Optimized Chemical Bath Deposition for Low Cost, Scalable, and Environmentally Sustainable Synthesis of Star-Like ZnO Nanostructures.

This paper highlights an affordable and straightforward method called chemical bath deposition (CBD) for generating different morphologies of ZnO-based nanostructures. In particular, a specific protocol was found to drive the growth versus a high-yield in-plane symmetric six-arm nanostructure, named a nanostar (NS). Each arm of the star consists of a cluster of parallel wires, creating a subnanostructure with a huge surface-to-volume ratio.

Nanocomposites based on CuO coated silver nanowire networks for high-performance oxygen evolution reaction.

The development of highly active, low-cost, and robust electrocatalysts for the oxygen evolution reaction (OER) is a crucial endeavor for the clean and economically viable production of hydrogen electrochemical water splitting. Herein, cuprous oxide (CuO) thin films are deposited on silver nanowire (AgNW) networks by atmospheric-pressure spatial atomic layer deposition (AP-SALD). AgNW@CuO nanocomposites supported on conductive copper electrodes exhibited superior OER activity as compared to bare copper substrate and bare AgNWs.

Pain-Free Alpha-Synuclein Detection by Low-Cost Hierarchical Nanowire Based Electrode.

Analytical methods for the early detection of the neurodegenerative biomarker for Parkinson's disease (PD), α-synuclein, are time-consuming and invasive, and require skilled personnel and sophisticated and expensive equipment. Thus, a pain-free, prompt and simple α-synuclein biosensor for detection in plasma is highly demanded. In this paper, an α-synuclein electrochemical biosensor based on hierarchical polyglutamic acid/ZnO nanowires decorated by gold nanoparticles, assembled as nanostars (NSs), for the determination of α-synuclein in human plasma is proposed.

Band Engineering versus Catalysis: Enhancing the Self-Propulsion of Light-Powered MXene-Derived Metal-TiO Micromotors To Degrade Polymer Chains.

Light-powered micro- and nanomotors based on photocatalytic semiconductors convert light into mechanical energy, allowing self-propulsion and various functions. Despite recent progress, the ongoing quest to enhance their speed remains crucial, as it holds the potential for further accelerating mass transfer-limited chemical reactions and physical processes. This study focuses on multilayered MXene-derived metal-TiO micromotors with different metal materials to investigate the impact of electronic properties of the metal-semiconductor junction, such as energy band bending and built-in electric field, on self-propulsion.

Low-Cost, High-Yield Zinc Oxide-Based Nanostars for Alkaline Overall Water Splitting.

The investigation of high-efficiency and sustainable electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media is critical for renewable energy technologies. Here, we report a low-cost and high-yield method to obtain ZnOHF-ZnO-based 2D nanostars (NSs) by means of chemical bath deposition (CBD). The obtained NSs, cast onto graphene paper substrates, were used as active materials for the development of a full water splitting cell.

Advances in WO-Based Supercapacitors: State-of-the-Art Research and Future Perspectives.

Electrochemical energy storage devices are one of the main protagonists in the ongoing technological advances in the energy field, whereby the development of efficient, sustainable, and durable storage systems aroused a great interest in the scientific community. Batteries, electrical double layer capacitors (EDLC), and pseudocapacitors are characterized in depth in the literature as the most powerful energy storage devices for practical applications. Pseudocapacitors bridge the gap between batteries and EDLCs, thus supplying both high energy and power densities, and transition metal oxide (TMO)-based nanostructures are used for their realization.

WO Nanorods Decorated with Very Small Amount of Pt for Effective Hydrogen Evolution Reaction.

The electrochemical hydrogen evolution reaction (HER) is one of the most promising green methods for the efficient production of renewable and sustainable H, for which platinum possesses the highest catalytic activity. Cost-effective alternatives can be obtained by reducing the Pt amount and still preserving its activity. The Pt nanoparticle decoration of suitable current collectors can be effectively realized by using transition metal oxide (TMO) nanostructures.

Enlightening the bimetallic effect of Au@Pd nanoparticles on Ni oxide nanostructures with enhanced catalytic activity.

Bimetallic decoration of semiconductor electrodes typically improves catalytic and sensing performances because of a well-claimed synergistic effect. A microscopic and quantitative investigation of such an effect on energy bands of semiconductor can be really useful for further exploitation. Au, Pd and Au@Pd (core@shell) nanoparticles (10-20 nm in size) were synthesized through chemical reduction method and characterized with scanning and transmission microscopy, Rutherford backscattering spectrometry, cyclic voltammetry electrochemical impedance spectroscopy and Mott-Schottky analysis.

Engineering of Nanostructured WO Powders for Asymmetric Supercapacitors.

Transition metal oxide nanostructures are promising materials for energy storage devices, exploiting electrochemical reactions at nanometer solid-liquid interface. Herein, WO nanorods and hierarchical urchin-like nanostructures were obtained by hydrothermal method and calcination processes. The morphology and crystal phase of WO nanostructures were investigated by scanning and transmission electron microscopy (SEM and TEM) and X-ray diffraction (XRD), while energy storage performances of WO nanostructures-based electrodes were evaluated by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) tests.

Optimization of Oxygen Evolution Reaction with Electroless Deposited Ni-P Catalytic Nanocoating.

The low efficiency of water electrolysis mostly arises from the thermodynamic uphill oxygen evolution reaction. The efficiency can be greatly improved by rationally designing low-cost and efficient oxygen evolution anode materials. Herein, we report the synthesis of Ni-P alloys adopting a facile electroless plating method under mild conditions on nickel substrates.

Localized Energy Band Bending in ZnO Nanorods Decorated with Au Nanoparticles.

