Search

Titanium dioxide (TiO2) nanoparticles have gained significant attention due to their wide-ranging applications. This research explores an approach to functionalize Niobium Nitrogen Titanium Dioxide nanoparticles (Nb-N-TiO2 NPs) with Mentha arvensis ethanolic leaf extracts. This functionalization allows doped NPs to interact with the bioactive compounds in extracts, synergizing their antioxidant activity. While previous studies have investigated the antioxidant properties of TiO2 NPs synthesized using ethanolic extracts of Mentha arvensis, limited research has focused on evaluating the antioxidant potential of doped nanoparticles functionalized with plant extracts. The characterization analyses are employed by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Ultraviolet–visible (UV–Vis) spectroscopy to evaluate these functionalized doped nanoparticles thoroughly. Subsequently, the antioxidant capabilities through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) assays have been assessed. Within functionalized Nb-N-TiO2, the FTIR has a distinctive peak at 2350, 2010, 1312, 1212, and 1010 cm−1 with decreased transmittance associated with vibrations linked to the Nb-N bond. SEM revealed a triangular aggregation pattern, 500 nm to 2 µm of functionalized Nb-N-TiO2 NPs. Functionalized doped Nb-N-TiO2 NPs at 500 µg mL−1 exhibited particularly robust antioxidant activity, achieving an impressive 79% efficacy at DPPH assessment; meanwhile, ferric reduction efficiency of functionalized doped Nb-N-TiO2 showed maximum 72.16%. In conclusion, doped Nb-N-TiO2 NPs exhibit significantly enhanced antioxidant properties when functionalized with Mentha arvensis ethanolic extract compared to pure Nb-N-TiO2 manifested that doped Nb-N-TiO2 have broad promising endeavors for various biomedicine applications. [ABSTRACT FROM AUTHOR]

Titanium dioxide nanoparticles (TiO2 NPs) have garnered considerable attention due to their diverse applications. Introducing niobium (Nb) and nitrogen (N) doping, followed by functionalization with Mucuna pruriens beans methanolic extracts, offers a novel avenue to harness their antioxidant potential. This functionalization enables Nb-N doped TiO2 NPs to engage with the bioactive compounds inherent to M. pruriens beans methanolic extracts, thereby fostering a synergistic enhancement of antioxidant activity. This study focuses on the functionalization of doped Nb-N-TiO2 NPs and evaluates the antioxidative capabilities of those functionalized NPs to pure doped Nb-N-TiO2 NPs. These functionalized NPs (FNb-N-TiO2) underwent characterization through ultraviolet–visible spectroscopy (UV–Vis), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning electron microscopy (SEM) analysis. Subsequently, their antioxidant capabilities were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric Reducing Antioxidant Power Assay (FRAP) assays. Functionalized Nb-N-TiO2 NPs FTIR peaks exhibited at 2430 and 2010 cm−1; unrelated peak vibrations are associated with the (Nb-N) doping, and the increased transmittance signifies successful functionalization and potential bonding between M. pruriens extract phytochemicals. A distinctive triangular aggregation pattern in SEM ranging in size from 5 µm to 500 nm was seen in FNb-N-TiO2. At a concentration of 500 μL−1, FNb-N-TiO2 exhibited exceptionally high antioxidant activity, reaching an impressive 70% compared with pure Nb-N-TiO2 NPs at 51%. The results demonstrated that FNb-N-TiO2 NPs exhibit significant antioxidant properties compared to their non-functionalized, pure Nb-N-TiO2 NPs. In conclusion, this study substantiates the considerable antioxidant potential of doped Nb-N-TiO2 NPs mediated by M. pruriens methanolic extract, thereby emphasizing their potential for diverse applications in both biomedical and environmental sciences. [ABSTRACT FROM AUTHOR]

