Short Nanorods Research Articles

Synthesis of Crystalline OMS‐2 with Urea Hydrogen Peroxide and its Application in Aerobic Oxidation Reactions

AbstractCryptomelane‐type manganese oxide (OMS‐2) was synthesized successfully using urea hydrogen peroxide (urea⋅H2O2) as the reductant in an acidic buffer solution. As‐prepared crystalline material was fully characterized by XRD, BET, XPS, SEM and HRTEM. The results demonstrate that OMS‐2 has nanofiber with short nanorod morphologies, very rich oxygen vacancy defects and more exposed crystal facets compared with ones synthesized with other H2O2‐containing reductants. These unique properties make nanostructural OMS‐2 an excellent heterogeneous catalyst in aerobic oxidation reactions, such as selective oxidation of mercaptan and oxygenation of alkylarenes.

Single Nanoparticle Electrochromism Reveals Heterogeneous Charge Storage Rates and Ion Trapping Sites in Pseudocapacitive Smart Windows

Developing large area electrochromic smart windows based on nanoscale materials demands that trillions of nanoparticles modulate between transparent and colored states at the same rate. However, it is unclear how nanoparticle heterogeneity contributes to variable coloration dynamics. Here we demonstrate a single nanoparticle electrochromism approach to study optical modulation rates upon lithiationof isolated, clustered, and thin film tungsten oxide nanorod electrodes. We observe a particle-dependent waiting time for coloration (from 100 ms to 10 s) due to Li-ion insertion at optically inactive surface sites. Longer nanorods achieve higher OD modulation than shorter nanorods because they develop a Li-ion gradient that increases from the nanorod ends to the middle. Interestingly, electrochromic irreversibility increases monotonically with the number of particle-particle interactions due to ion trapping at nanoparticle interfaces. These findings lead us to propose a nanostructured electrode architecture that optimizes coloration magnitude, rate, and reversibilityacross large area elecrochromic smart windows. Figure 1

In situ generated spinel-phase skin on layered Li-rich short nanorods as cathode materials for lithium-ion batteries

As main electrochemical power sources for portable electronic devices, lithium-ion batteries (LIBs) restricted by cathode materials should be further developed for the application in electric vehicles. Despite the restrictions of low Coulombic efficiency and serious voltage fading, high-capacity Li-rich layered oxides with high voltage are still attractive cathode materials for high-energy-density LIBs. Here, spinel-phase skin is in situ generated on Fe-containing Li-rich short nanorods by employing a direct hydrothermal method. The rational design of morphology and structure features is beneficial for the removal and embedding of lithium ions. Two-dimensional nanorod structure can greatly shorten the pathway length of Li-ion diffusion and electron transport, increase the interface area between the electrode and electrolyte, and provide more free space for Li-ion storage and transmission. Large porosity between short nanorods is conducive to the penetration and infiltration of the electrolyte. Moreover, the ultrathin spinel marginal nanolayer (~ 3 nm) can provide 3D diffusion channels for Li+ ions transportation due to its fast kinetics. Good electrochemical performances are exhibited by controlling the concentration of lithium source (LiOH·H2O). Owning to this unique structure and morphology design, the prepared compound delivers a high discharge specific capacity of 247.5 mAh g−1 at 20 mA g−1 and a good rate capability. The first Coulombic efficiency and voltage fading issue are also significantly improved. These Li-rich short nanorods with spinel-phase skin are considered promising as cathode materials for LIBs.

Investigation of the longitudinal magnetic field effect in SmBa2Cu3Oy films with various shaped artificial pinning centers

The longitudinal magnetic field (LMF) state, in which the magnetic field is applied parallel to the applied current direction and ab-plane of SmBa2Cu3Oy (Sm123) films with shaped artificial pinning centers (APCs) of various shapes is investigated. The in-field critical current density (Jc) of pure Sm123 films in the LMF state and films with Y2O3, Sm2BaCuO5, BaHfO3, and a multilayered structure with short BaHfO3 nanorods were measured in the configuration. The measurement revealed that there was significant Jc enhancement only in the multilayered film. From the viewpoint of flux pinning, 3D flux pinning is key to improving in-field Jc in the LMF state. However, the Sm123 films with APCs, such as Y2O3 and Sm2BaCuO5, did not have a larger Jc than the pure Sm123 films in the LMF state. This indicates that the APCs prevent the current flowing along the external magnetic field. Both of the 3D flux pinning and the pure layer in which current can flow without disturbance are important for the Jc enhancement in the LMF state.

