve. The LOD at signal-to-noise ratio (S/N) of 3, LOQ, and sensitivity were calculated as 0.014 ± 0.001 nM, 0.046 ± 0.001 nM, and 65.82 µAµM-1cm−2, respectively, over a linear dynamic range (LDR) of our target analyte concentration (0.1 nM – 0.1 M) with r2 square value as 0.9988. Consequently, this study enlightens us that this newly fabricated electrochemical sensor, selective only for 2, 6-DCP, is very cost-effective, efficient, and stable over time. Moreover, it also initiates a new way to effectively interrogate the various toxic chemicals in real samples by using a novel electrochemical (I–V) approach based on reported / non-reported different kind of semiconductor nanocomposite modified GCEs as selective electrochemical sensors.

Influence of graphitic phase on the structural, optical, electrical and photocatalytic properties of BiFeO3/KNbO3 based binary nanocomposites

Synthesis of ternary nanocomposites of BiFeO3-Graphene-KNbO3 through simple solution method has been made at various concentrations of graphene ranging 0.025–0.1 % mole fraction. The obtained nanocomposite powders with varying content of graphitic phase were subjected to different characterization techniques such as XRD, Raman, SEM/EDX/Elemental mapping, HR-TEM, UV–Vis–NIR spectroscopy, dielectric and photodegradation measurements. All above studies have provided the collective impression of the existence of all entities in the prepared ternary composites. Dielectric studies revealed that progressive loading of graphene content led to the increased pathway for the conduction of electrons in the sample. However, the loading of graphene at appropriate concentration has brought out increased dye degradation capacity of BiFeO3-Graphene-KNbO3 ternary nanocomposites towards methylene blue dye. The results obtained from various studies have been discussed in detail.

Biophysical phenotyping of single-cell based on impedance and application for individualized precision medicine

Single-cell biophysical characterization based on impedance measurement is an advantageous approach due to its label-free, high-efficiency, cost-effective and real-time capability. Biophysical phenotyping can yield timely and rich information on physiological and pathological state of cells for disease diagnosis, drug screening, precision medicine, etc. However, precise measurement on single-cell impedance is challenging, particularly hard to figure out the detailed biophysical parameters of single cell due to coupling and complexity of impedance model. Here, we propose an analytic determination method to decode single-cell electrophysiological parameters (including cell-substrate interface capacitance, cell membrane capacitance, cell membrane conductivity, and cytoplasm conductivity) from the impedances measured at optimized frequencies by using analytic solution rather than spectrum fitting. With this simple and fast analytic solution method, the physiological parameters of single cell in natural adhesion state can be accurately determined in real time. We validate this cell parameter determination method in monitoring the change of cell adhesion under hydraulic effects and exploring electrophysiological differences among MCF-7, HeLa, Huh7, and MDA-MB-231 cell lines. Particularly, we apply the approach to optimize tumor treating fields (TTFields) therapy, realizing individualized precision medicine. Our work provides an accurate and efficient approach for characterizing single-cell biophysical properties with real-time, in-situ, label-free, and less invasive advantages.

Application of modified kaolinite in improving thermal stability of polydimethylsiloxane

AbstractThis research investigated the chemical structure and morphology of the hydrogenated tallow amine (HTA)‐intercalated kaolinite by XRD, FT‐IR, and TEM measurements. The experimental outcomes show that intercalation of kaolinite by HTA, with an intercalation rate of 63.2%, expands the interlayer distance with a subsequent dominant basal XRD peak at 2θ ≈ 7.9°. Furthermore, a composite was created from the HTA‐intercalated kaolinite and polydimethylsiloxane (PDMS) through a favorable interaction between the end silanol groups of PDMS and the modified kaolinite surface. Thermogravimetry‐differential scanning calorimetry results indicate that introducing the HTA‐intercalated kaolinite into the PDMS matrix increases the thermal stability of the composite from 178 to 343 °C. However, the thermal stability of the composite is lower than that of other published materials. The synthesis of kaolinite/PDMS composite with enhanced structural and thermal stability outcomes has been provided via a simple and effective solution method that should have further applications.