To solve the problem of water pollution, using environment friendly and cost effective method in short time is the need of hour. In this work, chromium (Cr) and nitrogen (N) co-doped TiO2 nanoparticles were synthesized and were used for the photocatalytic degradation of dyes under visible light. The synergistic effect of metal and non-metal co-dopants added would result in appropriate reduction of band gap {from 3.2 eV of TiO2 to 2.67 eV}, decrease in recombination rate of charge carriers by trapping electrons and holes, and in better light harvesting capacity. Nanoparticles were synthesized by sol–gel method and characterized using ultraviolet–visible (UV–VIS) spectroscopy, fourier transform infrared (FTIR) spectroscopy, atomic force microscopy (AFM), zeta potential, X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analysis, field emission scanning electron microscopy (FE-SEM), and RAMAN spectroscopy. Eosin yellow (EY) and rose bengal (RB) were subjected to photocatalytic degradation under solar light to check the photocatalytic activity of the synthesized nanoparticles. Effects of dye concentration, the concentration of nanoparticles, time, and pH were investigated to optimize the parameters. The results obtained were remarkable for 20 ppm EY solution took 10 min using 1 gL−1 NPs at pH 3 and 10 ppm RB solution took 5 min using 0.75 gL−1 NPs at pH 5.78 (original pH) for complete degradation. Kinetics studies were also performed and both dyes followed pseudo-second-order kinetics with R2 values 0.99312 and 0.99712 for EY and RB, respectively. The study of degraded products was conducted using high-performance liquid chromatography (HPLC) hyphenated with electron spray ionization mass spectroscopy (ESI–MS) (LC–MS) and possible degradation pathways were made for both dyes. A reusability test was also performed showing the efficiency of the particles was up to 88% after 3 cycles of use. These notable results can be attributed to the efficient removal of organic pollutants using the proposed dopants in this study. [ABSTRACT FROM AUTHOR]

BACKGROUND: Organic dyes are extremely hazardous waste toxins because they can harm all living organisms as well as the environment. Among them, azo dyes are the most harmful, containing a non‐degradable azo group (NN); these dyes are highly hazardous for both humans and animals, even in low concentration. This research study aims to remove hazardous anionic azo dyes from aqueous solutions by a simple adsorption method using zinc oxide quantum dots (ZnO QDs) synthesized by a facile precipitation method. RESULTS: As synthesized, ZnO QDs were characterized by transmittance electron microscopy, atomic force microscopy, X‐ray powder diffraction, Fourier transform infrared spectroscopy, zeta potential and Brunauer–Emmett–Teller. The azo dyes Methyl Orange (MO), Congo Red (CR) and Eriochrome Black‐T (EBT) have been removed actively from an aqueous solution using the high adsorption characteristic of ZnO QDs. The results demonstrated that the adsorbent was efficient even at a low concentration at 0.05 g L−1. The maximum adsorption capacity of ZnO QDs at 27 ± 1 °C was 102.9, 124.3 and 60 mg L−1 for MO, CR and EBT, respectively, and all these results have been observed in just 30 min. A pseudo‐second‐order and Langmuir isotherm model satisfactorily suited the dye adsorption data and, up to three cycles, the ZnO QDs demonstrated outstanding reusability. CONCLUSION: ZnO QDs showed not only efficient removal of individual dyes but also simultaneous removal of azo dyes from mixture solution and proved to be an effective, eco‐friendly, low‐cost adsorbent for dye decontamination in wastewater. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The purpose to conduct this research work is to study the effect of photocatalytic degradation by developing cost-effective and eco-friendly nitrogen and tungsten (metal/non-metal) co-doped titania (TiO2). The inherent characteristics of synthesized nanoparticles (NPs) were analyzed by Fourier transform infra-red spectroscopy (FT-IR), ultra-violet visible (UV-Vis) spectroscopy, Raman spectroscopy, Field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS), X-ray diffraction (XRD) spectrometry, and atomic force microscopy (AFM). Co-doping of metal and non-metal has intensified the photocatalysis trait of TiO2 nanoparticles in an aqueous medium. This co-doping of transition metal ions and modification of nitrogen extended the absorption into the visible region subsequently restraining the recombination of electrons/holes pair. The stronger light absorption in the visible region was required for the higher activity of photodegradation of dye under visible light illumination to confine bandgap energy which results in accelerating the rate of photodegradation. After efficient doping, the bandgap of titania reduced to 2.38 eV and caused the photodegradation of malachite green in visible light. The results of photocatalytic degradation were confirmed by using UV/Vis. spectroscopy and high-performance liquid chromatography coupled with a mass spectrophotometer (HPLC-ESI-MS) was used for the analysis of intermediates formed during photocatalytic utility of the work. [ABSTRACT FROM AUTHOR]