Fano resonances in symmetric gold nanorod trimers

A symmetrical gold nanorod trimer structure consisting of a short center nanorod and two long nanorods on both sides is proposed. The scattering spectra, electromagnetic field and current density vector distributions across the central cross section of the nanorod trimer are calculated by the finite difference time domain method, and the effects of structural parameters and dielectric environment on Fano resonance characteristics are theoretically investigated in detail. The results show that the Fano resonance can be generated mainly due to the interference between the bonding electric dipole mode in lower energy and the antibonding electric dipole mode or antiphase magnetic dipole mode in higher energy. The Fano dip is blue-shifted with the decrease in the short nanorod length, the size of whole trimer structure with constant displacement, or the refractive index of dielectric medium in the gaps between the central nanorod and two side nanorods; the resonance intensity on both sides of the Fano dip also changes. Meanwhile, the bonding mode on the red side of the Fano dip is gradually dominated by the electric dipole mode of two side nanorods, and the spectral intensity increases, while the antibonding mode on the blue side gradually evolves into the short nanorod-dominated antiphase magnetic dipole mode, and the spectral intensity becomes weaker. The increase in the inter-rod spacing also leads the Fano dip to be blue-shifted, and a similar change in the spectral intensity occurs on both sides of the Fano dip, due to the degeneration of bonding and antibonding modes caused by the decrease of near-field coupling between the short nanorod and two side nanorods, which finally degenerate into the electric dipole modes generated by the short nanorod or the two side nanorods, respectively. In addition, the Fano dip is insensitive to the change of the side nanorod length, but the relative resonance intensity on both sides of the Fano dip also changes. Furthermore, it is found that the spectral contrast ratio of the Fano resonance first increases and then decreases by varying the above-mentioned structural parameters or dielectric environment. These results are expected to be used for guiding the design of Fano controllable nanostructures and also for developing the applications of specific micro-nano photonics.

Shape-controllable synthesis of GdVO4photocatalysts and their tunable properties in photocatalytic hydrogen generation

Novel visible light responsive materials for water splitting are essential for the efficient conversion of solar energy into hydrogen bond energy. Among other semiconductors, gadolinium orthovanadate has appropriate conduction and valence band edges positioned to split water molecules and a narrow band gap that allows the use of visible light for hydrogen generation. Thus, we present here that hydrogen evolution under visible light (λ > 420 nm) could be accomplished using hierarchical 3D GdVO4 particles, obtained by a simple, one pot hydrothermal synthesis. We found that applying various reaction components, such as EDTA-Na2 and EDTA, and adjusting the pH of the solution allow one to tune the shape of GdVO4 (such as short nanowires, long nanowires, short nanorods, long nanorods, nanoparticles and spheres - all having a tetragonal crystal structure) as well as optical and photocatalytic properties. The highest ability to photocatalytically split methanol solution into hydrogen under UV-Vis irradiation was detected for the long nanowire sample (42 μmol h-1), having almost 11 times higher efficiency in comparison with the weakest sample - short nanowires. In addition, GdVO4 spheres generated H2 more than 2 times (5.75 μmol h-1) in comparison with the short nanorod sample (2.5 μmol h-1) under visible light excitation. Photostable in three-hour work cycles, long nanowires and spheres were even able to generate hydrogen from pure water, reaching values of 17 and 3 μmol under UV-Vis and Vis light, respectively.

Length-Dependent Electronic Transport Properties of the ZnO Nanorod.

The two-probe device of nanorod-coupled gold electrodes is constructed based on the triangular zinc oxide (ZnO) nanorod. The length-dependent electronic transport properties of the ZnO nanorod was studied by density functional theory (DFT) with the non-equilibrium Green’s function (NEGF). Our results show that the current of devices decreases with increasing length of the ZnO nanorod at the same bias voltage. Metal-like behavior for the short nanorod was observed under small bias voltage due to the interface state between gold and the ZnO nanorod. However, the influence of the interface on the device was negligible under the condition that the length of the ZnO nanorod increases. Moreover, the rectification behavior was observed for the longer ZnO nanorod, which was analyzed from the transmission spectra and molecular-projected self-consistent Hamiltonian (MPSH) states. Our results indicate that the ZnO nanorod would have potential applications in electronic-integrated devices.

Folic Acid-Functionalized Gold Nanorods for Controlled Paclitaxel Delivery: In Vitro Evaluation and Cell Studies.

