Template-free Electrodeposition Research Articles

Nanoporous Ni current collectors with cone array supported Sn–Co alloys as anodes for high-performance lithium-ion batteries

Template-free electrodeposition creates nanoporous Sn–Co alloy electrodes, serving as binder-free anodes for lithium-ion batteries with enhanced lithium kinetics and stability.

Electrodeposition of One-Dimensional Nanostructures: Environmentally Friendly Method

During the past decade, nanotechnology has become an active field of research because of its huge potential for a variety of applications. When the size of many established, well-studied materials is reduced to the nanoscale, radically improved or new surprising properties often emerge. There are mainly four types of nanostructures: zero, one, two and three dimensional structures. Among them, one-dimensional (1D) nanostructures have been the focus of quite extensive studies worldwide, partially because of their unique physical and chemical properties. Compared to the other three dimensional structures, the first characteristic of 1D nanostructure is its smaller dimension structure and high aspect ratio, which could efficiently transport electrical carriers along one controllable direction; as a consequence they are highly suitable for moving charges in integrated nanoscale systems. The second characteristic of 1D nanostructure is its device function, which can be exploited as device elements in many kinds of nanodevices. Indeed it is important to note that superior physical properties including superconductivity, enhanced magnetic coercivity and the unusual magnetic state of some 1D nanostructures have been theoretically predicted and some of them have already been confirmed by experiments. In order to attain the potential offered by 1D nanostructures, one of the most important issues is how to synthesize 1D nanostructures in large quantities with a convenient method. Many synthetic strategies, such as solution or vapor-phase approaches, template-directed methods, electrospinning techniques, solvothermal syntheses, self-assembly methods, etc., have been developed to fabricate different classes of 1D nanostructured materials, including metals, semiconductors, functional oxides, structural ceramics, polymers and composites. All the methods can be divided into two categories: those carried out in a gas phase (i.e., “dry processes”) and those carried out in a liquid phase (i.e., “wet processes”). The dry processes include, for example, techniques such as chemical vapor deposition (CVD), physical vapor deposition (PVD), pulse laser deposition (PLD), metal-organic chemical vapor deposition (MOCVD), and molecular beam epitaxy (MBE). In general, these gas phase processes require expensive and specialized equipments. The wet processes include sol-gel method, hydrothermal method, chemical bath deposition (CBD) and electrodeposition. Among the above mentioned methods, electrodeposition has many advantages such as low cost, environmentally friendly, high growth rate at relatively low temperatures and easier control of shape and size. Generally, there are two strategies to produce the 1D nanostructures through the electrochemical process. They are the template-assisted electrodeposition, and the template-free electrodeposition. In this chapter, we will approach the recent progress and offer some prospects of future directions in electrodeposition of 1D nanostructures. Electrodeposition is a simple and flexible method for the synthesis of one-dimensional (1D) nanostructures and has attracted great attention in recent years.

Homogeneously distributed heterostructured interfaces in rice panicle-like SbBi-Bi2Se3-Sb2Se3 nanowalls for robust sodium storage

Antimony-based materials offer great potential for sodium-ion battery application owing to their high capacity and suitable Na alloying potential. However, their practical application is hampered by the rapid capacity decay resulting from serious volume change during cycling. Herein, we report a template-free electrodeposition method to grow SbBi-Bi2Se3-Sb2Se3 (SbBi-Se) self-supported nanowall array with a rice-panicle-like top surface directly on Cu substrates. During the electrodeposition, Bi, Sb, and Se have been simultaneously incorporated into the nanowalls, giving rise to an array structure with uniformly dispersed phases of SbBi alloy, and metal selenides Bi2Se3 and Sb2Se3. As a result, the heterostructured interfaces amongst these phases are also homogeneously distributed throughout the entire structure. The density functional theory calculation results indicate that these interfaces facilitate Na+ diffusion and promote electronic conduction, and the sample also demonstrates enhanced high-rate performance and superior cyclic retention with almost no capacity decay after 100 cycles at 0.7 A/g. More importantly, in-situ temperature sensing suggests that such a unique heterostructured material exhibits high thermal stability during charge/discharge, while ex-situ analysis confirms that this electrode material induces the formation of a highly stable SEI film, and verifies the high durability of these alloy and selenide phases allowing the interfaces to keep functioning during charge/discharge process.