The charge trapping characteristics of an organic nanocomposite based on two polymers, poly(3-hexylthiophene-2,5-diyl) (P3HT) and orange dye (OD), were investigated by fabricating a sandwiched structure on a flexible polyethylene terephthalate substrate. The fabricated flexible organic device with a configuration of silver (Ag)/P3HT–OD/Ag displayed highly stable results consistent with a bipolar non-volatile resistive random access memory (RRAM) device using simple and controllable fabrication technology. It was observed that by the addition of OD, low threshold voltages (Vth) of Vset = 1.5 V and Vreset = −1.5 V were achieved owing to the values of work function and energy bandgap of the materials used. Electrical rewritable effects of the fabricated memory device were tested for 102 voltage sweeps and 104s without any considerable degradation of its bistable resistive states. The switching mechanism was considered to be space charge limited current and this was verified by plotting the double logarithmic I–V curve. This is the first RRAM device based on P3HT polymer whose mechanical robustness has been tested for its mechanical robustness by bending it for 25 bending cycles at a bending diameter ranging from 15 cm to 5 cm without any considerable change in its properties. This finding offers important guidelines for reproducing next-generation flexible organic nanocomposite-based memory devices that are simple to fabricate and have low operating voltages and highly stable memory behavior. [ABSTRACT FROM AUTHOR]

Soft robots have received an increasing attention due to their advantages of high flexibility and safety for human operators but the fabrication is a challenge. Recently, 3D printing has been used as a key technology to fabricate soft robots because of high quality and printing multiple materials at the same time. Functional soft materials are particularly well suited for soft robotics due to a wide range of stimulants and sensitive demonstration of large deformations, high motion complexities and varied multi-functionalities. This review comprises a detailed survey of 3D printing in soft robotics. The development of key 3D printing technologies and new materials along with composites for soft robotic applications is investigated. A brief summary of 3D-printed soft devices suitable for medical to industrial applications is also included. The growing research on both 3D printing and soft robotics needs a summary of the major reported studies and the authors believe that this review article serves the purpose. [ABSTRACT FROM AUTHOR]

In this work, a polymeric material poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and a two dimensional material molybdenum disulfide (MoS 2 ) 2D nanoflakes have been employed as the active layers of two separate transducers on a single substrate for the detection of relative humidity. The portion with MoS 2 based active region showed high responsivity towards low humidity levels while PEDOT:PSS based portion responded well to high humidity levels. These two sensing portions were connected in a series combination to fabricate a single humidity sensing device capable to respond to a wide range of relative humidity with very high sensitivity. 2D MoS 2 nanoflakes were obtained by aqueous exfoliation of pristine MoS 2 . The transducer electrode pairs were fabricated using reverse offset printing technique on a piezoelectric LiNbO 3 substrate. The active thin film of MoS 2 flakes was deposited by Electrohydrodynamic atomization (EHDA) while the thin film of PEDOT:PSS was deposited by SAW-EHDA hybrid system. The fabricated sensor is capable of sensing relative humidity with high sensitivity (50 kΩ/%RH or 800 Hz/%RH) in a wide range of 0%RH–80%RH. The response and recovery times are also excellent with values of 0.5 s and 0.8 s respectively. This unique approach of combining multiple transducers in a single sensing device can lead to the development of high performance sensors and can solve the current limitations of single transducer based sensing devices. [ABSTRACT FROM AUTHOR]

