One-step Deposition Method Research Articles

A Highly Selective Acetone Sensor Based on Coal-Based Carbon/MoO2 Nanohybrid Material.

High temperature represents a critical constraint in the development of gas sensors. Therefore, investigating gas sensors operating at room temperature holds significant practical importance. In this study, coal-based porous carbon (C-700) and coal-based C/MoO2 nanohybrid materials were synthesized using a simple one-step vapor deposition and sintering method, and their gas-sensing performance was investigated. The gas-sensing performance for several VOC gases (phenol, ethyl acetate, ethanol, acetone, triethylamine, and toluene) and a 95% RH high-humidity environment were tested. The results indicated that the C/MoO2-450 sample sintered at 450 °C exhibited excellent specific selectivity towards acetone at room temperature, with a response value of 4153.09% and response/recovery times of 10.8 s and 2.9 s, respectively. Furthermore, the C/MoO2-450 sample also demonstrated good repeatability and long-term stability. The sensing mechanism of the synthesized materials was also explored. The superior gas-sensing performance can be attributed to the synergistic effect between the porous carbon and MoO2 nanoparticles. Given the importance of enhancing the high-tech and high-value-added utilization of coal, this study provides a viable approach for utilizing coal-based carbon materials in detecting volatile organic compounds at room temperature.

Long-lasting renewable antibacterial N-halamine coating enable dental unit waterlines to prevention and control of contamination of dental treatment water

Developing bacterial biofilm on the dental unit waterlines increases the risk of cross-infection among oral patients. Although chemical disinfectants can achieve disinfection effects in a short period of time, corrosion damage of dental unit waterlines and water contamination can also occur after continuous use of it. Herein, this study explored a one-step deposition method to prepare a durable and renewable antibacterial N-halamine polymeric coating on polyurethane waterlines. The method utilized polyelectrolyte complexes formed with polyethylenimine (PEI) and phytic acid (PA), followed by chlorination to activate the antibacterial properties. The N-halamine polymeric coating reduces the polyurethane waterline’s water contact angle, thus reducing biofouling deposits and the obstruction of the active halide site on the waterlines, thereby facilitating the maintenance of the cleanliness of the coating. In addition, benefiting both from the active chlorine release and the high density of positive charges on the coating, the polyurethane waterline antimicrobial activity is significantly enhanced. Besides, the N-halamine polymeric coating is biocompatible. This study showed that long-lasting and renewable antimicrobial requirements can be achieved by simple surface modification of N-halamine polymer coatings, which provides a practicable strategy for the production of long-term and reproducible antibacterial dental unit waterlines to reduce the incidence of hospital infection in oral department.

Dendrite-free Zn anode enabled by combining carbon nanoparticles hydrophobic layer with crystal face reconstruction toward high-performance Zn-ion battery

Aqueous zinc ion batteries (ZIBs) have been considered promising energy storage systems due to their excellent electrochemical performance, environmental toxicity, high safety and low cost. However, uncontrolled dendrite growth and side reactions at the zinc anode have seriously hindered the development of ZIBs. Herein, we prepared the carbon nanoparticles layer coated zinc anode with (103) crystal plane preferential oriented crystal structure (denoted as C@RZn) by a facile one-step vapor deposition method. The preferential crystallographic orientation of (103) crystal plane promotes zinc deposition at a slight angle, effectively preventing the formation of Zn dendrites on the surface. In addition, the hydrophobic layer of carbon layer used as an inert physical barrier to prevent corrosion reaction and a buffer during volume changes, thus improving the reversibility of the zinc anode. As a result. the C@RZn anode achieves a stable cycle performance of more than 3000 h at 1 mA cm−2 with CE of 99.77 % at 5 mA cm−2. The full battery with C@RZn anode and Mn-doped V6O13 (MVO) cathode show stability for 5000 cycles at the current density of 5 A g−1. This work provides a new approach for the design of multifunctional interfaces for Zn anode.

Sputtered Silicon-Coated Graphite Electrodes as High Cycling Stability and Improved Kinetics Anodes for Lithium Ion Batteries.