Short gold nanorods were synthesized (average length 28.08nm, average aspect ratio 3.54), which were functionalized with folic acid (FA) and 8-mercaptooctanoic acid (MOA) or 11-mercaptoundecanoic acid (MDA) and loaded with paclitaxel (PCT). FA was conjugated to the nanorods in order to render them targetable for cancer cells overexpressing folate receptors whereas MOA or MDA was attached on the nanorods in order to generate extra hydrophobic areas for entrapment of hydrophobic drugs such as PCT in the nanorods and in order to provide free carboxylic groups, which would allow for the conjugation of drug or other biofunctional molecules to the nanorods. The functionalized gold nanorods (GNRs-MOA-FA and GNRs-MDA-FA) did not exhibit any significant degree of aggregation in cell culture medium and blood plasma even after a prolonged incubation period of 7days, indicating the adequate colloidal stability of the nanorods in these media. The functionalized nanorods exhibited satisfactory entrapment efficiency (around 40%) for PCT and released less than 25% of their PCT content in phosphate buffer pH 7.4 in 48h. PCT entrapment efficiency was a little higher and PCT release rate a little lower in the GNRs-MOA-FA. Molecular analysis (qPCR) was used to find out that the MDA-MB-231 cancer cell line expresses the folate receptor (FL1R) whereas the MCF-7 cancer cell line does not. The PCT-loaded GNRs-MOA-FA were more cytotoxic than the PCT-loaded GNRs-MOA nanorods against the MDA-MB-231 cells, which probably relates to the higher uptake of the GNRs-MOA-FA nanorods by these cells. The opposite was true in the case of the MCF-7 cells.

Sulfidation of cobalt nickel oxide nanofibers for improving their specific capacity

An electrospinning method was used to synthesize the Co3O4/NiO nanofibers, which then was sulfurized by solvothermal method in order to improve their electrochemical properties. The SEM pictures showed that sulfurized Co3O4/NiO nanofibers were irregular short nano-rods consisting of nanocrystalline particles; the BET tests showed that sulfuration is beneficial to improve the specific surface area of the fibers; the XPS showed that the existence of the valence state: Co2+, Co3+, Ni2+, Ni3+ and S2− in sulfurized sample, which was confirmed by XRD as Co3S4 and Ni0.96S, respectively. Especially, electrochemical tests showed that the sulfurized Co3O4/NiO nanofibers electrode delivers high specific capacity of 156.84 mA h g−1 at 1 A g−1 and 151.07 mA h g−1 at 10 A g−1 and after 1000 cycles, its capacity retention reaches 87.3% at 5 A g−1. The mechanism of improving the electrochemical performance after sulfidation was also discussed in detail.

Dynamic Agitation‐Induced Centrifugal Purification of Nanowires Enabling Transparent Electrodes with 99.2% Transmittance

AbstractTo promote silver nanowire (AgNW) as a viable commercial alternative for transparent electrodes, it is necessary to further develop industrially scalable, high‐performance yielding and cost‐efficient methods of purifying large quantities of as‐prepared AgNW suspensions. In this work, a facile, effective, and mass scalable purification method that employs a novel dynamic agitation‐induced centrifugal filtration concept to obtain highly purified and printable AgNW solutions. This unique dynamic filtration system, which amalgamates the advantages of membrane filtration, centrifugal filtration and “cross‐flow” filtration, is effective at (1) removing nanoparticles, short nanorods and organic additives from as‐prepared AgNW suspensions without producing aggregation; (2) concentrating purified AgNW suspensions to a desirable concentration; and (3) formulating printable AgNW suspensions with suitable solvents. The resulting purified, polyol‐method synthesized AgNW with a modest aspect ratio of ≈1000 and narrowed length distribution, can be coated into flexible transparent electrodes to yield a transmittance of 99.2% and 95.2% at 230 and 29.6 ohm sq‐1 respectively. These performance metrics are comparable or exceed that of most transparent electrodes made from AgNW with larger aspect ratio (>2000) but purified through conventional purification methods. To maximize the dynamic purification efficiency, a model is also developed to describe and predict this dynamic filtration process.

