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The detection of heavy metals in water, especially Pb2+ ions, is important due to their severe hazardous effects. To address this issue, a highly controlled hexagonal TiON/TiO2 heterostructure has been synthesized in this study. The fabrication process involved the utilization of atomic layer deposition and direct current sputtering techniques to deposit TiO2 and TiON layers onto a porous Al2O3 membrane used as a template. The resulting heterostructure exhibits a well-ordered hollow tube structure with a diameter of 345 nm and a length of 1.2 µm. The electrochemical sensing of Pb2+ ions in water is carried out using a cyclic voltammetry technique under both light and dark conditions. The concentration range for the Pb2+ ions ranges from 10–5 to 10–1 M. The sensitivity values obtained for the sensor are 1.0 × 10–6 in dark conditions and 1.0 × 10–4 in light conditions. The remarkable enhancement in sensitivity under light illumination can be attributed to the increased activity and electron transfer facilitated by the presence of light. The sensor demonstrates excellent reproducibility, highlighting its reliability and consistency. These findings suggest that the proposed sensor holds great promise for the detection of Pb2+ ions in water, thereby facilitating environmental monitoring, water quality assessment, and safety regulation across various industries. Furthermore, the eco-friendly and straightforward preparation techniques employed in its fabrication provide a significant advantage for practical and scalable implementation. [ABSTRACT FROM AUTHOR]

The flower-like Cr2O3−Cr(OH)3/poly-2-chloroaniline (P2CA) nanocomposite is synthesized through oxidative polymerization of 2CA using K2Cr2O7, with the preparation process performed on a polypyrrole (Ppy) seeding film. SEM images show that the P2CA material has a tissue-like structure, with fibers exhibiting a great degree of behavior. The Cr2O3−Cr(OH)3/P2CA composite displays a large porous structure with flower-shaped properties and a slotted behavior, featuring circular empty holes, with nanoparticles having a pore structure ranging from 5 to 100 nm. The calculated bandgap values for P2CA and Cr2O3−Cr(OH)3/P2CA are 2.02 and 1.87 eV, respectively. The Cr2O3−Cr(OH)3/P2CA composite photoelectrode is utilized for hydrogen gas production from sewage water, with the produced current density (Jph) reflecting the hydrogen generation rate. The Jph value in on/off light conditions demonstrates a significant enhancement under light of 0.002 and 0.018 mA.cm−2, correspondingly. Furthermore, the Jph increases from − 0.005 to − 0.006 mA.cm−2 at 340 and 730 nm, respectively, indicating the responsivity of this composite in the infrared region. So, the results demonstrate the potential of the Cr2O3−Cr(OH)3/P2CA nanocomposite photoelectrode as a cost-effective and efficient alternative for the production of hydrogen gas, without the limitations associated with previous materials and techniques. [ABSTRACT FROM AUTHOR]

The porous-spherical MnO2-Mn(OH)2/Ppy (polypyrrole) nanocomposite is synthesized through a one-pot, cost-effective oxidative polymerization method using KMnO4. This synthesis technique demonstrates great promise in terms of its ability to achieve mass production of the nanocomposite. The nanocomposite has a great optical property related to its wide optical absorbance from UV to near IR region (250 till 730 nm). The electrical properties of the MnO2-Mn(OH)2/Ppy nanocomposite photodetector were systematically tested under various optical conditions. Through these measurements, the performance of the photodetector was evaluated and characterized. The current density (Jph) is used to estimate the sensitivity of the generated electrons under the photon's irradiation. Under off/on light, the produced Jph are 4.2 and 9.5 mA cm−2, correspondingly. While, as the wavelengths increase from 340 to 730 nm, the Jph values exhibit a decrease, declining from 0.34 to 0.28 mA/cm². This trend illustrates the nanocomposite excellent responsiveness to photons across a wide range of optical regions. The promising sensitivity related to the photoresponsivity (R) of of 3.42 mA W−1. These values are estimated through detectivity (D) calculation, in which the D value is 6.42*108 Jones. With its exceptional reproducibility, the developed photodetector demonstrates strong suitability for industrial applications. Additionally, its synthesis process incurs low costs, further enhancing its attractiveness for practical implementation in various industries. [ABSTRACT FROM AUTHOR]