Amorphous Si thin films with different thicknesses were deposited on synthetic graphite electrodes by using a simple and scalable one-step physical vapor deposition (PVD) method. The specific capacities and rate capabilities of the produced electrodes were investigated. X-ray diffraction, scanning electron microscopy, Raman spectroscopy, profilometry, cyclic voltammetry, galvanostatic techniques, and in situ Raman spectroscopy were used to investigate their physicochemical and electrochemical properties. Our results demonstrated that the produced Si films covered the bare graphite electrodes completely and uniformly. Si-coated graphite, Si@G, with an optimal thickness of 1 μm exhibited good stability, with an initial discharge capacity of 628.7 mAhg-1, a capacity retention of 96.2%, and a columbic efficiency (CE) higher than 99% at C/3. A discharge capacity of 250 mAh g-1 was attained at a high current rate of 3C, which was over 2.5 times that of a bare graphite electrode, thanks to the high activated surface area (1.5 times that of pristine graphite) and reduced resistance during cycling.

Enhancement of Electrochemically Reduced Graphene Oxide (ErGO) UV Photo Detector Performance via Direct One-Step Electrode Deposition Technique

Recently, photodetectors have garnered significant attention owing to their broad spectrum of applications across fields such as the biomedical, industrial, agricultural, and telecommunications sectors. This research focuses on the development of a UV photodetector based on electrochemically reduced graphene oxide (ErGO) and incorporates reduced graphene oxide (rGO) thin films on interdigitated Au electrodes. The rGO thin films were synthesized using the direct one-step deposition method, maintaining a constant water bath temperature of 40 °C, and a consistent GO concentration of 0.15 g, while varying the pH levels within the range of pH 8 to pH 10. The investigation primarily concentrated on assessing the surface morphological, structural, and electrical properties of the rGO thin films by altering the pH level when exposed to 365 nm ultraviolet (UV) irradiation. The significant parameters for evaluating photodetector performance, including photosensitivity, stability, repeatability, response time, and recovery time. To achieve this, advanced techniques such as field-emission scanning electron microscopy (FESEM), Raman spectroscopy, and current-time measurement are employed. As a finding, the fabricated UV PD of rGO-Au at pH 9 achieved the photosensitivity 96.5% with the stability that was 30 times greater than rGO-Au (pH 10) and superior repeatability as well as rapid switching rate as compared to pH 8 and pH 10 with 0.6 V bias. This implies that rGO-Au prepared at pH 9 is a suitable material for application in UV detection.

Highly Orientated Sericite Nanosheets in Epoxy Coating for Excellent Corrosion Protection of AZ31B Mg Alloy.

The growing demands for material longevity in marine environments necessitate the development of highly efficient, low-cost, and durable corrosion-protective coatings. Although magnesium alloys are widely used in the automotive and aerospace industries, severe corrosion issues still hinder their long-term service in naval architecture. In the present work, an epoxy composite coating containing sericite nanosheets is prepared on the AZ31B Mg alloy using a one-step electrophoretic deposition method to improve corrosion resistance. Due to the polyetherimide (PEI) modification, positively charged sericite nanosheets can be highly orientated in an epoxy coating under the influence of an electric field. The sericite-incorporated epoxy coating prepared in the emulsion with 4 wt.% sericite exhibits the highest corrosion resistance, with its corrosion current density being 6 orders of magnitude lower than that of the substrate. Electrochemical measurements and immersion tests showed that the highly orientated sericite nanosheets in the epoxy coating have an excellent barrier effect against corrosive media, thus significantly improving the long-term anti-corrosion performance of the epoxy coating. This work provides new insight into the design of lamellar filler/epoxy coatings with superior anticorrosion performance and shows promise in the corrosion protection of magnesium alloys.

In-depth study of the effect of annealing temperature on the structural, chemical, and optical properties of MAPI thin films prepared by a one-step deposition method

In-depth study of the effect of annealing temperature on the structural, chemical, and optical properties of MAPI thin films prepared by a one-step deposition method

One-Step Preparation of Semiconductor/Dielectric Bilayer Structures for the Simulation of Flexible Bionic Photonic Synapses.