Template-free electrodeposition of sponge-like porous polymer interwoven with the bi-metallic metal-organic framework and reduced graphene oxide and application in energy storage device

In this research, an effective template- and binder-free strategy was developed for the design and fabrication of hybrid-structure supercapacitor (HSSC) material based on the novel sponge-like porous polymer enclosed with the bi-metallic metal-organic framework (bi-MMOF) and reduced graphene oxide (RGO) films. For the implementation of this goal, the green, in-situ, and eco-friendly electrochemical deposition technique was employed to modification of the gold surface with the reduced graphene oxide (RGO), poly-dibenzoazepine (PDB) polymer, and Ni/Co bi-metallic metal-organic (bi-MMOF) films, respectively. This procedure was accomplished without the use of any binder, template, pretreatment, and chemical modification of the substrate in an aqueous solution and at room temperature. According to our hypothesis, the synergic effect of conductivity and electrochemical double-layer capacitance (EDLC) of reduced graphene oxide along with the conductivity and pseudocapacitive behaviour of water-stable Ni/Co bi-MMOF, and the high surface area of polymer can be provided enhanced supercapacitor features. The electrochemical surveys indicated the superior performance of the designed nanocomposite with a suitable specific capacitance of 686.0 F g−1 at 1.0 A g−1 and suitable rate performance 554.0 F g−1 at 8.0 A g−1. Also, the assembled symmetric hybrid-structure supercapacitor appeared suitable energy density of 8.4 Wh kg−1 at 200 W kg−1 power density and satisfied specific capacitance of 378.0 F g−1 at 0.5 A g−1 with extraordinary long-life stability (95.1 % capacity retention up to 5000 cycles). These outcomes illustrated the proposed procedure can be shed light on designing new Graphene-Polymer-MMOF configured supercapacitors.

On the prospects of magnetic-field-assisted electrodeposition of nano-structured ferromagnetic layers

Micro- and nano-structured ferromagnetic layers are attractive for super-hydrophobic and electrocatalytic applications and can be effectively synthesized using electrodeposition. Beside the use of capping agents, magnetic fields have recently been proven to promote the growth of mm-sized conical structures by alternatively generating a supportive local flow. Here we explore the prospects of using magnetic fields to support the growth of smaller, micro-/nano-sized conical structures. We first elaborate by numerical simulations how the local electrolyte flow and the related inhomogeneous mass transfer change with shrinking cone size. Related scaling laws are derived, and stronger viscous friction along with smaller concentration changes inside the diffusion layer are found to limit the support of the magnetic field. To enhance the structuring effect, pulsed electrodeposition and use of superconducting magnets are discussed. Second, systematic experiments on the template-free electrodeposition of nickel layers in magnetic fields of different orientations and intensities are performed. Regardless of the direction, strong fields are found to promote blunt-ended, shell-like structures. These results are finally discussed by the help of numerical simulations which additionally consider the global cell flow forced by the magnetic fields. Importantly, global flow is found to dominate compared to local flow. We therefore propose improved electrode geometries for future research to clarify the prospects of stronger magnetic fields.

An Effective Strategy for Template-Free Electrodeposition of Aluminum Nanowires with Highly Controllable Irregular Morphologies.

Aluminum nanowires with irregular morphologies were prepared by template-free electrodeposition from a room-temperature chloroaluminate ionic liquid. The effects of the diffusion condition and deposition potential on the morphologies of Al nanowires were investigated. The decrease of diffusion flux leads to the formation of particular segmented morphologies of Al nanowires. A dynamic equilibrium between the electrochemical reaction and the diffusion of Al2Cl7− results in the current fluctuation and the periodical variation of diameters in the Al nanowires growth period. Al nanowires with several kinds of morphologies can be controllably electrodeposited under a restricted diffusion condition, without using a template. Increasing the overpotential shows the similar influence on the morphology of Al nanowires as the decrease in diffusion flux under the restricted diffusion condition. Most of the segmented Al nanowires have a single crystalline structure and grow in the [100] orientation. This work also provides a new strategy for the fabrication of nanowires with highly controllable irregular morphologies.

