Branched HgTe Nanorods for Stable Room Temperature Extended Short-Wave Infrared Photodetectors.

Single-element detectors (SEDs) with a room temperature extended short-wave infrared (eSWIR) photoresponse were fabricated with branched nanorods of HgTe. Nanorods with high aspect (length/width) ratios were obtained by using stoichiometric excesses of Hg (i.e.

Highly efficient carrier multiplication in inverted CdSe/HgSe quantum dots mediated by magnetic impurities.

Incorporating manganese (Mn) impurities into II-VI semiconductors alters their properties through strong exchange interactions with the host material. In colloidal quantum dots (QDs), these interactions enable ultrafast bidirectional energy transfer between the magnetic impurity and the QD intrinsic states, with rates exceeding the rate of energy loss via phonon emission. This suggests that Mn-QD interactions could harness hot carrier energy before dissipation.

Colloidal Germanium Quantum Dots with Broadly Tunable Size and Light Emission.

Germanium (Ge) colloidal quantum dots (CQDs) were synthesized by thermal decomposition of GeI using capping ligand mixtures of oleylamine (OAm), octadecene (ODE), and trioctylphosphine (TOP). Average diameters could be tuned across a wide range, from 3 to 18 nm, by adjusting reactant concentrations, heating rates, and reaction temperatures. OAm promotes decomposition of GeI to Ge and serves as a weakly bound capping ligand.

Colloidal quantum dots enable tunable liquid-state lasers.

Present-day liquid-state lasers are based on organic dyes. Here we demonstrate an alternative class of liquid lasers that use solutions of colloidal quantum dots (QDs). Previous efforts to realize such devices have been hampered by the fast non-radiative Auger recombination of multicarrier states required for optical gain.

Designing a highly near infrared-reflective black nanoparticles for autonomous driving based on the refractive index and principle.

Hypothesis: The development of highly NIR reflective black single-shell hollow nanoparticles (BSS-HNPs) can overcome the Light Detection and Ranging (LiDAR) sensor limitations of dark-tone materials. The crystalline phase of TiO and the refractive index can be controlled by calcination temperature. The formation of hollow structure and the refractive index is expected to simultaneously increase the light reflection and LiDAR detectability.

Designing Novel LiDAR-Detectable Plate-Type Materials: Synthesis, Chemistry, and Practical Application for Autonomous Working Environment.

Plate-type hollow black TiO (HL/BT) with a high NIR reflectance was fabricated for the first time as a LiDAR-detectable black material. A TiO layer was formed on commercial-grade glass by using the sol-gel method to obtain a plate-type structure. The glass template was then etched with hydrofluoric acid to form a hollow structure, and blackness was further achieved through NaBH reduction, which altered the oxidation state of TiO to black TiO or Ti to Ti and Ti.

Vivid-Colored Electrorheological fluids with simultaneous enhancements in color clarity and Electro-Responsivity.

Hypothesis: Surface modification of dielectric materials changes the dipole-dipole interactions under electric fields, thereby controlling the electrorheological (ER) response. The introduction of metal oxides onto mica templates and further coating of dyes is expected to simultaneously improve the color clarity and ER performance.

Experiments: Dye-coated TiO platelets on mica are synthesized for high-performance colorful ER fluids.

A Study on Enhanced Electrorheological Performance of Plate-like Materials via Percolation Gel-like Effect.

The use of plate-like materials to induce a percolation gel-like effect in electrorheological (ER) fluids is sparsely documented. Hence, we dispersed plate-like materials, namely natural mica, synthetic mica, and glass, as well as their pulverized particles, in various concentrations in silicone oil to form ER fluids. Subsequently, the rheological properties of the fluids were evaluated and compared to identify the threshold concentration for percolating a gel-like state.

Preparation of a High-Performance Asymmetric Supercapacitor by Recycling Aluminum Paper and Filter Components of Heated Tobacco.