Polyethylene oxide (PEO) is a polymer hydrogel possessing ionic conductivity that varies with different percentage of absorbed water molecules and ions. This property makes it a good candidate to be used in humidity sensors’ active layers. The degree of crystallinity of PEO thin films decrease with increasing humidity that facilitates the ion conduction in the thin films, thus reducing the film impedance. In this research work, the humidity sensing properties of the thin films of semi-crystalline PEO have been investigated and the material is then modified to its amorphous dominant phase by heating the thin films beyond the melting point of the polymer. The slowly cooled resulting thin films had a waxy solid like appearance and showed an excellent response towards quantitative detection of relative humidity in the surrounding environment. The results show a roughly linear impedance versus relative humidity curve in the range of 0% RH to 90% RH with a very high maximum achieved sensitivity of ∼35 kΩ/%RH. The response and recovery times measured for the modified sensors were 2.8 s and 5.7 s respectively. The 30 day trial of stability readings showed a standard deviation of only 1%. The results prove thermally modified amorphous PEO thin films to be strong candidates for high end electronic relative humidity sensors. [ABSTRACT FROM AUTHOR]

The resistive switching effect of various materials has been investigated because of their promising advantages such as high scalability, low cost, simple structure and less power consumption of such memory devices. In this study, the resistive switching effect in nanocomposites of zinc oxide nanowires (ZnO NWs) and zinc stannate nanocubes (ZnSnO3 NCs) has been explored. The device was fabricated on a flexible poly(ethylene terephthalate) substrate on which highly conductive (0.3 Ω cm) patterns of silver (Ag) were deposited as bottom electrodes using a reverse offset printing technique. Vertically aligned and highly dense ZnO NWs were grown on the Ag patterns using hydrothermal synthesis followed by spraying of ZnSnO3 NCs using an electrohydrodynamic atomization (EHDA) technique. Finally, the top Ag electrode was patterned using an EHD patterning technique to complete the fabrication of the device. The fabricated device exhibited bipolar and rewritable characteristics, and had a nonvolatile resistive switching memory with an off/on ratio of 5.8 × 102 and a retention time of 104 s at a small operating voltage (1.2 V). The electrical results obtained with the Ag–ZnO/ZnSnO3–Ag memory device were remarkable and they showed significant repeatability. The significantly stable, highly durable and promising results obtained with the ZnO NWs–ZnSnO3 NCs heterostructure make this semiconductive nanocomposite a potential candidate for use in future flexible memory devices. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid nanocomposites are an attractive choice for various electronic device applications. Owing to the unique characteristics of hybrid nanocomposites, we have explored the memory effect in a device, based on a 2D material: boron nitride (BN) and a polymer, polyvinyl alcohol (PVOH). This memory device has been fabricated on a flexible ITO coated PET substrate by using an all printed approach including electrohydrodynamic atomization (EHDA) and reciprocating head (RPC). The fabricated device displayed nonvolatile, rewritable and characteristic bipolar resistive switching at a low current compliance and small operating voltage. The conduction mechanism was deduced to be conductive filamentary and verified by the effect of temperature and device size on switching characteristics. Raman, FTIR and UV/Vis spectroscopies were employed in studying the optical properties of as-deposited hBN/PVOH thin films. The morphological characteristics were analyzed by FESEM and AFM techniques. A bendability test at various bending diameters (50–4 mm) for 1500 cycles was carried out to show the mechanical robustness of the fabricated device. The remarkably stable and repeatable results of electrical and mechanical characterization make this hybrid nanocomposite a potential candidate for future flexible, robust and low power nonvolatile memory devices. [ABSTRACT FROM AUTHOR]