Electrochemical construction of S-doped MnOx/Mn integrated film on carbon paper in a choline chloride based deep eutectic solvent for enhanced electrochemical water oxidation

The rational design and synthesis of highly efficient, precious metal-free electrocatalysts in the promotion of electrochemical water oxidation is essential for the sustainable use of renewable energy. Herein, an integrated, S-doped MnOx/Mn film developed on carbon paper (CP) formed by a two-step transformation approach that includes template-free electrodeposition and in-situ electrochemical oxidation is employed as an efficient oxygen evolution reaction (OER) electrocatalyst. The doping of S and in-situ electro-oxidation lead to a tailored electronic structure and phase composition, which endow the composite electrode with a significantly enhanced OER catalytic performance. This S-doped integrated electrode perfectly combines highly active MnOx outer layers with conductive metallic Mn inner layers to offer abundant catalytic interfaces and electronic paths, leading to favorable reaction kinetics. As a result, the optimal S-doped MnOx/Mn/CP offers a low overpotential of 435 mV at 10 mA cm−2 with a Tafel slope of 89.97 mV dec−1 as well as improved stability. Impressively, a highly intrinsic catalytic activity with a turnover frequency of 0.0112 s−1 is obtained for S-doped MnOx/Mn/CP, which is 4.2-fold higher than that of MnOx/Mn/CP. S doping plays a critical role in stabilizing the MnIIIOx active phase and is ultimately responsible for the enhanced catalytic performance. This work provides an integrated design concept and S doping approach suitable for boosting the OER catalytic performance of MnOx.

Microflow-Enhanced Bubble Dynamics Along With Gradient Porous Surfaces

Abstract Boiling heat transfer has been a popular topic for decades because of its ability to remove a significant amount of thermal energy while maintaining a low wall superheat during the liquid phase change. Such boiling mechanisms can be tailored by engineering new boiling substrates through surface wettability modification and/or microscale feature installation. Here, we create new types of heterogeneous boiling surfaces that integrate vertical gradient micropores on macroscale fins by using a template-free electrodeposition method. The gradient morphology and corresponding gradient wettability simultaneously enable bubble nucleation on the top pores and capillary wicking through the bottom pores. With these unique wetting characteristics, we find that the gradient pores installed at the trench bottom demonstrate the most significant boiling enhancement in critical heat flux and heat transfer coefficients by 160% and 600%, respectively. This enhancement can be attributed to the microflow-enhanced nature of bubble departures around the fins while isolating bubble nucleation and liquid supply through gradient pores. These results provide fundamental insights into boiling mechanisms using porous media and the potential for future works that can optimize the design of multidimensional heterogeneous surfaces to engineer flow patterns and boiling mechanisms accordingly.

Template-Free Preparation of Metal Nanowires by Two-Phase Electrolysis Using Cells Composed of Water and Oil Phases

Sn nanowires were prepared by template-free electrodeposition by two-phase electrolysis using a cell composed of water and oil phases. Prior to the electrodeposition, the water phase containing SnO4, NaCl, H2SO4, and C2H3N was mixed with the oil phase, methyl isobutyl ketone, to extract Sn species from the water phase to the oil phase. Sn nanowires were formed continuously on the surface of the electrode placed in the oil phase during electrodeposition. By using the water phase containing CuSO4, Cu nanowires were also obtained by two-phase electrolysis. The present process allows the high-throughput preparation of metal nanowires because the metal nanowires can be obtained continuously without the need for templates. The obtained metal nanowires are expected to be used in various applications, such as batteries, catalysts, and sensors.

Template-Free Electrochemical Deposition of t-Se Nano- and Sub-micro Structures With Controlled Morphology and Dimensions.

Selenium, depending on its crystal structure, can exhibit various properties and, as a result, be used in a wide range of applications. However, its exploitation has been limited due to the lack of understanding of its complex growth mechanism. In this work, template-free electrodeposition has been utilized for the first time to synthesize hexagonal-selenium (t-Se) microstructures of various morphologies at 80°C. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) revealed 5 reduction peaks, which were correlated with possible electrochemical or chemical reaction related to the formation of selenium. Potentiostatic electrodeposition using 100 mM SeO2 showed selenium nanorods formed at−0.389 V then increased in diameter up to −0.490 V, while more negative potentials (-0.594 V) induced formation of sub-micron wires with average diameter of 708 ± 116 nm. Submicron tubes of average diameter 744 ± 130 nm were deposited at −0.696 V. Finally, a mixture of tubes, wires, and particles was observed at more cathodic potential due to a combination of nucleation, growth, dissolution of structures as well as formation of amorphous selenium via comproportionation reaction. Texture coefficient as a function of applied potential described the preferred orientation of the sub-microstructures changed from (100) direction to more randomly oriented as more cathodic potentials were applied. Lower selenium precursor concentration lead to formation of nanowires only with smaller average diameters (124 ± 42 nm using 1 mM, 153 ± 46 nm using 10 mM SeO2 at −0.389 V). Time-dependent electrodeposition using 100 mM selenium precursor at −0.696 V explained selenium was formed first as amorphous, on top of which nucleation continued to form rods and wires, followed by preferential dissolution of the wire core to form tubes.