Enhanced electrochemical properties of PbO-rGO nanocomposite prepared by wet chemical method for supercapacitor applications

The supercapacitor is a future energy device because of its higher power density and outstanding cyclic stability with a quick charge and discharge process. Supercapacitors have a lower energy density than regular batteries. The electrochemical characteristic of supercapacitors is strongly depend on the electrode materials. The nanostructured electrode materials continue to be a main focus of supercapacitor research. The considered electrode materials, such as, Lead oxide (PbO) and reduced graphene oxide (rGO) have been widely used in supercapacitors due to their fascinating physicochemical properties. The PbrG was synthesized using the simple and cost-effective ultrasonic-assisted solution method. The prepared PbO and PbrG were examined in XRD, TEM and XPS. The XRD studies confirmed the presence of crystal structure in PbO and PbrG. The TEM images reveal the embellishment of PbO on the rGO sheets. The PbrG showed a higher specific capacitance (448 F/g) compared to PbO NANO (177 F/g) with better cycling stability until 5000 cycles and exhibited excellent conductivity due to the presence of rGO. These properties of PbrG ensures that this electrode material play a beneficial role in the energy storage applications.

Optical and UV Shielding Properties of Inorganic Nanoparticles Embedded in Polymethyl Methacrylate Nanocomposite Freestanding Films.

Polymethyl methacrylate (PMMA) is an interesting polymer employed in various applications due to its outstanding properties. However, its electrical and mechanical properties can be further improved by incorporating nanoparticles, and in particular, PMMA nanocomposite with nanoparticles provides various multifunctional properties. This work reports PMMA nanocomposite preparation and structural and optical characterizations incorporating carbon nanotubes (CNTs), TiO2 nanoparticles, and carbon quantum dots (CQDs). CNT/PMMA, TiO2/PMMA, and CQD/PMMA nanocomposite freestanding films were prepared using a simple solution method. Various properties of the prepared composite films were analyzed using scanning electron microscopy, X-ray diffraction, photoluminescence, Fourier transform infrared, and UV-Vis and Raman spectroscopy. Optical parameters and photocatalytic dye degradation for the films are reported, focusing on the properties of the materials. The CNT/PMMA, TiO2/PMMA, and CQD/PMMA films achieved, respectively, good electrical conductivity, photodegradation, and fluorescence compared with other composite films.

A Multifunctional Nanozyme Integrating Antioxidant, Antimicrobial and Pro-Vascularity for Skin Wound Management.

Skin wounds are a prevalent issue that can have severe health consequences if not treated correctly. Nanozymes offer a promising therapeutic approach for the treatment of skin wounds, owing to their advantages in regulating redox homeostasis to reduce oxidative damage and kill bacteria. These properties make them an effective treatment option for skin wounds. However, most of current nanozymes lack the capability to simultaneously address inflammation, oxidative stress, and bacterial infection during the wound healing process. There is still great potential for nanozymes to increase their therapeutic functional diversity and efficacy. Herein, copper-doped hollow mesopores cerium oxide (Cu-HMCe) nanozymes with multifunctional of antioxidant, antimicrobial and pro-vascularity is successfully prepared. Cu-HMCe can be efficiently prepared through a simple and rapid solution method and displays sound physiological stability. The biocompatibility, pro-angiogenic, antimicrobial, and antioxidant properties of Cu-HMCe were assessed. Moreover, a full-thickness skin defect infection model was utilized to investigate the wound healing capacity, as well as anti-inflammatory and pro-angiogenic properties of nanozymes in vivo. Both in vitro and in vivo experiments have substantiated Cu-HMCe's remarkable biocompatibility. Moreover, Cu-HMCe possesses potent antioxidant enzyme-like catalytic activity, effectively clearing DPPH radicals (with a scavenging rate of 80%), hydroxyl radicals, and reactive oxygen species. Additionally, Cu-HMCe exhibits excellent antimicrobial and pro-angiogenic properties, with over 70% inhibition of both E. coli and S. aureus. These properties collectively promote wound healing, and the wound treated with Cu-HMCe achieved a closure rate of over 90% on the 14th day. The results indicate that multifunctional Cu-HMCe with antioxidant, antimicrobial, and pro-angiogenic properties was successfully prepared and exhibited remarkable efficacy in promoting wound healing. This nanozymes providing a promising strategy for skin repair.

AX·(H2SeO3)n (A = K, Cs; X = Cl, Br; n = 1, 2): A Series of Ionic Cocrystals as Promising UV Birefringent Materials with Large Birefringence and Wide Band Gap.