Owing to the increasing interest in the nonvolatile memory devices, resistive switching based on hybrid nanocomposite of a 2D material, molybdenum disulphide (MoS2) and polyvinyl alcohol (PVA) is explored in this work. As a proof of concept, we have demonstrated the fabrication of a memory device with the configuration of PET/Ag/MoS2-PVA/Ag via an all printed, hybrid, and state of the art fabrication approach. Bottom Ag electrodes, active layer of hybrid MoS2-PVA nanocomposite and top Ag electrode are deposited by reverse offset, electrohydrodynamic (EHD) atomization and electrohydrodynamic (EHD) patterning respectively. The fabricated device displayed characteristic bistable, nonvolatile and rewritable resistive switching behavior at a low operating voltage. A decent off/on ratio, high retention time, and large endurance of 1.28 × 102, 105 sec and 1000 voltage sweeps were recorded respectively. Double logarithmic curve satisfy the trap controlled space charge limited current (TCSCLC) model in high resistance state (HRS) and ohmic model in low resistance state (LRS). Bendability test at various bending diameters (50-2 mm) for 1500 cycles was carried out to show the mechanical robustness of fabricated device. [ABSTRACT FROM AUTHOR]

A high performance humidity sensor for environmental and health monitoring has been fabricated using various combinations of molybdenum carbide (Mo 2 C) with polyacrylamide (PAM) and polyvinyl alcohol (PVA). The humidity sensing properties of pure Mo 2 C were compared with those of its composites with PAM and PVA. The response curves and working principle were investigated and novel bi-layered sensors were then fabricated to achieve highly linear and stable response for a wide range of humidity sensing (0% RH to 90% RH). The sensors having a bi-layer combination of Mo 2 C with PAM give a linear response with a sensitivity of 775 Ω/%RH and excellent repeatability. The working mechanism of the sensors allow them to be used with frequency response conversion read-out circuits and the results ascertain their linear and stable behavior. The response-time and recovery-time of the sensors were measured that gave average values of ∼1 s and ∼2.5 s respectively for the composites and ∼1.8 s and 2.3 s for the bi-layer configuration. The sensors are aimed to replace low performance complex and expensive sensors in the market for environmental and health monitoring applications. [ABSTRACT FROM AUTHOR]

Niobium and nitrogen co-doped titanium dioxide (Nb-N-TiO 2) semiconductor nanostructures were synthesized through a facile sol-gel protocol using titanium tetra iso-propoxide (TTIP), urea and niobium pentoxide as precursors followed by calcination at 450 °C for 4 h. The synthesized nanomaterial (Nb-N-TiO 2) was characterized via Fourier Transform Infrared (FTIR) and Raman spectroscopy, UV-Visible (UV-Vis) Spectroscopy, Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Brunauer-Emmett-Teller (BET) technique, Dynamic Light Scattering (DLS) technique and ZETA Potential analysis. The band gap of Nb-N-TiO 2 was reduced as compared to TiO 2 due to reduced space between valance and conduction band which also reduced the electron-hole (e-, h+) recombination and led to better photocatalytic activity of the Nb-N-TiO 2 as confirmed by TAUC plot. Photocatalytic activity of Nb-N-TiO 2 was investigated for degradation of methylene blue (MB) dye under sunlight as cheaper light source. Factors like dye concentration, dosage of catalyst, volume of solution time and pH were studied and optimized for MB degradation. Under finally optimized conditions, 97% of 25 ppm MB was degraded just in one minute using 45 mg of photocatalyst. The co-doped nanocatalyst, was re-used for MB degradation upto 4th cycle with its efficiency reduced to 75% which shows a better catalytic role by the catalyst. Degradation products of MB were recognized through electrospray ionization coupled mass spectroscopy (ESI-MS) and liquid chromatography coupled mass spectroscopy (LC-MS) techniques. The catalyst was also applied for MB degradation in tap water sample. [Display omitted] • The Nb-N-TiO2 photocatalytic nanomaterial was synthesized by simple facile sol-gel method. • The synthesized Nb-N-TiO2 photocatalyst was analyzed via advanced techniques. • The degradation of methylene blue dye was checked using sunlight as a renewable source of energy. • For the degradation of MB dye different parameters were optimized and reusability test was also performed. • The degradation pathway of MB dye was proposed by analyzing degraded products. [ABSTRACT FROM AUTHOR]