Template-free electrodeposition of ultra-high adhesive superhydrophobic Zn/Zn stearate coating with ordered hierarchical structure from deep eutectic solvent

The adhesion of superhydrophobic surface is closely correlated with its surface structures. As a new class of high-efficient green solvents, deep eutectic solvents are widely used to deposit superhydrophobic materials. However, there are still no reports of the electrodeposition of high-adhesive superhydrophobic materials from deep eutectic solvent. Herein, a simple method (free-template) is developed to fabricate an ordered hierarchical structured superhydrophobic Zn/Zn stearate coating with superior corrosion resistance from deep eutectic solvent. The Zn/Zn stearate-4 coating is composed of numerous orderly arranged pure Zn micro-slices and tens of thousands of Zn stearate nano-concaves. The unique structures show excellent superhydrophobic (164.8 ± 0.6°) and high adhesive performances due to the synergetic effect of strong capillary adsorption effect, large van der Waals' forces and quasi-continuous three-phase contact lines. The maximum value of water droplet that can be pinned on the overturned Zn/Zn stearate-4 surface is 30 μL. This work provides a new strategy to fabricate ultra-high adhesive superhydrophobic metal coating, which is promising for the application in microfluidic devices.

Binary MnO2/Co3O4 @ Well-aligned Electrospun Carbon Nanofibers for Sensitive, Nonenzymatic Glucose Sensing

A binary metal oxide composite, manganese oxide/cobalt oxide (MnO2 /Co3O4), on a well-aligned electrospun carbon nanofibers (MnO2/Co3O4@ECNFs) mat was synthesized via a simple one-step template-free electrodeposition process at a constant low-current (60 μA) for hours. The MnO2/Co3O4@ECNFs nanocomposite mat show excellent electrocatalytic activity towards sensitive and selective non-enzymatic glucose sensing. The MnO2/Co3O4@ECNFs nanocomposite were tested and characterized thoroughly by high resolution imaging and spectroscopic techniques. The results reveal that the binary metal oxides are uniformly deposited on the well-aligned ECNFs mat with high porosity, effective interconnectivity and large number of extended conducting channels. The electrochemical impedance spectroscopy (EIS) of the nanocomposite mat electrode show very good conductivity in 0.1 M KCl containing 5 mM [Fe(CN)6]3-/4-. The electrocatalytic activity of as-prepared MnO2/Co3O4@ECNFs for oxidation of glucose were performed by cyclic voltammetry (CV) and chronoamperometry (CA); and the experimental results demonstrate a superior sensing performance for glucose detection, including a rapid response (5 seconds), a wide dynamic range (up to 10.9 mM), excellent sensitivity of 973.91 μA mM-1 cm-2 and a detection limit of 0.02 μM (S/N=3) with satisfactory selectivity, reproducibility and stability. The plausible reactions involved for the electrocatalytic oxidation of glucose by the binary metal oxides are as follows.1 2Co02 + C6H1206 (glucose) -> 2Co00H + C6H1006 (gluconolactone) (1) 2Mn0 2 + C6H1206 (glucose) -> 2Mn00H + C6H1006 (gluconolactone) (2)Finally, the nanocomposite electrode was tested in glucose spiked human serum samples. The recovery rates of a series of standard glucose solutions are nearly 100%, suggesting the excellent performance and potential towards development of a nonenzymatic glucose biosensor for practical applications. Reference 1. Han, L.; Yang, D.-P.; Liu, A., Leaf-Templated Synthesis of 3d Hierarchical Porous Cobalt Oxide Nanostructure as Direct Electrochemical Biosensing Interface with Enhanced Electrocatalysis. Biosensors and Bioelectronics 2015, 63, 145-152.