Hydrothermal Synthesis and Phase Formation Mechanism of TiO<sub>2</sub>(B) Nanorods via Alkali Metal Titanate Phase Transformation

Titanium dioxide (B phase) with 1-D structures was successfully fabricated via a hydrothermal method with a subsequent ion-exchange process and calcination. P25, titanium isopropoxide (TTIP), rutile and also anatase were used as Ti precursors in the alkali hydrothermal system. TTIP promoted an elongation of nanorod morphology whereas the other precursors produced short nanorod structures. The different types of titanium precursors did not have any influence on the phase transformation during the fabrication process. Na2Ti6O13 was the primary intermediate product after washing the hydrothermal sample. H2Ti3O7 was the secondary intermediate phase obtained following proton-exchange of Na2Ti6O13 in HNO3 solution. Finally, the TiO2(B) phase was the product of calcination of the secondary intermediate product at 400°C for 5 hr. A phase transformation mechanism is presented based on an investigation of products at each of the steps. The effects of the synthesis conditions on tailoring of the crystal morphology are discussed. The growth direction of the TiO2(B) nanorods was investigated by HR-TEM and SADP. Finally, the metastable phase of TiO2(B) was shown to be transformed to anatase during thermal treatment at temperatures higher than 400°C.

Controlling Anisotropic Growth of Colloidal ZnSe Nanostructures.

Semiconductor nanocrystals serve as outstanding model systems for studying quantum confined size and shape effects. Shape control is an important knob for controlling their properties but so far it has been well developed mainly for heavy-metal containing semiconductor nanocrystals, limiting their further widespread utilization. Herein, we report a synthesis of heavy-metal free ZnSe nanocrystals with shape and size control through utilization of well-defined molecular clusters. In this approach, ZnSe nanowires are synthesized and their length and shape control is achieved by introduction of controlled amounts of molecular clusters. As a result of [Zn4(SPh)10](Me4N)2 clusters (Zn4 clusters) addition, short ZnSe nanorods or ZnSe nanodots can be obtained through tuning the ratio of Zn4 clusters to ZnSe. A study using transmission electron microscopy revealed the formation of a hybrid inorganic-organic nanowire, whereby the ligands form a template for self-assembly of ZnSe magic size clusters. The hybrid nanowire template becomes shorter and eventually disappears upon increasing amount of Zn4 clusters in the reaction. The generality of the method is demonstrated by using isostructural [Cu4(SPh)6](Me4N)2 clusters, which presented a new approach to Cu doped ZnSe nanocrystals and provided also a unique opportunity to employ X-ray absorption fine structure spectroscopy for deciphering the changes in the local atomic-scale environment of the clusters and explaining their role in the process of the nanorods formation. Overall, the introduction of molecular clusters presented here opens a path for growth of colloidal semiconductor nanorods, expanding the palette of materials selection with obvious implications for optoelectronic and biomedical applications.

Vertical Alignment of Size-Controlled Self-Assembled Diphenylalanine Peptide Nanotubes Using Polyethersulfone Hollow Fiber Membranes On Silicon

The strong piezoelectricity in diphenylalanine peptide develops its technological potential as a smart material. To achieve insight into the vertical alignment of size-controlled self-assembled diphenylalanine peptide nanotubes, an aromatic peptide of diphenylalanine (FF) was applied in this research as the model peptide. Here we found for the first time a vertical alignment of size-controlled self-assembled diphenylalanine peptide nanotubes during the peptide self-assembly process of nanotubes composite using polyethersulfone (PES) membrane in situ and ex situ peregnation of peptide nano tube. The membrane structure was investigated using fluofenamic acid as a fluorescent tag and a first-line solution containing dipeptides and hexafluoropropane (HFP). The results showed a vertical alignment of size-controlled self-assembled diphenylalanine peptide nanotubes formation on silicon. The STM and SEM results indicated the formation of different nanostructures including short nanorods, nanotubes branched nanotubes and dendritic nanostructures of peptide in PES membrane. Our novel approach based on the PES membrane and HFP allows one to controllably fabricate various peptide-based nanostructures on silicon.

In Situ Vaccination with Cowpea vs Tobacco Mosaic Virus against Melanoma.