The primary objective of this research is to address the energy challenges by introducing an innovative nanocomposite material. This material is designed to facilitate the conversion of environmentally friendly and economically viable Red Sea water into hydrogen gas. The ultimate goal of this work is to pave the way for the development of a practical device that can be employed within households and industrial settings to directly convert water into hydrogen gas. This novel nanocomposite material synthesized through oxidative polymerization comprises As2O3 and Poly-3-methylaniline (P3MA). This material possesses an extensive absorption range, spanning up to 700 nm, and features a bandgap of 1.75 eV, making it a promising candidate for use as a photoelectrode in green hydrogen production. The unique aspect of this setup lies in the utilization of Red Sea water, a natural sacrificing agent, as the electrolyte, rendering the process eco-friendly and cost-effective. When it is employed as a photoelectrode, this material exhibits high sensitivity to green hydrogen production, generating 6 moles/10 cm2·h of hydrogen. At a voltage of −0.83 V, the current density values are measured as −0.08 mA·cm−2 (Jph) in light and −0.02 mA·cm−2 (Jo) in darkness. Furthermore, the photoelectrode's responsiveness to light is assessed with different optical filters, revealing the optimal performance at 340 nm, where Jph reaches −0.052 mA·cm−2. These outcomes provide strong evidence of the photoactivity of the As2O3/P3MAphotoelectrode for green hydrogen production using Red Sea water. This underscores its potential for the development of an electrochemical cell for the direct conversion of sea water into H2 gas. [ABSTRACT FROM AUTHOR]

The ZnS–ZnO/graphitic carbon nitride (g-C3N4) nanocomposite was synthesized using the hydrothermal method, incorporating 0.05 g of g-C3N4 during the composite formation. The crystalline nature of the materials was confirmed through X-ray diffraction analysis. Scanning electron microscope and transmission electron microscope analyses revealed the morphological properties of the materials. The nanocomposite exhibited 2D g-C3N4 nanosheets with a thickness of 7.8 nm. Additionally, the nanocomposite consisted of spherical particles with an average particle size of 15 nm, which were distributed over the 2D g-C3N4 sheets. ZnS–ZnO/g-C3N4 nanocomposite consists of spherical particles with an average particle size of 15 nm that covers the 2D g-C3N4 sheets. ZnS–ZnO/g-C3N4 nanocomposites without/with polypyrrole are used as a paste for the two-symmetric electrodes hybrid supercapacitor. The charge (0.5 to 1.3 A/g), cyclic voltammetry (0.0 to 1.0 potential window), impedance, and stability for the prepared supercapacitor are studied using electrochemical measurements. ZnS–ZnO/g-C3N4 supercapacitors have a specific capacitance of 15.1 and 152.2 F/g without/with the physical addition of polypyrrole, respectively. Also, they have energy density values of 1.17 and 11.87 W h/kg, respectively. Through the Randles cell, The Rs in the supercapacitor without/with polypyrrole are 6.9 and 6.65 Ω, respectively. While the values of the semicircle diameter (Rct) are 0.37 and 0.25 Ω, respectively. Also, the capacitance retention values are 88.6 and 90.2% without/with polypyrrole addition until 500 runs of charge/discharge. These values confirm the behavior of the polypyrrole material in the enhancement of the supercapacitor efficiency, storage capacity, and stability. [ABSTRACT FROM AUTHOR]