The design and syntheses of new birefringent crystals will be of great importance in commercial applications and materials science. A series of ultraviolet (UV) birefringent crystals, AX·(H2SeO3)n (A = K, Cs; X = Cl, Br; n = 1, 2), with large sizes up to 23 × 6 × 3 mm3, was successfully synthesized by simple aqueous solution method. These four compounds belong to three different space groups. Isomorphic KCl·(H2SeO3)2 and CsCl·(H2SeO3)2 crystallize in the space group, while CsBr·(H2SeO3)2 and CsCl·H2SeO3 crystallize in the P21/m and P21/c space groups, respectively. They exhibit cocrystal structures composed of [2(H2SeO3)]∞ and [AX]∞ frameworks, ingeniously inheriting the large optical anisotropy of selenite and the wide band gap of alkali metal halide. And it proves that these compounds indeed possess large birefringence (0.1-0.17 at 532 nm) and short UV cutoff edges (227-239 nm), achieving a balance of optical properties. This research affords a simple and viable strategy for the design and syntheses of new UV birefringent crystals. Besides, it is also found that the n value and ionic size (A and X ions) have important influences on the crystal structures and optical properties of AX·(H2SeO3)n. And this will promote further understanding of the alkali metal halide selenite family.

Potassium doping for grain boundary passivation and defect suppression enables highly-efficient kesterite solar cells

The complicated and diverse deep defects, voids, and grain boundary in the CZTSSe absorber are the main reasons for carrier recombination and efficiency degradation. The further improvement of the open-circuit voltage and fill factor so as to increase the efficiency of CZTSSe device is urgent. In this work, we obtained K-doped CZTSSe absorber by a simple solution method. The medium-sized K atoms, which combine the advantages of light and heavy alkali metals, are able to enter the grain interior as well as segregate at grain boundary. The K-Se liquid phase can improve the absorber crystallinity. We find that the accumulation of the wide bandgap compound K2Sn2S5 at grain boundary can increase the contact potential difference of grain boundary, form more effective hole barriers, and enhance the charge separation ability. At the same time, K doping passivates the interface as well as bulk defects and suppresses the non-radiative recombination. The improved crystallinity, enhanced charge transport capability and reduced defect density due to K doping result in a significant enhancement of the carrier lifetime, leading to 13.04 % device efficiency. This study provides a new idea for simultaneous realization of grain boundary passivation and defect suppression in inorganic kesterite solar cells.

Regulating the frontier orbital of iron phthalocyanine with nitrogen doped carbon nanosheets for improving oxygen reduction activity.

Iron phthalocyanine (FePc) has attracted widespread attention for its tunable electronic structure. However, the Fe-N sites suffer from undesirable oxygen reduction activity due to the symmetric geometries. A suitable substrate was thus needed to induce electron redistribution around Fe-N to improve the activity. Herein, ultrathin nitrogen-doped carbon nanosheets (N-CNSs) were prepared by a simple high temperature pyrolysis. Then iron phthalocyanine was loaded on the ultrathin nitrogen-doped carbon nanosheets (FePc@N-CNSs) by a low-cost and simple solution method. This composite catalyst shows an excellent ORR activity with a half potential of 0.88 V, an onset potential of 0.99 V and durability superior to commercial Pt/C. When used as an air cathode catalyst for rechargeable zinc-air batteries, FePc@N-CNS modified batteries outperform Pt/C + RuO2 modified batteries with higher power density and superior constant current charge-discharge cycling stability of 37 hours. The regulated electronic structure of FePc by the N-CNS substrate was revealed further by DFT calculations, which explained the enhanced adsorption of the active center to the intermediates and the increased ORR performance.

Pickering high internal phase emulsions stabilized by metal-organic framework nanoribbons

Pickering high internal phase emulsions (HIPEs) stabilized by colloidal particles are of great practical significance in the formulation of food, pharmaceutical, cosmetic, paint products and the chemical oil flooding. Herein, we report that a manganese-based metal–organic framework (MOF) (Mn3(BTC)2 (BTC = 1,3,5-benzenetricarboxylate)) nanoribbons synthesized by a simple solution method can stabilize water-in-oil (W/O) high-viscosity Pickering HIPEs with crude oil as oil phase for more than one month at 43 °C. The Mn3(BTC)2 nanoribbons assemble at the oil/water interface of HIPE, owing to its advantageous structural features with the size of several micrometers, thickness of about 100 nm and amphiphilicity originated from the hydrophilic metal ions and hydrophobic organic ligands. The phase behavior and properties of the as-prepared HIPEs strongly depend on the MOF concentration (CMOF) and internal phase volume fraction of water (Fw) of emulsion. The MOF dispersions and crude oil are miscible into stable W/O HIPEs at Fw = 75 % when the CMOF ranges from 50 ppm to 5000 ppm. More interestingly, the viscosity of W/O emulsions greatly increases as the Fw varying from 50 % to 80 % and a viscosity of 4.5 Pa·s is obtained at CMOF = 2000 ppm and Fw = 80 %, which is nearly 400 times higher than that of crude oil. Moreover, the pressure generated by HIPEs flowing in core is about 40 times more than that of water injection and can remain the highest stable value substantially. These results show that the MOF dispersions are favorable to form stable W/O emulsions with high internal phase volume fraction, which has a great potential in improving oil displacement efficiency of chemical flooding.