Flexible synaptic devices with information sensing, processing, and storage functions are indispensable in the development of wearable artificial intelligence electronic systems. Here, a semiconductor/dielectric bilayer structure was prepared by a one-step deposition method and used for the first time in a flexible biomimetic photonic synaptic transistor device. Specifically, poly(3-hexylthiophene)-block-poly(phenyl isocyanide) with pentafluorophenyl ester (P3HT-b-PPI(5F)) was prepared as the device active layer, where the P3HT segment served as a carrier transport channel and optical gate and the PPI(5F) segment was used for charge trapping. Various biomimetic synaptic behaviors, such as excitatory postsynaptic currents, paired-pulse facilitation, and short-term/long-term memory, were successfully simulated under green light stimulation. An ultra-low energy consumption of 1.82 fJ was achieved with a greatly reduced operating voltage. Further, the "Morse-code" optical decoding was simulated using the excellent synaptic plasticity of the device. In addition, flexible synaptic devices were prepared by a one-step deposition method and can be well-affixed to arbitrary substrates. This has promising applications in the field of wearable bionic electronics.

High energy storage performance MnSe2 cathode by one-step deposition strategy in aqueous zinc-ion batteries

The directly synthesized MnO2 using ambient temperature aqueous solution deposition strategy has great application prospects as the cathode material for aqueous zinc-ion batteries, which strategy has the advantages of simple process, large-scale and reproducible production. However, the single MnO2 suffers many problems, such as poor practical energy density and serious capacity fading. In order to improve the capacity and cycling stability of the cathode, we designed to use the method of ambient temperature aqueous solution deposition strategy. Using this method and adding a reducing agent and selenide to the original raw materials for the preparation of MnO2, the crystalline state of MnSe2 materials was finally synthesized creatively. This in situ one-step deposition method for the synthesis of MnSe2 is a very simple process and can be prepared on a large scale in a short period of time, saving time and effort. Compared with the MnO2 cathode materials, the MnSe2 cathode can reach the high capacity of 452.4 mAh g−1 at a low current density of 0.1 A g−1, an excellent rate capability of 242.7 mAh g−1 at 2.0 A g−1. After 2000 cycles (2 A g−1) of charging and discharging, the Zn/MnSe2 battery can maintain a specific capacity of over 231.5 mAh g−1 and a superior cycling retention of 86.3%, with a coulombic efficiency remains above 98%. This work provides a new way to develop simple, high-capacity and long-life aqueous zinc-ion batteries.

Successful 2D MoS2 nanosheets synthesis with SnSe grid-like nanoparticles: Photoelectrochemical hydrogen generation and solar cell applications

Preparing a two-dimensional (2D) lateral heterostructure film with n and p-type materials in the same film with high control distribution remains challenging so far. In this paper, a lateral heterostructure film based on 2D MoS2 nanosheets (NSs) with SnSe nanoparticles (NPs) “ SnSe/MoS2 ” is prepared via a facile one-step electrophoretic deposition method. MoS2 NSs are stacked vertically to form a film while SnSe NPs are incorporated to form nanoparticles of geometric grid-like inside the film. The film structure was confirmed through a scanning electron microscope. Such a heterostructure improves the performance of PEC hydrogen generation due to the fast separation of electron-hole pairs and hindering recombination. The short-circuit current density (JSC), as well as the open circuit voltage (VOC) of heterostructure film, reaches 1.75 mA cm−2 and 0.17 V, respectively, under a visible light illumination of 100 mW cm-2. The produced (Jph) values increase from 0.52 to 1.75 mA cm−2 under a light intensity ranging from 10 to 100 mW.cm−2, respectively. The grid-like structure of the SnSe/MoS2 heterostructure advantages its application for solar cells owing to the important potential difference that ensures the formation of p and n-type materials in the same film. This is the aim of our future work, where a complete synthesis of solar cells with high efficiency will be given, in which the p and n types of materials will face the sunlight directly.

One-Step Synthesis of Ultrathin Zeolitic Imidazole Framework-8 (ZIF-8) Membrane on Unmodified Porous Support via Electrophoretic Deposition.