A highly uniform spherical MoO2-MoO3/polypyrrole core-shell nanocomposite has been successfully synthesized as an optoelectronic photon sensing material, capable of detecting light in the UV, Vis, and IR domains. The nanocomposite is prepared through the oxidation of pyrrole using Na2MoO4, resulting in a uniform spherical morphology that has been confirmed by TEM, theoretical modeling, and SEM analyses. This morphology contributes to its promising optical behavior, characterized by a small bandgap of 1.36 eV. The optoelectronic photosensing capability of the nanocomposite has been evaluated across the UV, Vis, and IR spectra, demonstrating high efficiency. The photoresponsivity R values indicate the ability of the nanocomposite to generate hot electrons in response to incident photons. With an R value of 4.15 mA·W−1 at 440 nm, this optoelectronic device exhibits considerable promise for integration into an advanced technological apparatus. The detection (D) value of 9.30 × 108 Jones at 440 nm further confirms the high sensitivity in the Vis region. The excellent stability of the device can be attributed to the inherent MoO2-MoO3 oxide and Ppy polymer materials. This stability has been demonstrated through reproducibility studies and current-voltage measurements under various optical conditions. The combination of stability, efficiency, and sensitivity makes this optoelectronic device well suited for light sensing applications in both industrial and commercial settings. Its promising performance opens up opportunities for advancements in various fields requiring accurate and reliable light detection. [ABSTRACT FROM AUTHOR]

β-Ni(OH)2/graphitic carbon nitride (G-C3N4) nanocomposite and brain-like shape polypyrrole are prepared using hydrothermal and oxidative polymerization, respectively. XRD, XPS, SEM, and TEM display the elemental, crystalline, and morphological properties of these nanomaterials. The SEM confirms the preparation of 2D sheets of G-C3N4 and brain-like shape polypyrrole. The hybrid supercapacitor is fabricated without/with the incorporation of polypyrrole material and then evaluated through the study of the electrochemical parameters of charge and cyclic voltammetry. The applications in a supercapacitor are carried out through the synthesis two-symmetric hybrid supercapacitor. There are enhancements in the cyclic voltammetry behavior after polypyrrole incorporation with the β-Ni(OH)2/G-C3N4 nanocomposite. At 0.3 A/g, the electrochemical charge is 122 and 142 s without/with the physical incorporation of polypyrrole, correspondingly. The supercapacitor specific capacitance (CS) values are 101 and 120 F/g without/with polypyrrole, respectively. Moreover, the retention stability is enhanced from 85.6 to 90.2% after polypyrrole addition, till 500 cycles. Soon, a prototype of this supercapacitor will be synthesized for industrial applications. [ABSTRACT FROM AUTHOR]

This study highlights the utilization of the Cr2S3-Cr2O3/P2ABT nanocomposite photoelectrode for efficient and highly sensitive photon absorption, enabling the generation of green hydrogen through the production of hot electrons upon illumination. The nanocomposite is synthesized via a one-pot reaction using K2Cr2O7 and 2-aminobenzene-1-thiol monomer, and the presence of Cr2S3-Cr2O3 is confirmed by XRD and XPS analysis within the composite. The optical properties of the Cr2S3-Cr2O3/poly-2-aminobenzene-1-thiol composite exhibit wide spectral coverage from UV to IR, with a bandgap of 1.6 eV. The diverse morphological behavior observed in the composite correlates with its optical properties, with the cleft spherical particles of the pure polymer transforming into rod-like structures embedded within the polymer matrix. The generated hydrogen gas demonstrates an impressive efficiency of 40.5 mole/10.cm2.h through electrochemical testing. The current density (Jph) values are evaluated under different light frequencies using optical filters ranging from 730 to 340 nm, resulting in Jph values of 0.012 and 0.014 mA.cm−2, respectively. These findings present a promising avenue as green hydrogen for industrial applications, leveraging the potential of the Cr2S3-Cr2O3/P2ABT nanocomposite photoelectrode. [ABSTRACT FROM AUTHOR]

