Electrochemical Deposition Route Research Articles

Hierarchical network-like Ni-Mn-S/NiMn-LDH nanostructure as efficient electrode material for high-rate and long cycle life hybrid supercapacitors

In the present work, we have developed a facile binder-free approach to design a hierarchical network-like nanostructure electrode onto the nickel foam (NF) using the combination of hydrothermal synthesis followed by an electrochemical deposition route. Based on the physicochemical properties and the electrochemical measurements, the integrated Ni-Mn-S/NiMn-LDH electrode delivers an extremely good specific capacitance of 2611.8F/g at 1 A/g and superior cyclic stability with 90.7 % capacitance retention after 10,000 cycles, along with 98.9 % coulomb efficiency. Accordantly, benefiting from the combination of structural and compositional advantages along with the multivalent state of Ni and Mn elements provide more active sites, prominent synergy, and short ion transport paths, which impressively improved the electrochemical performance of Ni-Mn-S/NiMn-LDH. Likewise, the assembled Ni-Mn-S/NiMn-LDH/NF//AC asymmetric device displays an excellent electrochemical behavior with a high energy density of 60.9 Wh kg−1 at a significant power density of 800 W kg−1 alongside the superior life-stability. Furthermore, nine blue LED indicators can be lit up for 1500 s when two ASCs connected in parallel. These results render an optimistic prospect of the Ni-Mn-S/NiMn-LDH in electrode materials for practical application in developing energy storage systems.

In situ prepared amorphous VOH-Polyaniline@Carbon cloth as cathodes for high performance zinc ion batteries

Vanadium-based compounds are promising cathode materials for aqueous zinc ion batteries (AZIBs) while suffering from notorious poor conductivity and structural instability, leading to severe performance degradation.Herein, we grew polyaniline intercalated VOH nanoarrays on conductive carbon cloth (VOH-PANI@CC) via one-step electrochemical deposition route. Owing to the advantageous nature of amorphous structure of VOH, good conductivity of PANI and the strong synergistic effect between two components, the VOH-PANI@CC free-standing electrodes showed abundant ion diffusion paths, plentiful ion storage sites and high conductivity. The electrode thus achieves an initial charging capacity up to 500 mAh g−1 at 0.1 A g−1 and can still maintain 117.4 mAh g−1 for 500 cycles at 0.5 A g−1. Furthermore, ex-situ XRD and XPS studies revealed the zinc storage process of VOH-PANI@CC and underlying mechanism of the enhanced performance. This work provides a universality design strategy for designing advanced high-performance V-based cathodes for AZIBs.

Synergic effects of FeOOH and CoNi2Se4 bilayer nanosheets as highly efficient electrocatalysts for the oxygen evolution reaction

The substantial growth of nonprecious and inexpensive electrocatalysts for the oxygen evolution reaction (OER) is vital for commercial usage. In this work, cobalt nickel selenide (CoNi2Se4, called CNSe) thin film nanosheet heterojunctions with iron oxyhydroxide (FeOOH) thin film nanosheets were grown directly on a nickel foam substrate (Ni-foam) using an electrodeposition method. The electrocatalytic activity of CNSe/FeOOH bilayer nanosheets was evaluated for OER studies using its CNSe and FeOOH counterparts. The CNSe/FeOOH bilayer thin film exhibited a low overpotential of 222 mV to deliver a benchmark current density of 10 mA cm−2, which was lower than that of the CNSe (327 mV) and FeOOH (276 mV) electrocatalysts. The bilayer electrocatalyst delivered remarkable long-term electrochemical stability for more than 120 h at a constant current density of 10 mA cm−2. The excellent activity was attributed to the synergic effects of CNSe/FeOOH with high electrochemical active sites and feasible charge transfer ability. This study provides new insights for designing a different class of materials using a simple electrochemical deposition route for high-performance OER kinetics.

A Study of the WO3/GO Electrochromic Films Obtained by the Electrochemical Deposition Route: Optical and Electromagnetic Method

A Study of the WO3/GO Electrochromic Films Obtained by the Electrochemical Deposition Route: Optical and Electromagnetic Method

Aqueous Zn-MnO2 battery: Approaching the energy storage limit with deep Zn2+ pre-intercalation and revealing the ions insertion/extraction mechanisms

