Efficient Carrier Transport in 2D BiOSe/CsBiI Perovskite Heterojunction Enables Highly-Sensitive Broadband Photodetection.

2D BiOSe has recently garnered significant attention in the electronics and optoelectronics fields due to its remarkable photosensitivity, broad spectral absorption, and excellent long-term environmental stability. However, the development of integrated BiOSe photodetector with high performance and low-power consumption is limited by material synthesis method and the inherent high carrier concentration of BiOSe. Here, a type-I heterojunction is presented, comprising 2D BiOSe and lead-free bismuth perovskite CsBiI, for fast response and broadband detection.

Controlled Growth of Large-Sized and Phase-Selectivity 2D GaTe Crystals.

GaTe has recently attracted significant interest due to its direct bandgap and unique phase structure, which makes it a good candidate for optoelectronics. However, the controllable growth of large-sized monolayer and few-layer GaTe with tunable phase structures remains a great challenge. Here the controlled growth of large-sized GaTe with high quality, chemical uniformity, and good reproducibility is achieved through liquid-metal-assisted chemical vapor deposition method.

Self-templated formation of (NiCo)S yolk-shelled spheres for high-performance hybrid supercapacitors.

Rational materials design for the synthesis of desirable hollow micro- and nanostructures has recently revealed the remarkable potential for high-performance energy storage and conversion devices. Owing to their unique "core-void-shell" structural configurations, yolk-shell-structured electrode materials can achieve intimate contact with the electrolyte and alleviate the volume expansion issue during electrochemical cycling, which is therefore poised to further boost the electrochemical properties of hybrid supercapacitors. Herein, a facile self-templated strategy, consisting of a hydrothermal step and a high-temperature sulfurization process, has been developed for the construction of yolk-shell (NiCo)9S8 spheres in situ coated by graphite carbon ((NiCo)9S8/GC) due to the non-equilibrium thermal treatment of alkali metal alkoxides.

High-performance mesoporous γ-FeO sphere/graphene aerogel composites towards enhanced lithium storage.

Transition metal oxides have recently been demonstrated as highly attractive anodes for high-capacity lithium ion batteries, whose electrochemical properties could be further improved through rational architecture design and incorporating reliable conductive network. Herein, mesoporous γ-FeO spheres/graphene aerogel composites were synthesized via a solvothermal pathway followed by suitable annealing. Experimental results reveal the uniform mesoporous structure and well-dispersed γ-FeO spheres with the size of 300-400 nm embedded in the mesopores of the graphene aerogel network.

Selenium-rich nickel cobalt bimetallic selenides with core-shell architecture enable superior hybrid energy storage devices.

The continuous exploration of advanced electrode materials is of remarkable significance to revolutionize next-generation high-performance energy storage devices towards a green future. Benefiting from their electrochemically active sites and abundant redox centers, bimetallic selenides with desirable nanostructures recently have emerged as promising electrode alternatives for battery-supercapacitor hybrid (BSH) devices which demonstrate enormous potential in bridging the gap between electrochemical properties with high power densities (supercapacitors) and energy densities (batteries). Herein, employing the hydrothermal approach with solid Ni-Co spheres as precursors followed by the selenization process, selenide-rich bimetallic selenide spheres with a core-shell nanostructure were rationally designed and synthesized for use as the cathode electrode in superior BSH devices.

Achieving Ultrahigh Capacity with Self-Assembled Ni(OH) Nanosheet-Decorated Hierarchical Flower-like MnCoO Nanoneedles as Advanced Electrodes of Battery-Supercapacitor Hybrid Devices.

Self-assembled Ni(OH) nanosheet-decorated hierarchical flower-like MnCoO nanoneedles were synthesized via a cost-effective and facile hydrothermal strategy, aiming to realize a high-capacity advanced electrode of a battery-supercapacitor hybrid (BSH) device. It is demonstrated that the as-synthesized hierarchical flower-like MnCoO@Ni(OH)-nanosheet electrode exhibits a high specific capacity of 318 mAh g at a current density of 3 A g and still maintains a capacity of 263.5 mAh g at a higher current density of 20 A g, with an extremely long cycle lifespan of 87.

