•One-step synthesis of Au NPs and Au/PZrO2 NCPs has been developed.•Au particle size can be effectively controlled within a broad range from 5 to even 160 nm.•The new method can prevent the aggregation of Au NPs decorated on PZrO2 substrate.•Au/PZrO2 NCPs shows an improved sensitivity and stability of the SERS performance.One-step synthesis of gold (Au) nanoparticles (NPs) and Au/porous ZrO2 nanocomposites (Au/PZrO2 NCPs) have been developed using an ultra-low water content process. The reduction of HAuCl4 was accomplished in a sodium citrate sol (SCS) which had been prepared in anhydrous ethanol, instead of in water or in ethanol/water mixture. Then, highly uniform, well-distributed and size-controllable Au NPs and Au-based NCPs (Au/PZrO2) have been obtained using this SCS. The new method provides a simple and effective physical step that can control the Au particle size freely within a broad range from 5 to even 160 nm. The SCS can also greatly improve the dispersity of Au NPs situated on the ZrO2 substrate, which makes the hybrids (Au/PZrO2) achieving a very good stability and high sensitivity to organic molecule of 4-mercaptobenzoic acid (4-MBA). Furthermore, the new method requires no additional protectants or stabilizers and is capable to fabricate Au NPs with simultaneously good dispersity and small size even below 5 nm, which provides a promising avenue for preparing high quality of Au NPs and Au-based NCPs.Those organic solvents who have low-surface-tension but poor solubility towards sodium citrate are now turned round to be superiors in the synthesis of Au NPs and Au-based NCPs. The new method also provides a simple physical step that can effectively control Au NPs size, which makes the hybrids (Au/PZrO2) exhibiting novel optical properties.Download high-res image (332KB)Download full-size image

A novel two-step method is proposed to fabricate porous zirconia (ZrO2) thin films. A large-scale ZrO2 thin film is thus achieved, which displays a very good light transparency, as its total transmissivity is higher than 95% within the wavelength range of 450–1100 nm, a broad range just covering both the visible and near-infrared spectral range. This property makes it a promising candidate for solar cells as a high-temperature-resistant insulating layer.

•Advanced method for configuration classification of layers-composite is presented.•Graphene corrugation modulates the stacking arrangement of graphene and MoS2.•The bandgaps of all types graphene and MoS2 nanocomposite are opened.•All types graphene and MoS2 nanocomposites display an enhanced light absorption.The properties of graphene absorption on graphene-like material can be modulated by the stacking arrangement. Here, we propose a “least squares” classification method for analyzing configuration types of graphene/molybdenum disulfide heterobilayers (G/MoS2 HBLs) while binding energy, electronic structure and optical absorption of G/MoS2 HBLs are investigated via first principles calculations. Owing to the lattice mismatch, no traditional AA and AB stacking exist but AA- and AB-stacking-like configurations have been found. Paradoxically, AB-stacking-like configuration, generally as the most stable stacking sequence, does not correspond to the relaxed structure. We interpret this paradox in terms of graphene corrugation. A detailed analysis of the electronic structure indicates that bandgaps of all configurations types (types of G/MoS2 HBLs) are opened and tunable under the different interlayer distance. Furthermore, compared with monolayer MoS2, G/MoS2 HBLs display an enhanced light response, a promising feature for photocatalytic applications.

Butterfly wing skeleton is a widely used hard-template in recent years for fabricating photonic crystal structures. However, the smallest construction units for the most species of butterflies are commonly larger than ∼50 nm, which greatly hinders their applications in designing much smaller functional parts down to real “nano scale”. This work indicates, however, that hollow ZrO2 nanowires with ∼2.4 μm in length, ∼35 nm in diameter and ∼12 nm in wall thickness can be synthesized via the selection of suitable butterfly bio-templates followed by heat processing. Especially, the successful fabrication of these naturally cross-linked ZrO2 nanotubes suggests a new optional approach in fabricating assembled nano systems.Graphical abstractHighlights► Naturally cross-linked ZrO2 nanotubes with ∼2.4 μm in length, ∼35 nm in diameter and ∼12 nm in wall thickness was synthesized via the selection of suitable butterfly bio-templates followed by heat processing. ► The contractions, which are main defects of the former hard-template method based on butterflies, are well controlled with the help of the surface tension effect. ► The achieved hollow ZrO2 nanowires suggest a new optional approach that uses bio-templates in fabricating and designing nano systems.