Rechargeable aqueous zinc ion batteries (AZIBs) were considered as one of the most promising candidates for large-scale energy storage due to the merits of high safety and inexpensiveness. As AZIBs cathode material, MnO2 possesses great merits but was greatly hindered due to the sluggish diffusion kinetic of Zn2+ during electrochemical operations. Herein, deep Zn2+ ions intercalated δ-MnO2 (Zn-MnO2) was achieved by the in situ electrochemical deposition route, which significantly enhanced the diffusion ability of Zn2+ due to the synergistic effects of Zn2+ pillars and structural H2O. The resultant Zn-MnO2 based AZIBs delivers a record capacity of 696 mAh/g (0.5 mAh/cm2) based on the initial mass loading, which is approaching the theoretical capacity of MnO2 with a two-electrons reaction. In-situ Raman studies reveal highly reversible Zn2+ ions insertion/extraction behaviors and here the Zn-MnO2 plays the role of a container during the charge–discharge process. Further charge storage mechanism investigations point out the insertion/extraction of Zn2+ and H+ coincides, and such process is significantly facilitated results from superior interlayered configurations of Zn-MnO2. The excellent electrochemical performance of Zn-MnO2 achieved in this work suggests the deep ions pre-intercalation strategy may aid in the future development of advanced cathodes for AZIBs.

Facile deposition of carbon-doped TiO2 films by two-electrode electrodeposition setup

This study presents a simple electrochemical deposition route to obtain carbon-doped TiO2 films. The deposition of the films is carried out on silicon substrates from a mixture of methanol (CH3OH) and Titanium (IV) isopropoxide (Ti[OCH(CH3)2]4) solution using a simple two-electrode electrodeposition setup. The obtained films are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-Visible diffuse reflectance spectroscopy (DRS) and conductivity measurements. Depending on the deposition conditions, both amorphous and crystalline TiO2 films could be obtained. It is found that carbon is doped both substitutionally and interstitially. High carbon doping (up to 18.96%) enables to obtain TiO2 film with narrowed bandgap and high conductivity to about 2.3 eV and [Formula: see text] S cm[Formula: see text], respectively. This study suggests that the proposed electrodeposition route offers an easy way of obtaining conductive and narrowed bandgap TiO2 films on large surface areas.

Hybrid supercapacitors constructed from double-shelled cobalt-zinc sulfide/copper oxide nanoarrays and ferrous sulfide/graphene oxide nanostructures

Evolution of renewable energies in the era of the modernized world has been strongly tied up to the incessant development of high-performance energy storage systems benefiting from both high energy and power densities. In the present work, binder-free positive electrodes are fabricated via a facile electrochemical deposition route in which copper oxide nanorods (CuO NRs) directly grown onto the copper foam (CF) are decorated with bimetallic cobalt-zinc sulfide nanoarrays (Co-Zn-S NAs). The fabricated Co-Zn-S@CuO-CFs represent promising specific capacity of 317.03 C.g−1 at 1.76 A.g−1, along with superior cyclic stability (113% retention after 4500 cycles). Negative electrodes were further prepared through a direct deposition of iron sulfide nanosheets (Fe-S NSs) onto the graphene oxide (GO), showing remarkable the specific capacitance of 543.9 F.g−1 at 0.79 A.g−1. Receiving benefits from remarkable energy and power densities (25.71 Wh.kg−1 and 8.73 kW.kg−1) alongside the reasonable life-stability, the fabricated asymmetric supercapacitor (ASC) devices are on merit for developing high-performance energy storage systems.

Nucleation and growth kinetics of electrochemically deposited ceria nanostructures for high-temperature electrocatalysis

Cathodic electrochemical deposition, a simple and cost-effective route for fabricating ceria nanostructures, has attracted much attention in catalysis and renewable energy technologies. However, electrochemical nucleation and growth mechanisms that determine the nanoscale architecture of ceria films during deposition have not yet been clarified. In this study, we analyze current and mass-time transients and thin film microstructures as functions of applied potential and temperature. We then examine these results in light of analytical models for the determination of relative nucleation rate, nuclei density, and diffusivity of Ce ion during ceria electrocrystallization. As applied potential and temperature decrease, the reduced deposition rate allows nuclei to branch, leading to more ‘petal’-like nanostructures with high specific surface areas. These optimized ceria nanostructures greatly improve the hydrogen electro-oxidation rate and reduced electrode resistance when coated onto a model electrode that simulates a Ni/yttria-stabilized zirconia composite anode utilized in solid oxide fuel cells.