Enhanced Transmission and Self-Cleaning of Patterned Sapphire Substrates Prepared by Wet Chemical Etching Using Silica Masks.

Highly transparent and superhydrophilic sapphire with surface antireflective subwavelength structures were prepared by wet etching using colloidal monolayer silica masks. The film thicknesses of the silica masks were adjusted by the volume concentrations of polystyrene spheres. The evolution of etching morphologies of sapphire was studied, and antireflective concave pyramid nanoarrays on sapphire substrates were designed by calculation and were then prepared.

Broad-band anti-reflective pore-like sub-wavelength surface nanostructures on sapphire for optical windows.

Compared with conventional anti-reflective film, an anti-reflective sub-wavelength surface structure provides an ideal choice for a sapphire optical window especially in harsh environments. However, it is still a challenge to obtain a sapphire anti-reflective surface microstructure because of its high hardness and chemical inertness. In this paper, combined with optical simulation, we proposed a facile method based on the anodic oxidation of aluminum film and following epitaxial annealing.

Helical growth of aluminum nitride: new insights into its growth habit from nanostructures to single crystals.

By understanding the growth mechanism of nanomaterials, the morphological features of nanostructures can be rationally controlled, thereby achieving the desired physical properties for specific applications. Herein, the growth habits of aluminum nitride (AlN) nanostructures and single crystals synthesized by an ultrahigh-temperature, catalyst-free, physical vapor transport process were investigated by transmission electron microscopy. The detailed structural characterizations strongly suggested that the growth of AlN nanostructures including AlN nanowires and nanohelixes follow a sequential and periodic rotation in the growth direction, which is independent of the size and shape of the material.

Large-scale fabrication of nanopatterned sapphire substrates by annealing of patterned Al thin films by soft UV-nanoimprint lithography.

Large-scale nanopatterned sapphire substrates were fabricated by annealing of patterned Al thin films. Patterned Al thin films were obtained by soft UV-nanoimprint lithography and reactive ion etching. The soft mold with 550-nm-wide lines separated by 250-nm space was composed of the toluene-diluted polydimethylsiloxane (PDMS) layer supported by the soft PDMS.

[Effect of technological parameters of sputtering on the microstructure of silicon film investigated by Raman analysis].

In order to facilitate optical polishing of silicon carbide space telescope, in the present paper, silicon film, which has similar coefficient of thermal expansion with silicon carbide, was fabricated on SiC substrate by radio frequency magnetron sputtering. The effect of substrate temperature, radio frequency power, and substrate bias voltage was investigated by Raman scattering. The results indicate that at lower substrate temperature, the crystalline volume fraction of Si films increases with the increase in deposition temperature.

Neutron irradiation and post annealing effect on sapphire by positron annihilation.

Sapphire single crystals grown by an improved Kyropoulos-like method are irradiated by fast neutron flux. The irradiated doses of neutron are 10(18) and 10(19)n/cm(2). The infrared transmission spectra of sapphire were studied before and after irradiation.

[XPS and Raman spectral analysis of nitrogenated tetrahedral amorphous carbon (ta-C : N) films with different nitrogen content].

Nitrogenated tetrahedral amorphous carbon (ta-C : N) films were prepared on the polished C--Si substrates by introducing highly pure nitrogen gas into the cathode region and the depositing chamber synchronously using filtered cathodic vacuum arc (FCVA) technology. The nitrogen content in the films was controlled by changing the flow rate of nitrogen gas. The configuration of ta-C : N films was investigated by means of X-ray photoelectron spectroscopy (XPS) and visible Raman spectroscopy.

[Spectroscopic ellipsometry investigations of amorphous diamond films deposited with filtered arc].

In order to investigate thoroughly the optical properties of amorphous diamond (alpha-D) films deposited by the filtered vacuum arc technology, the optical constants of the films were measured by spectroscopic ellipsometry. Moreover, the dispersion relations of the optical constants, and the correlations among refractive index, extinction coefficient, optical gap and the substrate bias were also analyzed. It has been shown that the refractive index of alpha-D films is higher than that of diamond crystal, and the absorption edge corresponding to the interband transformation can be described with the parabolic line shape.