In this study, Al paper and cellulose acetate (CA) filters derived from heated tobacco waste were successfully converted into current collectors and active materials for a supercapacitor device. Typically, heated tobacco contains electrically discontinuous Al paper. First, Al was extracted from the tobacco waste using HCl to produce Lewis acid (AlCl).

3D Hierarchically Structured Tin Oxide and Iron Oxide-Embedded Carbon Nanofiber with Outermost Polypyrrole Layer for High-Performance Asymmetric Supercapacitor.

Herein, unique three-dimensional (3D) hierarchically structured carbon nanofiber (CNF)/metal oxide/conducting polymer composite materials were successfully synthesized by combinations of various experimental methods. Firstly, base CNFs were synthesized by carbonization of electrospun PAN/PVP fibers to attain electric double-layer capacitor (EDLC) characteristics. To further enhance the capacitance, tin oxide (SnO) and iron oxide (FeO) were coated onto the CNFs via facile hydrothermal treatment.

Polyaniline-Coated Mesoporous Carbon Nanosheets with Fast Capacitive Energy Storage in Symmetric Supercapacitors.

Polyaniline-capped mesoporous carbon nanosheets with high conductivity and porosity are synthesized by vapor deposition polymerization. The mesoporous carbon template is prepared by removing ordered cubic iron oxide nanocrystals embedded in the carbon matrix obtained by thermal decomposition of an iron-oleate complex in a sodium chloride matrix. The evaporated aniline monomers are slowly polymerized on the carbon surface pretreated with FeCl as an initiator, partially filling the carbon pores to improve conductivity.

Facile Enhancement of Electrochemical Performance of Solid-State Supercapacitor via Atmospheric Plasma Treatment on PVA-Based Gel-Polymer Electrolyte.

A facile oxygen (O) atmospheric plasma treatment is applied to a polyvinyl alcohol (PVA) matrix to enhance its wettability and hydrophilicity. The optimal plasma treatment conditions are determined by varying the applied plasma power and plasma treatment time. A PVA matrix treated with a plasma power of 120 W for 5 s shows the most hydrophilicity owing to successful formation of carbonyl (-CO, >C=O) functional groups without any structural degradation.

Fabrication of Flexible All-Solid-State Asymmetric Supercapacitor Device via Full Recycling of Heated Tobacco Waste Assisted by PLA Gelation Template Method.

In this study, a flexible all-solid-state asymmetric supercapacitor (FASC) device has been successfully fabricated via full recycling of heated tobacco waste (HTW). Tobacco leaves and cellulose acetate tubes have been successfully carbonized (HTW-C) and mixed with metal oxides (MnO and FeO) to obtain highly active materials for supercapacitors. Moreover, poly(lactic acid) (PLA) filters have been successfully dissolved in an organic solvent and mixed with the as-prepared active materials using a simple paste mixing method.

Synthetic Control of Intrinsic Defect Formation in Metal Oxide Nanocrystals Using Dissociated Spectator Metal Salts.

Crystallographic defects are essential to the functional properties of semiconductors, controlling everything from conductivity to optical properties and catalytic activity. In nanocrystals, too, defect engineering with extrinsic dopants has been fruitful. Although intrinsic defects like vacancies can be equally useful, synthetic strategies for controlling their generation are comparatively underdeveloped.

Synthesis of LiDAR-Detectable True Black Core/Shell Nanomaterial and Its Practical Use in LiDAR Applications.

Light detection and ranging (LiDAR) sensors utilize a near-infrared (NIR) laser with a wavelength of 905 nm. However, LiDAR sensors have weakness in detecting black or dark-tone materials with light-absorbing properties. In this study, SiO2/black TiO2 core/shell nanoparticles (SBT CSNs) were designed as LiDAR-detectable black materials.

Hollow TiO Nanoparticles Capped with Polarizability-Tunable Conducting Polymers for Improved Electrorheological Activity.