Electrochemical deposition synthesis of ZnO-NA/Cu2O-NPs type-II hierarchical heterojunction for enhanced photoelectrochemical degradation of methyl orange (MO)

Highly ordered ZnO nanorods array (ZnO-NA) films were fabricated on fluorine-doped tin oxide (FTO) substrates via a facilitate one-step electrochemical deposition route. Cu2O nanoparticles (Cu2O-NPs) films were then electrochemical deposited on the surface of ZnO-NA to constituted the ZnO-NA/Cu2O-NPs type-II hierarchical heterojunction. Steady-state photoluminescence (PL) spectra and nanosecond time-resolved transient photoluminescence (NTRT-PL) spectra of as-fabricated nanocomposites are studied, under light irradiation with wavelength of 266 nm. Simultaneously, a distinct 520 nm transient PL emission peak in the NTRT-PL spectra is observed owing to the presence of oxygen vacancy (OV) defect states, which is further convinced by the X-ray photoelectron spectroscopy (XPS). The PL decay spectroscopy confirms that ZnO-NA/Cu2O-NPs heterojunction could implement more facilitated avenue for transform and separation of photogenerated carriers associated with OV. Besides, the synthesized ZnO-NA/Cu2O-NPs nanocomposites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–vis spectrophotometer, Raman scattering spectra and linear sweep voltammogram (LSV) measurement, respectively. Our present research demonstrates a new approach to investigate charge separation and transport in a dual-band gap photoelectrochemical (PEC) system. Following this scheme, UV and visible-light photocatalytic activities of ZnO-NA/Cu2O-NPs heterojunction nanocomposites were evaluated through photodegradation of methyl orange (MO) in aqueous solution.

Delineating the role of surface characteristics on the solar selectivity of colored chromium oxide coating on 304 stainless steel substrate

Solar selective colored chromium oxide coatings were prepared on the SS304 substrate through the electrochemical deposition route to provide more options and flexibility in aesthetically design solar absorbers with acceptable energy performance. The variation of colors in the coatings was achieved by varying the coating thickness as a function of deposition time. Color changes in the coatings were also evident in the samples that were annealed under vacuum. Electron microscopic images show that nanometer sized pores are present on the coating surfaces. The pore-density, pore-size distribution and surface roughness exhibit significant changes with variations in deposition time and annealing temperature. Initially, the selectivity factor of 6.08 was recorded in the as prepared sample coated for 30 min, which improved to 7.36 on annealing the samples under vacuum at 700 °C, however, it drops to 4.22 when annealed at 900 °C. A similar trend was also observed for samples that are coated for 60 min. The results indicate that the pore-density, pore-size distribution and surface roughness play a dominant role in governing the solar selectivity of the coatings. Nanoindentation tests were performed on the coated samples and the results show that mechanical properties of the solar absorber coatings degrades with the increase in coating thickness but improve significantly with increase in annealing temperature.

Phase-controlled synthesis and the phase-dependent HER and OER performances of nickel selenide nanosheets prepared by an electrochemical deposition route

Phase-controlled synthesis of nickel selenide nanostructures was successfully realized via a facile electrodeposition route with the same electrolyte at room temperature.

Scalable one-step electrochemical deposition of nanoporous amorphous S-doped NiFe2O4/Ni3Fe composite films as highly efficient electrocatalysts for oxygen evolution with ultrahigh stability

Self-supported 3D nanoporous amorphous S-doped NiFe2O4/Ni3Fe composite films grown on nickel wire were fabricatedviaa facile and scalable one-step electrochemical deposition route in ethaline and developed as highly active and robustly stable electrocatalysts for OER in alkaline media.

New route of fabricating BiOI and Bi2O3 supported TiO2 nanotube arrays via the electrodeposition of bismuth nanoparticles for photocatalytic degradation of acid orange II

Well dispersed Bi nanostructures were synthesized on TiO2 nanotube arrays (TNAs) via a facile electrochemical deposition route at room temperature, employing Bi(NO3)3·5H2O as the reactant with the assistance of complexing agent and surfactant. The structures of the as-prepared product were characterized by scanning electron microscope, transmission electron microscope, X-ray diffraction and energy dispersive spectrometer. The influence of preparation conditions on Bi electrodeposition were investigated systematically. The results showed that the concentration of surfactant, the deposition voltage and pH value could markedly affect the morphology of Bi-TNAs. The prepared Bi-TNAs have been used to fabricate BiOI and Bi2O3 semiconductors supported on TNAs, which exhibited high visible-light photocatalytic efficiency for acid orange II degradation. This study predicates a promising path to synthesizing Bi-based photocatalysts on TNAs.

Nanostructured ZnO thin film with improved optical and electrochemical properties prepared by hydrothermal electrochemical deposition technique

Zinc oxide (ZnO) thin films were grown on fluorine-doped tin oxide coated glass substrate by the hydrothermal electrochemical deposition (HTED) route using slightly acidic aqueous zinc acetate solution at 80°C and were characterised by various techniques. The deposited films showed n-type behaviour with improved carrier concentration. The steady state photocurrent densities were found to be 0.4 mA/cm2 (under UV irradiation) and 8 µA/cm2 (under visible light illumination) at zero bias potential. Significant improvement of optical, electrochemical and photoelectrochemical properties of deposited films could be achieved using HTED technique.