Cancer immunotherapy approaches have emerged as novel treatment regimens against cancer. A particularly interesting avenue is the concept of in situ vaccination, where immunostimulatory agents are introduced into an identified tumor to overcome local immunosuppression and, if successful, mount systemic antitumor immunity. We had previously shown that nanoparticles from cowpea mosaic virus (CPMV) are highly potent in inducing long-lasting antitumor immunity when used as an in situ vaccine in various tumor mouse models. Here we asked whether the nanoparticles from tobacco mosaic virus (TMV) could also be applied as an in situ vaccine and, if so, whether efficacy or mechanism of immune-activation would be affected by the nanoparticle size (300 × 18 nm native TMV vs 50 × 18 nm short TMV nanorods), shape (nanorods vs spherical TMV, termed SNP), or state of assembly (assembled TMV rod vs free coat protein, CP). Our studies indicate that CPMV, but less so TMV, elicits potent antitumor immunity after intratumoral treatment of dermal melanoma (B16F10 using C57BL/6 mice). TMV and TMVshort slowed tumor growth and increased survival time, however, at significantly lower potency compared to that of CPMV. There were no apparent differences between TMV, TMVshort, or the SNP indicating that the aspect ratio does not necessarily play a role in plant viral in situ vaccines. The free CPs did not elicit an antitumor response or immunostimulation, which may indicate that a multivalent assembly is required to trigger an innate immune recognition and activation. Differential potency of CPMV vs TMV can be explained with differences in immune-activation: data indicate that CPMV stimulates an antitumor response through recruitment of monocytes into the tumor microenvironment (TME), establishing signaling through the IFN-γ pathway, which also leads to recruitment of tumor-infiltrated neutrophils (TINs) and natural killer (NK) cells. Furthermore, the priming of the innate immune system also mounts an adaptive response with CD4+ and CD8+ T cell recruitment and establishment of effector memory cells. While the TMV treatment also lead to the recruitment of innate immune cells as well as T cells (although to a lesser degree), key differences were noted in cyto/chemokine profiling with TMV inducing a potent immune response early on characterized by strong pro-inflammatory cytokines, primarily IL-6. Together, data indicate that some plant viral nanotechnology platforms are more suitable for application as in situ vaccines than others; understanding the intricate differences and underlying mechanism of immune-activation may set the stage for clinical development of these technologies.

Improving the electrochemical performance of Nano-PANI by adding manganese

In order to improve the electrochemical performance of PANI, we prepared Mn2+ or Mn2O3 doped PANI nanomaterial by interfacial polymerization or in situ polymerization method. The SEM pictures showed that all samples were irregular short nano-rods; the FT-IR and XPS detected the quinone ring and benzene ring information in PANI and especially the XPS showed that manganese existed in the form of Mn2O3 in a sample; the BET tests showed that the Mn doping is beneficial to increase the specific surface area of the doped sample. The electrochemical property of all samples was studied by a three-electrode system in 0.5 mol/L H2SO4. It was found that at the current density of 1 A/g, the maximum specific capacitance of pure PANI was only 378 F/g, which was obviously lower than that of doped samples. Among the doped samples, Mn2O3/PANI had the best performance. Its specific capacitance was 719 F/g, and its capacitance retention was over 90% after 2000 charge–discharge cycles at 10 A/g. Afterwards, the mechanism of improving the electrochemical behavior of nano-PANI by adding manganese was also discussed.

PVP-assisted hydrothermal synthesis of VO(OH)2 nanorods for supercapacitor electrode with excellent pseudocapacitance

Vanadium oxyhydroxide VO(OH)2, which may possess specific chemical and physical properties, has been paid less attention comparing with vanadium oxides. Herein, with the assistance of polyvinyl pyrrolidone (PVP) and by adjusting pH about 4.7, VO(OH)2 was successfully synthesized by a facile hydrothermal method for the first time, which were short nanorods with widths of 50–130 nm and lengths of 250–500 nm. Electrochemical performance of VO(OH)2 nanorods was firstly investigated as supercapacitor electrodes, which were studied by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). VO(OH)2 nanorods showed capacitive behavior based on pseudocapacitance and superior rate capability. Specific capacitance of 198 F·g−1 was achieved at 0.5 A·g−1. These findings suggested that VO(OH)2 nanorods can be promising candidate as potential material for supercapacitor electrode.

End-to-end and side-by-side alignment of short octahedral molecular sieve (OMS-2) nanorods into long microyarn superarchitectures and highly flexible membranes

Porous and highly flexible OMS-2 membranes have successfully been obtained via side-by-side and end-to-end alignment of the short OMS-2 nanorods into 1D microyarn superarchitectures and interweaving the resultant microyarn superarchitectures under ambient pressure. The side-by-side and end-to-end alignment of the short OMS-2 nanorods into 1D microyarn superarchitectures is effected by the use of cheap, abundant, and bioavailable cellulose linters as a sacrificial template that is completely digested within the course of the reaction and thus no post-synthesis treatment to remove it is required. The as-prepared OMS-2 membrane, without the use of conductive carbon, shows specific capacitance of 104 F/g at current density of 0.5 A/g and excellent electrochemical cycling. Scanning and transmission electron microscopy reveals the remarkable alignment of the short nanorods into microyarn superarchitectures and interweaving of the microyarns. In addition, transmission electron microscopy shows that the primary building blocks, the nanorods, are singly crystalline while cross-sectional imaging by tomography shows stratified and porous internal structure of the membrane.