Metal-organic frameworks (MOFs) are regarded as the next-generation, disruptive membrane materials, yet the straightforward fabrication of ultrathin MOF membranes on an unmodified porous support remains a critical challenge. In this work, we proposed a facile, one-step electrophoretic deposition (EPD) method for the growth of ultrathin zeolitic imidazole framework-8 (ZIF-8) membranes on a bare porous support. The crystallinity, morphology and coverage of ZIF-8 particles on support surface can be optimized via regulating EPD parameters, yet it is still difficult to ensure the integrity of a ZIF-8 membrane with the constant voltage mode. In contrast, the constant current mode is more beneficial to the growth of a defect-free ZIF-8 membrane due to the steady migration rate of colloid particles toward the electrode. With a current of 0.65 mA/cm2 and deposition time of 60 min, a 300 nm thick ZIF-8 membrane was obtained, which exhibits a CO2 permeance of 334 GPU and a CO2/CH4 separation factor of 8.8, evidencing the defect-free structure.

Facile Preparation of Flexible Lateral 2D MoS2 Nanosheets for Photoelectrochemical Hydrogen Generation and Optoelectronic Applications

Two-dimensional (2D) materials have attracted significant attention with their high optical response due to their interesting and unique fundamental phenomena. A lateral 2D MoS2 nanosheets was prepared via a facile one-step electrophoretic deposition method on polyethylene terephthalate (PET)/ITO. These nanosheets have been used as photoelectrode materials for photoelectrochemical (PEC) hydrogen generation and optoelectronics. The chemical structure and morphology were confirmed using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), Raman, scanning electron microscope (SEM), and transmission electron microscopy (TEM). The optical absorbance of the 2D MoS2 nanosheets extended to the UV, Vis, and near-IR regions with a bandgap value of 1.59 eV. The testing of the prepared photoelectrode material, PET/ITO/MoS2, was carried out through a three-electrode system, in which the current density (Jph) value represents the rate of H2 gas evaluated. The Jph enhanced under light illumination compared to the dark conditions with values of 0.4 to 0.98 mA·cm−2, respectively. The produced photocurrent at V = 0 V was 0.44 mA·cm−2. This confirms the great abilities of the PET/ITO/MoS2 photoelectrode in light detection and hydrogen generation with high photoresponsivity values. Soon, our team will work on the development of a prototype of this three-electrode cell to convert the water directly into H2 fuel gas that could be applied in houses and factories, or even in advanced technology such as spacecraft and airplane F-35s by providing H2 gas as a renewable energy source.

Chlorine-terminated MXene quantum dots for improving crystallinity and moisture stability in high-performance perovskite solar cells

In n-i-p planar perovskite solar cells, high-crystallinity perovskite film and long-term stability against high humidity are critical for high photovoltaic performance and future commercialization. In this work, the Cl-terminated Ti3C2 quantum dots (denoted as Ti3C2Clx QDs) are introduced as additives in perovskite precursor solution by one-step deposition method. The strong interaction between the Cl terminations of Ti3C2Clx QDs and Pb2+ ions can retard the crystallization rate and induce the preferred grain orientation during the film crystallization process, thus delivering a high-quality perovskite film with high crystallinity, fewer trap-states, and smaller residual tensile strain. Meanwhile, due to its top–bottom increasing gradient distribution, the addition of Ti3C2Clx QDs can also accelerate the charge extraction and benefit band alignment between the tin oxide (SnO2) electron transport layer (ETL) and the perovskite layer. As a result, the device with Ti3C2Clx QDs can achieve an enhanced efficiency of 21.31% with an ultrahigh open-circuit voltage of 1.19 V and negligible hysteresis. In addition, by substituting the OH terminations of Ti3C2Tx, Cl-terminated Ti3C2Clx QDs can avoid possible deprotonation of protonated organic amine in perovskite, improving the overall stabilities. As a result, the unencapsulated device can exhibit outstanding long-term humidity stability by maintaining over 84% of its initial PCE after being aged for 1000 h under 40% relative humidity in the dark at room temperature.