Fabrication of solid polymer electrolyte based on carboxymethyl cellulose complexed with lithium acetate salt as Lithium‐ion battery separator

AbstractPolymer electrolyte is a crucial component of solid‐state‐lithium‐ion batteries that role both as separators and electrolytes. The host polymer and lithium salt selection are crucial for producing a solid polymer electrolyte with optimum characteristics. This research aims to study the effect of lithium acetate (LiCH3COO) salt on carboxymethyl cellulose (CMC)‐based solid polymer electrolytes. The LiCH3COO‐complexed CMC solid polymer electrolyte was prepared using the solution casting method with various weight percentages of LiCH3COO, that is, 0%wt, 10%wt, 20%wt, and 30%wt. The ionic conductivity analysis was conducted by using electrochemical impedance spectroscopy (EIS), infrared analysis by Fourier transform infra‐red (FTIR), mechanical analysis, crystallinity degree analysis with X‐ray diffraction (XRD), and thermogravimetry analysis (TGA), differential thermogravimetry (DTG), and differential scanning calorimetry (DSC). The interaction between Li+ ions and CMC enhanced ionic conductivity, decreased mechanical strength, reduced crystallinity degree, and lowered thermal properties. The CMC/LiCH3COO (70/30) SPE was selected as the optimum condition because it exhibited good ionic conductivity and sufficient thermal stability, while it needs a mechanical strength improvement. Molecular dynamics simulations were also performed at the density‐functional tight‐binding (DFTB) level to unravel the molecular mechanism of the Li‐ion hopping in CMC. The CMC/LiCH3COO (70/30) showed the highest electrochemical window as high as 3.5 V. Based on the results, CMC complexed with 30 (%wt) LiCH3COO salt showed high potential as a polymer electrolyte for lithium‐ion battery applications.Highlights Fabrication of solid polymer electrolyte based on carboxymethyl cellulose complexed with lithium acetate salt was conducted by simple casting solution method. The 30%wt LiCH3COO into carboxymethyl cellulose (CMC)‐polymer host showed the highest ionic conductivity of 2.47 × 10−5 S cm−1. The 30%wt LiCH3COO‐complexed CMC shows some degradation peaks, they are water evaporation, decomplexation, depolymerization, melting, and completely degraded. The density‐functional tight‐binding method suggests that the Li‐ions hop both in perpendicular and parallel directions of the cellulose layers. The CMC/LiCH3COO (70/30) showed the highest electrochemical window as high as 3.5 V.

Antibacterial and Photocatalytic Activity of ZnO/Au and ZnO/Ag Nanocomposites

The use of a combination of nanoparticles as antimicrobial agents can be one strategy to overcome the tendency of microbes to become resistant to antibiotic action. Also, the optimization of nano-photocatalysts to efficiently remove persistent pollutants from wastewater is a hot topic. In this study, two composites ZnO/Au (1% wt.) and ZnO/Ag (1% wt.) were synthesized by simple aqueous solution methods. The structure and morphology of the r nanocomposites were analyzed by structural and optical characterization methods. The formation of AuNPs and AgNPs in these experiments was also discussed. The antimicrobial properties of ZnO, ZnO/Au, and ZnO/Ag nanomaterials were investigated against Gram-negative bacteria (Pseudomonas aeruginosa) and Gram-positive bacteria (Staphylococcus aureus). The results showed an increase of 80% in the antimicrobial activity of ZnO/Au against Pseudomonas aeruginosa compared with 30% in the case of ZnO/Ag. Similarly, in the case of the S. aureus strain tests, ZnO/Au increased the antimicrobial activity by 55% and ZnO/Ag by 33%. The photocatalytic tests indicated an improvement in the photocatalytic degradation of methylene blue (MB) under UV irradiation using ZnO/Au and ZnO/Ag nanocomposites compared to bare ZnO. The photocatalytic degradation efficiency of ZnO after 60 min of UV irradiation was ∼83%, while the addition of AuNPs enhanced the degradation rate to ∼95% (ZP2), and AgNP presence enhanced the efficiency to ∼98%. The introduction of noble metallic nanoparticles into the ZnO matrix proved to be an effective strategy to increase their antimicrobial activity against P. aeruginosa and S. aureus, and their photocatalytic activity was evaluated through the degradation of MB dye. Comparing the enhancing effects of Au and Ag, it was found that ZnO/Au was a better antimicrobial agent while ZnO/Ag was a more effective photocatalyst under UV irradiation.