This study utilized the exceptional optical and electrical properties of polypyrrole (Ppy) to fabricate high-performance optoelectronic devices. The synthesis of the porous-spherical Cr2O3-Cr(OH)3-Ppy/Ppy nanocomposite thin film was achieved by preparing a second thin film of Cr2O3-Cr(OH)3-Ppy on the initial Ppy film using K2Cr2O7 as an oxidant. The nanocomposite's properties were thoroughly characterized, including XRD and optical absorbance analyses. The XRD analysis showed that the crystalline size of the nanocomposite was 20 nm, while optical absorbance analysis demonstrated that the nanocomposite had a higher absorbance in a wide optical range compared to Ppy nanomaterials, as evidenced by the enhancement in bandgap (Eg) value from 3.33 eV for Ppy to 1.89 eV for Cr2O3-Cr(OH)3-Ppy. The fabricated nanocomposite thin film exhibited excellent light-sensing behavior, as evidenced by the evaluation of Jph values under different light conditions and various monochromatic lights with a detectivity (D) of 3.6 × 106 Jones (at 340 nm). The device demonstrated its potential as a solar cell, with a short circuit current (JSC) of 13 µA and an open circuit voltage (VOC) of 1.91 V. Given the nanocomposite's low cost, high technical production, and superior optoelectronic properties, it has significant potential for use in commercially available high-tech devices. [ABSTRACT FROM AUTHOR]

A Ag2S-Ag2O-Ag/poly-2-aminobenzene-1-thiol (P2ABT) nanocomposite was prepared using the photopolymerization reaction using AgNO3 as an oxidant. The size of the nanocomposite was about 40 nm, in which the morphology was confirmed using TEM and SEM analyses. The functional groups of Ag2S-Ag2O-Ag/P2ABT were confirmed using FTIR; also, XRD confirmed the inorganic Ag2S, Ag, and Ag2O formation. This nanocomposite has great performance in supercapacitor applications, with it tested in acidic (1.0 M HCl) and basic mediums (1.0 M NaOH). This pseudo-capacitor has great performance that appeared through the charge time in an acid medium in comparison to the basic medium with values of 118 s and 103 s, correspondingly. The cyclic voltammetry (CV) analysis further confirmed the excellent performance of the supercapacitor material, as indicated by the large area under the cyclic curve. The specific capacitance (CS) and energy density (E) values (at 0.3 A/g) were 92.5 and 44.4 F/g and 5.0 and 2.52 W·h·Kg−1 in the acidic and basic mediums, correspondingly. The charge transfer was studied through a Nyquist plot, and the produced Rs values were 4.9 and 6.2 Ω, respectively. Building on these findings, our objective is to make a significant contribution to the progress of supercapacitor technology through a prototype design soon. [ABSTRACT FROM AUTHOR]

Polypyrrole (Ppy) and Ppy/Ni(OH)2‐NiO nanocomposite are prepared through the in situ polymerization oxidation reaction (on glass), in which the composite is formed through the oxidation of NiSO4. The prepared materials were characterized to reveal their morphology, chemical structure, and optical properties. The Ppy and Ppy/Ni(OH)2‐NiO have average particle sizes of 160 and 250 nm, respectively. Moreover, the bandgap values are 1.70 and 1.44 eV, respectively. Through the composite, the polymer acts as a shell (40 nm), while the Ni(OH)2‐NiO is the core. Analysis of the Ppy illustrates that the crystalline nature of the polymer increases after the composite formation, in which the pure Ppy has no sharp peaks, while the characteristic two peaks are formed after the composite formation. Moreover, a hexagonal Ni(OH)2 is confirmed inside the composite. The applications of the glass/Ppy and glass/Ppy/Ni(OH)2‐NiO are carried out as optoelectronic devices, in which the testing is carried out under light/dark and monochromatic wavelengths light, the Jph values are 0.12 and 0.85 mA·cm−2, respectively. The photoresponsivity (R) for the composite optoelectronic is 12.5 mA·W−1 while the detectivity (D) is 2.79*1011 Jones. [ABSTRACT FROM AUTHOR]