Relationship between hydrophobicity and drag reduction of SiO2/HLR-Si coatings

The one-step spraying deposition method using hydrophobic SiO2 and fluorine-silicone resin (HLR-Si) was adopted in this paper to prepare the hydrophobic micro-nanoscale hierarchical structure on the surface of the test sample. Scanning electron microscopy and atomic force microscopy were used to characterize the surface morphology of the coating, and the contact angle meter was employed to evaluate the surface wettability. The content of hydrophobic silica produced on the hydrophobic performance of the coating was studied, and the relationships between hydrophobic performance and drag reduction performance were investigated. Results show that the one-step spraying deposition method is a simple and efficient technique for coating preparation. The maximum contact angle of SiO2/HLR-Si coating is 163°, and the sliding angle is only 1.8°. Compared with the 96° pure HLR-Si resin coating, the maximum drag reduction rate of the prepared superhydrophobic coating is 23.4%. Furthermore, the water resistance increases with the contact angle when the contact angle is less than 150°, while the drag reduction effect is improved with the increase of the contact angle when the contact angle is larger than 150°. However, the effect of drag reduction disappears when the rotation speed is excessively high. Finally, results verified that the air film captured by the superhydrophobic surface can reduce the water resistance through the method of artificial air supplement.

Effect of chlorine and bromine on the perovskite crystal growth in mesoscopic heterojunction photovoltaic device

Organic-inorganic hybrid perovskite solar cells are within the emerging photovoltaic technologies. The combination of different halogen ions, in certain fill fractions, is one of the methods to improve the perovskite film properties. Herein, fabrication and characterization of perovskite cells in standard mesoscopic architecture using one-step deposition method has been done. The role of the halogen ions (Chlorine or Bromine) on crystal structure growth and photoelectric performance has been investigated. X-ray diffraction, scanning electron microscopy, atomic force microscopy and optical microscopy analysis were performed. The microstructure, composition and morphology of CH3NH3PbI1.8Br1.2 and CH3NH3PbI1.8Cl1.2 films are dissimilar, although identical fabrication method was used. Same holds for optical properties, band gap energies of 1.84 eV and 1.63 eV, respectively, being obtained. Integrated in solar cells, the maximum power conversion efficiency of the Br based devices is beyond 10%, while for those based on Cl, the efficiency drops around 5%.

A one-step deposition method to prepare separators with carbon soot loading for lithium-sulfur battery

A one-step deposition method to prepare separators with carbon soot loading for lithium-sulfur battery

One-step anodization-electrophoretic deposition of titanium nanotubes-graphene nanoribbon framework for water oxidation

• New strategy for graphene nanoribbon framework deposition over TNT. • Straightforward one-step anodization-electrophoretic deposition method. • Enhanced performance as photoanode relative to pristine TNT electrode. • Higher charge carrier separation and slightly valence band maximum shift. Self-supported titanium nanotubes (TNT) is one of the most interesting materials for environmental applications. However, its major hurdle is the low absorption throughout the visible range; therefore, high rate of exciton separation is hardly archived. We introduce a new strategy to incorporate a graphene nanoribbon framework (GNF-1), a subclass of porous organic polymer, onto TNT by means of a one-step anodization-electrophoretic deposition assisted by the anionic surfactant sodium dodecyl sulfate. This approach leads to the formation of an effective interface between the TNT and GNF-1 based on the simultaneous anodic growth of nanotubular TiO 2 and the electrophoretic-driven motion of the negatively charged GNF-1-surfactant colloids. The use of an anionic surfactant is mandatory to attract the charge neutral GNF-1 to the anode and can be easily expanded to other porous organic polymers. The TNT-GNF-1 electrode exhibits enhanced performance as a photoanode, with an increase in photocurrent density up to 45% relative to pristine TNT electrode. This result is related to the higher charge separation and the slightly valence band maximum shift, which is beneficial for transfer of charge carriers for water oxidation. The faradaic efficiency of both the pristine TNT and TNT-GNF-1 photoanodes to generate O 2 is 70% according to a collector-generator dual electrode system, demonstrating that the increase in photocurrent response of TNT-GNF-1 photoanodes is not due to oxidation of GNF-1, but from the synergic effect between the materials.