Enhanced photoelectrochemical water splitting with template-free electrodeposition of SnS nanorods photoelectrode

In this paper, SnS nanorods were first prepared in an acidic solution by adjusting the amounts of tri-sodium citrate at room temperature using template-free electro-deposition method. The morphological characteristics and photoelectrochemical (PEC) properties of SnS nanorods thin films were investigated. The phase purity properties of deposited SnS thin films were analyzed by X-ray diffraction (XRD), energy disperse spectroscopy (EDS) and Raman spectra measurements. The morphological characteristics of SnS nanorods were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The band-gaps of SnS thin films were confirmed by UV–Vis–NIR diffuse reflectance spectrum. The PEC characterizations indicated that the photocurrent density of SnS nanorods thin films was about 46 μA/cm2 and the maximum IPCE value of SnS nanorods thin films was 9.3%. The fabrication of FTO/SnS (nanorods)/CdS/TiO2/Pt photoelectrode improved the PEC performances of SnS nanorods thin films greatly. The photocurrent density of FTO/SnS (nanorods)/CdS/TiO2/Pt reached 0.59 mA/cm2, and the maximum IPCE value of FTO/SnS (nanorods)/CdS/TiO2/Pt achieved 27.1%.

3D bimetallic Au/Pt nanoflowers decorated needle-type microelectrode for direct in situ monitoring of ATP secreted from living cells

Adenosine triphosphate (ATP) plays a crucial role in energy metabolism and extracellular purinergic signaling. A 3D bimetallic Au/Pt nanoflowers decorated ATP microelectrode biosensor prepared by facile and effective template-free electrodeposition was firstly reported, realizing local detection of cellular ATP secretion. The ATP biosensor was developed by co-immobilization of glucose oxidase and hexokinase, exhibiting long-term stability (79.39 ± 9.15% of its initial value remained after 14 days at 4 °C) and high selectivity with a limit of detection down to 2.5 μM (S/N = 3). The resulting ATP biosensor was then used for direct in situ monitoring of ATP secreted from living cells (PC12) with the stimulation of high K+ solutions. The obtained current was about 21.6 ± 3.4 nA (N = 6), corresponding to 12.2 ± 2.8 μM ATP released from cells, right in the micromolar range and consistent with the suggested levels. The 3D bimetallic Au/Pt nanoflowers possess excellent catalytic activity and large electroactive surface area, contributing to enzymatic activity preservation and long-term stability. This work provides a promising platform for long-time monitoring of other neurotransmitters and secretions in cellular glycolysis and apoptosis processes in the future.

High Stable Supercapacitors Based on Poly(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-yl)methanol Nanonet@Nanotube Array by Template-Free Electrochemical Preparation

Poly(3,4-ethylenedioxythiophene) and its derivatives provide an excellent platform as electrode materials for supercapacitors due to their superior stability and conductivity. In this study, a poly(2,3-dihydrothieno[3,4-b][1,4]dioxin-2-yl)methanol (PEDOT-MeOH) porous nanonet (PEDOT-MeOH-PNN), PEDOT-MeOH hollow nanotube array (PEDOT-MeOH-HNA) and PEDOT-MeOH-PNN coated PEDOT-MeOH-HNA (PEDOT-MeOH-PNN@PEDOT-MeOH-HNA) are successfully fabricated using a template-free electrodeposition of (2,3-dihydrothieno[3,4-b][1,4]dioxin-2-yl)methanol monomer. These three nanostructures were studied by Fourier transform infrared spectrum and Raman spectrum, scanning electron microscopy, thermal analysis and electrochemical methods, respectively. PEDOT-MeOH-PNN@PEDOT-MeOH-HNA has a specific capacitance of 40.5 mF cm−2 at 40 mV s−1, which is higher than PEDOT-MeOH-PNN (21.6 mF cm−2) and PEDOT-MeOH-HNA (35.5 mF cm−2). Moreover, the PEDOT-MeOH-PNN@PEDOT-MeOH-HNA based symmetric supercapacitor delivers excellent rate performance and superior cycling stability (90% of the initial capacitance remains after 10,000 cycles). The results indicate that the structural design of a supercapacitor electrode can improve their electrochemical performance, and promote the application and development of conducting polymers in the field of supercapacitors.

Template-free electrochemical synthesis of Cd/CdTe core/shell nanowires and CdTe nanotubes

Template-free electrodeposition was utilized to prepare Cd/CdTe nanowires and CdTe nanotubes for the first time, where the formation of one-dimensional structures was due to the highly anisotropic crystal structure and the Kirkendall effect.