Surface modification of ZnO nanostructured film prepared by hot water oxidation

ZnO nanostructured films with tunable morphology were fabricated using hot water oxidation of etched Zn foils at 90 °C under varying solution conditions. At high pH, coarse ZnO nanostructured film, consisting of short nanorods, was produced. When the pH was lowered to about 3.8, no ZnO nanostructures were produced. On the other hand, a 1D-2D composite ZnO nanostructured film, consisting of nanorods and nanosheets, was formed by adding 0.05 to 0.20 M ZnCl2 during hot water oxidation. Increasing the ZnCl2 concentration further produced simonkolleite platelets instead of ZnO. The as-synthesized ZnO nanostructured films showed excellent wettability with static water contact angle ranging from 0 to 22.37°. Surface modification with stearic acid and 1-hexadecene under UV illumination effectively altered the wetting properties of the ZnO nanostructured films, resulting to superhydrophobic surfaces with static water contact angles of 149.90–156.62° and contact angle hysteresis as low as 1.63°. The 1-hexadecene-treated pencil-like ZnO nanorods achieved the highest water contact angle and retained its superhydrophobicity even after mechanical abrasion.

Preparation of Nano-Co3O4 by Direct Thermal Decomposition of Cobalt(II) Nitrate Hexahydrate for Electrochemical Water Oxidation

Background: Nano-Co3O4 has been used in various technological areas and applications such as electrochemical sensors and electrochemical water splitting. Even though many efforts have been expended to prepare nano-Co3O4, the development of novel methods to prepare Co3O4 using simple processes and at low cost remain a topic of interest. Besides, it could be economic and useful if the synthesized nanoparticle could be applied as efficient electrocatalyst upon its immobilization on a cheap base electrode material by very simple method for various practical applications including renewable energy. Method: We prepared nano-Co3O4 by a direct thermal decomposition of an inexpensive, simple and widely available cobalt inorganic precursor, such as Co(NO3)2·6H2O without any type of prereaction or processing. The nano-Co3O4 was immobilized on filter-paper-derived carbon electrode by drop-drying method for applying as electrode materials toward water electrooxidation. Results: The X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy analysis confirmed the formation of short nanorods of single-phase Co3O4 upon thermal decomposition of Co(NO3)2·6H2O at 520°C. The electrocatalytic properties of the nano- Co3O4 were evaluated after immobilizing it on a cheap carbon electrode derived from normal filter paper. The modified electrode showed good electrocatalytic properties toward water oxidation in an alkaline solution. Conclusion: In conclusion, we developed a very simple, straight-forward and economic method for preparation of nano-Co3O4 and immobilized it on very cheap carbon electrode for evaluating its electrocatalytic properties. Due to the high electrocatalytic properties, the prepared nano-Co3O4 could potentially play an important role in various practical fields.

Adjusting the Anisotropy of 1D Sb2Se3 Nanostructures for Highly Efficient Photoelectrochemical Water Splitting

AbstractSb2Se3 has recently spurred great interest as a promising light‐absorbing material for solar energy conversion. Sb2Se3 consists of 1D covalently linked nanoribbons stacked via van der Waals forces and its properties strongly depend on the crystallographic orientation. However, strategies for adjusting the anisotropy of 1D Sb2Se3 nanostructures are rarely investigated. Here, a novel approach is presented to fabricate 1D Sb2Se3 nanostructure arrays with different aspect ratios on conductive substrates by simply spin‐coating Sb‐Se solutions with different molar ratios of thioglycolic acid and ethanolamine. A relatively small proportion of thioglycolic acid induces the growth of short Sb2Se3 nanorod arrays with preferred orientation, leading to fast carrier transport and enhanced photocurrent. After the deposition of TiO2 and Pt, an appropriately oriented Sb2Se3 nanostructure array exhibits a significantly enhanced photoelectrochemical performance; the photocurrent reaches 12.5 mA cm−2 at 0 V versus reversible hydrogen electrode under air mass 1.5 global illumination.