Application of chitosan-N-doped graphene oxide ion-imprinted sensor in Cd (II) ions detection

In this paper, a cheap, stable, and sensitive chitosan-N-doped graphene oxide (N-RGO) ion-imprinted sensor (IIP-Cd) was studied. The copolymer was deposited on the surface of the glassy carbon electrode (GCE) by the one-step deposition method, and IIP-Cd was obtained after eluted the target ions. XRD, FT-IR, SEM, and EDS were used to characterize the structure and morphology of different materials. The electrochemical properties of IIP-Cd were evaluated by cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. The linear range of the sensor was 0.01-0.1 μM, and the detection limit was 3.51 nM (S/N = 3), and the sensor has high sensitivity, good reproducibility, and well stability. Besides, IIP-Cd still has high selectivity for Cd (II) in mixed ion solution (Zn(II), Hg(II), Cu(II), Cd(II), Mn(II), Ni(III)). The target ion cavity formed in IIP- Cd and the N-RGO as the substrate improves the electron transmission rate of the electrochemical sensor, thus realizing the green, environment-friendly, efficient and sensitive detection with low-cost raw materials in practical application.

Flexible Supercapacitors Based on CNT/MnO2-BP Composite Yarn Synthesized by In Situ Reduction

Solid-state flexible supercapacitors are considered significant prospective energy storage devices, and carbon nanotube (CNT) yarn is an ideal electrode material for constructing linear flexible supercapacitors because of its high electrical conductivity and flexibility. However, the relatively low specific capacitance and energy density of a supercapacitor made of pure CNT yarn limits its application. Here, we prepared a CNT/MnO2-BP composite yarn via a facile one-step liquid deposition method by the innovative introduction of few-layer black phosphorous (BP) nanosheets. The redox reaction between the BP and the potassium permanganate forms MnO2 and an electrolyte of phosphorus acids (HxPOy). The two-ply yarn supercapacitor composed of the CNT/MnO2-BP composite yarn shows excellent electrochemical properties with a volumetric capacitance of 441.79 F cm−3 at the scanning rate of 0.01 V s−1 and an energy density of 9.82 mWh cm−3 at a power density of 441.79 mW cm−3. Herein, this work provides a way to improve the electrochemical performance of CNT yarn-based supercapacitors that can act as flexible energy storage devices for wearable electronics.

Rational engineering of hierarchical mesoporous CuxFeySe battery-type electrodes for asymmetric hybrid supercapacitors

Highly-ranked positive electrode materials with distinct electrochemical properties and appropriate designs of heterostructured porous architectures integrating mixed transition metal selenides are necessary to boost energy storage capability, which thus have been intensively investigated in the recent years. In this work, we develop a one-step chemical deposition method to grow 3D copper iron selenides (CuxFeySe) heterostructures on the surface of a nickel foam (NF) current collector. The macroporous skeleton of NF not only boosts the homogeneous growth of CuxFeySe architectures but also improves the electrical conductivity of resultant electrodes due to the robust mechanical strength at the junction. The effect of Cu2+/Fe2+ ions is also investigated and noticeably contributed to electrochemical performance. Benefitting from the synergetic effect of integrated Cu and Fe ions with different chemical states, improved electronic configuration, and effective electron/ion transport rate, the battery-type Cu7.5Fe7.5Se electrode delivers a high specific capacity of 186.1 mAh g−1 at a current density of 1 A g−1 with an enhanced capacity retention (63.7% at 50 A g−1). Moreover, the asymmetric supercapacitor (ASC) device fabricated with the self-standing Cu7.5Fe7.5Se electrode and benchmark activated carbon (AC) as the positive and negative electrodes, respectively realizes a large cell potential of 1.5 V and exhibits a high specific capacity of 70 mAh g−1 at 1 A g−1 and a good rate capability (61.6% at 25 A g−1). The assembled device reaches a maximum energy density of ~74.2 W h kg−1 at a power density of 1058.3 W kg−1 together with an appropriate lifespan (91.3% after 8000 cycles at 12 A g−1).