Electrochemical deposition of silver on manganese dioxide coated reduced graphene oxide for enhanced oxygen reduction reaction

We have prepared a reduced graphene oxide (rGO)-supported silver (Ag) and manganese dioxide (MnO2) deposited porous-like catalyst (denoted as rGO/MnO2/Ag) through a facile electrochemical deposition route and have been used as a cathode catalyst for oxygen reduction reaction (ORR) in alkaline fuel cells. The physical properties of rGO/MnO2/Ag have been investigated via several instrumental methods. This material exhibits a polycrystalline structure characterized by Ag/MnO2 microsphere formation as a result of Ostwald ripening. The X-ray diffraction and X-ray photoelectron spectroscopy data reveal that the MnO2 and Ag have been slightly alloyed and Mn presents with the dioxide form on rGO. The electrochemical properties of the electrocatalyst have been studied via several voltammetric methods. The results demonstrated that the rGO/MnO2/Ag has an excellent catalytic activity for ORR in alkaline media compared to the other tested electrodes. Particularly, it shows 1.2 times higher current density and better electron transfer rate at 0.3 V per O2 than that of 20 wt% Pt/C. The other kinetic analysis reveals that the O2 has reduced directly to H2O through a nearly four-electron pathway with better anodic fuel tolerance and duration performance than that of 20% Pt/C.

Novel dye-sensitized solar cell architecture using TiO2-coated Ag nanowires array as photoanode

With the aim of reducing series resistance and increasing dye loading, novel dye-sensitized solar cell architecture was designed with TiO2 nanoparticle-coated Ag nanowires array as the photoanode. Ag nanowire array was prepared by anodic aluminum oxide (AAO) template-assisted electrochemical deposition route. Then, Ag nanowires were coated by TiO2 nanoparticles in hydrothermal process. The structures of the photoanode were characterized by field emission scanning electron microscopy (FESEM). Ag nanowires are covered by a layer of very fine nanoparticles with a diameter of less than 5 nm. X-ray diffraction (XRD) and selected-area electron diffraction (SAED) show that Ag nanowires have a strong preferred orientation in (220) direction and the TiO2 coating layer is a polycrystalline structure. With this photoanode, 3.2 % conversion efficiency is achieved for the cell sensitized with N3 dye.

NiMoO4@Co(OH)2 core/shell structure nanowire arrays supported on Ni foam for high-performance supercapacitors

NiMoO4@Co(OH)2 core/shell structure nanowire arrays (NWAs) supported on Ni foam were successfully fabricated via a facile hydrothermal growth and electrochemical deposition route, and applied in supercapacitors (SCs).

A simple and controlled electrochemical deposition route to urchin-like Pd nanoparticles with enhanced electrocatalytic properties

A simple, facile, green, and controlled one-step electrodeposition method was developed for preparation of well-defined urchin-like Pd nanoparticles on a glassy carbon electrode, using nitrite ions as the growth directing agent. No any organic solvent, template, surfactant, seed, or complex apparatus was involved. The as-prepared Pd nanostructures had “clean” surfaces because of the surfactant-free formation process. The obtained Pd deposits were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The experimental parameters including deposition potential, the dosage of H2PdCl4 and nitrite ions, and deposition time were investigated in details. The urchin-like Pd nanoparticles demonstrated better tolerance, enhanced electrocatalytic activity, and superior stability toward methanol oxidation in alkaline media.

Shape-controlled synthesis of copper telluride micro/nanostructures via a simple electrochemical deposition route

Shape-controllable synthesis of copper telluride micro/nanostructures has been successfully realized in air at room temperature by a simple galvanostatic electrodeposition route. By tuning experimental parameters such as the original Cu and Te sources, additives, deposition currents and media, copper telluride micro/nanostructures with various morphologies, including nanorod arrays, nanosphere-strewn copper telluride dendrites, copper telluride nanowires and star-like hexagonal copper telluride dendrites, were rapidly deposited in air at room temperature for 5 min. The final products were characterized by various means including X-ray diffraction, scanning electron microscopy, (high-resolution) transmission electron microscopy, and energy-dispersive spectrometry. The mechanisms of copper telluride production in various media are discussed.

Preparation and Characterization of CZTSe Films through Electrochemical Deposition Route

Preparation and Characterization of CZTSe Films through Electrochemical Deposition Route