Morphological and electronic modification of 3D porous nickel microsphere arrays by cobalt and sulfur dual synergistic modulation for overall water splitting electrolysis and supercapacitors

Herein, 3D hierarchically porous Co and S co-modificated nickel microsphere arrays developed on nickel foam (NF) substrate (NiCoxSy/NF) are synthesized via a facile template-free electrodeposition protocol in Ethaline-based deep eutectic solvent. The resultant NiCoxSy/NF at optimal incorporating level shows highly efficient electrochemical water splitting performance. The NiCoxSy/NF-based alkaline water electrolyzer requires small cell voltages of 1.57 and 1.63 V to reach 10 and 20 mA cm−2 overall current densities, sequentially, along with robust durability for over 100 h. Density function theory (DFT) study indicates that the synergistic actions induced by the dual-incorporation of Co and S, enabling to optimize the binding energies for water dissociation, hydrogen adsorption/desorption as well as the oxygen-containing intermediates. The NiCoxSy/NF manifests excellent electrocapacitive performance with high capacitance (4964 mF cm−2 at 5 mA cm−2) and well cycling stability (0.4% decay after 5000 cycles) being an electrode material for supercapacitor application. Particularly, an all-solid-state symmetric supercapacitor based on NiCoxSy/NF yields high energy density (48.46 Wh kg−1 at 500 W kg−1) with superior cycling durability (6.2% decay after 10,000 cycles). This study contributes a facile path for the synthesis of hierarchically porous materials and highlights the effect of multielement synergistic modulation to boost the electrochemical activity.

Electrodeposition of Platinum (Pt) Particles as a Catalyst of Hydrogenation of Acetone

Heterogeneous catalysts play an important role in accelerating chemical reactions in order to save energy and cost during the reaction process. Platinum (Pt) has received a great deal of attention for its application in many catalytic processes, but very few studies have evaluated it in the hydrogenation process of acetone. In this study, Pt particles were successfully grown on an indium tin oxide (ITO) coated glass substrate by means of a facile, one-step, and template-free electrodeposition method using a solution containing 2.0 mM H2PtCl6 and 0.5 M H2SO4 at room temperature. Potentiostatic and galvanostatic methods were employed to conduct the electrodeposition process under different potentials, current densities, and deposition times to observe their influence on the morphology of the electrodeposited Pt particles. It was found that the morphology of the particles could be facilely manipulated by adjusting the deposition current and potential by using the galvanostatic and potentiostatic methods, respectively. The potentiostatic method produced a spherical or bayberry-like shape whereas the galvanostatic method produced a flower-like shape. The sharp tips on the surface of the bayberry-like shape are electron-rich sites that can break the C = O bond in acetone, thereby forming C-OH bonds that can generate isopropanol molecules.

Template-free electrodeposition of SnS nanotubes and their photoelectrochemical properties

In this paper, SnS nanotubes are firstly prepared in acidic solution by template free electrodeposition method at room temperature. The morphological evolution and photoelectrochemical properties of SnS nanotubes are investigated. X-ray diffraction (XRD), energy dispersive X-ray spectrometry (EDS) and Raman spectra measurements examine the phase purities of deposited SnS thin films. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterizations indicate morphological properties of SnS nanotubes. The band-gap of SnS nanotubes is confirmed by UV–Vis-NIR diffuse reflection spectra. The photoelectrochemical measurements show that the photocurrent density of FTO/SnS nanotubes is about 31 μA/cm2 and maximum IPCE value of SnS nanotubes is 7.4%.

Template-free electro-synthesis of PbO2 nanorod with chrysanthemum-like array

PbO2 electrode is one of crucial materials in electrochemical field, however, the fabrications of nanostructured PbO2 materials are highly confined to the template method. In this work, the nanostructured PbO2 materials were controllably synthesized by template-free electrodeposition method. It is found that the microstructure of PbO2 material was highly depended on the electrochemical deposition models, i.e., cyclic voltammetry (CV) method, potentiostatic method (PM), pulse potentiostatic method (PPM) and pulse galvanostatic method (PGM). Especially, PbO2 nanorod built by nanoparticles with chrysanthemum-like array synthesized in the absence of template by pulse potential deposition method showed high specific capacitance and good stability for supercapacitor application.