Surface decoration by means of metal nanostructures is an effective way to locally modify the electronic properties of materials. The decoration of ZnO nanorods by means of Au nanoparticles was experimentally investigated and modelled in terms of energy band bending. ZnO nanorods were synthesized by chemical bath deposition.

Role of Substrate in Au Nanoparticle Decoration by Electroless Deposition.

Decoration of nanostructures is a promising way of improving performances of nanomaterials. In particular, decoration with Au nanoparticles is considerably efficient in sensing and catalysis applications. Here, the mechanism of decoration with Au nanoparticles by means of low-cost electroless deposition (ELD) is investigated on different substrates, demonstrating largely different outcomes.

Ultrasensitive Electrochemical Impedance Detection of DNA by Low-Cost and Disposable Au-Decorated NiO Nanowall Electrodes.

Nanostructured electrodes detecting bacteria or viruses through DNA hybridization represent a promising method, which may be useful in on-field applications where PCR-based methods are very expensive, time-consuming, and require trained personnel. Indeed, electrochemical sensors combine disposability, fast response, high sensitivity, and portability. Here, a low-cost and high-surface-area electrode, based on Au-decorated NiO nanowalls, demonstrates a highly sensitive PCR-free detection of a real sample of (Ma) DNA.

Disposable and Low-Cost Electrode Based on Graphene Paper-Nafion-Bi Nanostructures for Ultra-Trace Determination of Pb(II) and Cd(II).

There is a huge demand for rapid, reliable and low-cost methods for the analysis of heavy metals in drinking water, particularly in the range of sub-part per billion (ppb). In the present work, we describe the preparation, characterization and analytical performance of the disposable sensor to be employed in Square Wave Anodic Stripping Voltammetry (SWASV) for ultra-trace simultaneous determination of cadmium and lead. The electrode consists of graphene paper-perfluorosulfonic ionomer-bismuth nano-composite material.

Tailoring morphology to control defect structures in ZnO electrodes for high-performance supercapacitor devices.

Zinc oxide (ZnO) nanostructures were synthesized in the form of nanoparticles, nanoflowers and nanourchins. Structural, electronic and optical characterization of the samples was performed via standard techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence, Raman and ultraviolet-visible (UV-Vis) spectroscopy. Point defect structures which are specific to each morphology have been investigated in terms of their concentration and location via state-of-the-art electron paramagnetic resonance (EPR) spectroscopy.

New Synthetic Route for the Growth of α-FeOOH/NH-Mil-101 Films on Copper Foil for High Surface Area Electrodes.

A novel metal organic framework (MOF)-based composite was synthesized on a Cu substrate via a two-step route. An amorphous iron oxide/hydroxide layer was first deposited on a Cu foil through a sol-gel process; then, Fe-NH-Mil-101 was grown using both the iron oxide/hydroxide matrix, which provided the Fe centers needed for MOF formation, and 2-aminoterephthalic acid ethanol solution. This innovative synthetic strategy is a convenient approach to grow metal oxide/hydroxide and MOF composite films.

Ni(OH)@Ni core-shell nanochains as low-cost high-rate performance electrode for energy storage applications.

Energy storage performances of Ni-based electrodes rely mainly on the peculiar nanomaterial design. In this work, a novel and low-cost approach to fabricate a promising core-shell battery-like electrode is presented. Ni(OH)@Ni core-shell nanochains were obtained by an electrochemical oxidation of a 3D nanoporous Ni film grown by chemical bath deposition and thermal annealing.

Vapochromic and chemiresistive characteristics of a nanostructured molecular material composed of a zinc(ii)-salophen complex.

The vapochromic and chemiresistive properties of a nanofibrillar molecular material composed of an amphiphilic ZnII Schiff-base complex, 1, are explored with the aim to obtain new materials with multifunctional properties. The solid 1 is characterized by the existence of two stable dimorphs, both exhibiting a nanofibrillar morphology. The thermal annealing of the ground solid 1 induces an irreversible lamellar-to-square columnar structural phase transition, as assessed by differential scanning calorimetry and X-ray diffraction analysis.

Low-cost synthesis of pure ZnO nanowalls showing three-fold symmetry.

ZnO nanowalls (NWLs) represent a non-toxic, Earth abundant, high surface-to-volume ratio, semiconducting nanostructure which has already showed potential applications in biosensing, environmental monitoring and energy. Low-cost synthesis of these nanostructures is extremely appealing for large scale upgrading of laboratory results, and its implementation has to be tested at the nanoscale, at least in terms of chemical purity and crystallographic orientation. Here, we have produced pure and texturized ZnO NWLs by using chemical bath deposition (CBD) synthesis followed by a thermal treatment at 300 °C.

Performance of natural-dye-sensitized solar cells by ZnO nanorod and nanowall enhanced photoelectrodes.

In this work, two natural dyes extracted from henna and mallow plants with a maximum absorbance at 665 nm were studied and used as sensitizers in the fabrication of dye-sensitized solar cells (DSSCs). Fourier transform infrared (FTIR) spectra of the extract revealed the presence of anchoring groups and coloring constituents. Two different structures were prepared by chemical bath deposition (CBD) using zinc oxide (ZnO) layers to obtain ZnO nanowall (NW) or nanorod (NR) layers employed as a thin film at the photoanode side of the DSSC.

Flexible Organic/Inorganic Hybrid Field-Effect Transistors with High Performance and Operational Stability.

The production of high-quality semiconducting nanostructures with optimized electrical, optical, and electromechanical properties is important for the advancement of next-generation technologies. In this context, we herein report on highly obliquely aligned single-crystalline zinc oxide nanosheets (ZnO NSs) grown via the vapor-liquid-solid approach using r-plane (01-12) sapphire as the template surface. The high structural and optical quality of as-grown ZnO NSs has been confirmed using high-resolution transmission electron microscopy and temperature-dependent photoluminescence, respectively.