Hollow TiO2 nanoparticles (HNPs) capped with conducting polymers, such as polythiophene (PT), polypyrrole (PPy), and polyaniline (PANI), have been studied to be used as polarizability-tunable electrorheological (ER) fluids. The hollow shape of TiO2 nanoparticles, achieved by the removal of the SiO2 template, offers colloidal dispersion stability in silicone oil owing to the high number density. Conducting polymer shells, introduced on the nanoparticle surface using vapor deposition polymerization method, improve the yield stress of the corresponding ER fluids in the order of PANI < PPy < PT.

Development of Novel Colorful Electrorheological Fluids.

Herein, the electrorheological (ER) performances of ER fluids were correlated with their colors to allow for the visual selection of the appropriate fluid for a specific application using naked eyes. A series of TiO-coated synthetic mica materials colored white, yellow, red, violet, blue, and green (referred to as color mica/TiO materials) were fabricated via a facile sol-gel method. The colors were controlled by varying the thickness of the TiO coating layer, as the coatings with different thicknesses exhibited different light interference effects.

Spectrally tunable infrared plasmonic F,Sn:InO nanocrystal cubes.

A synthetic challenge in faceted metal oxide nanocrystals (NCs) is realizing tunable localized surface plasmon resonance (LSPR) near-field response in the infrared (IR). Cube-shaped nanoparticles of noble metals exhibit LSPR spectral tunability limited to visible spectral range. Here, we describe the colloidal synthesis of fluorine, tin codoped indium oxide (F,Sn:InO) NC cubes with tunable IR range LSPR for around 10 nm particle sizes.

Smart Fluid System Dually Responsive to Light and Electric Fields: An Electrophotorheological Fluid.

Electrophotorheological (EPR) fluids, whose rheological activity is dually responsive to light and electric fields (E fields), is formulated by mixing photosensitive spiropyran-decorated silica (SP-sSiO) nanoparticles with zwitterionic lecithin and mineral oil. A reversible photorheological (PR) activity of the EPR fluid is developed via the binding and releasing mechanism of lecithin and merocyanine (MC, a photoisomerized form of SP) under ultraviolet (UV) and visible (VIS) light applications. Moreover, the EPR fluid exhibits an 8-fold higher electrorheological (ER) performance compared to the SP-sSiO nanoparticle-based ER fluid (without lecithin) under an E field, which is attributed to the enhanced dielectric properties facilitated by the binding of the lecithin and SP molecules.

Enhanced Electrorheological Performance of Mixed Silica Nanomaterial Geometry.

The mixed geometrical effect on the electrorheological (ER) activity of bimodal ER fluids was investigated by mixing SiO spheres and rods of different dimensions. To gain an in-depth understanding of the mixed geometrical effect, 12 bimodal ER fluids were prepared from 4 sizes of SiO spheres (50, 100, 150, and 350 nm) and 3 types of SiO rods with different aspect ratios (L/D = 2, 3, and 5). Five concentrations of SiO spheres and rods were created for each bimodal ER fluid, resulting in a total of 60 sets of comprehensive ER measurements.

Dual external field-responsive polyaniline-coated magnetite/silica nanoparticles for smart fluid applications.

In this communication, an electromagnetorheological fluid containing FeO/SiO/PANI nanoparticles is reported to demonstrate its controllable rheological properties under electric and magnetic fields. The EMR performance was significantly enhanced under the dual fields in the parallel direction.

A comparative study of the electrorheological properties of various N-doped nanomaterials using ammonia plasma treatment.

A new, simple method is reported to enhance the electrorheological (ER) activity of nanomaterials. Plasma treatment was the ideal technique owing to its ease of use, versatility, and common usage in mass production. Multi-gram quantities of ER nanomaterials with different morphologies, sizes, and compositions were successfully treated by ammonia plasma.

Morphology-controlled mesoporous SiO2 nanorods for efficient scaffolds in organo-metal halide perovskite solar cells.

In meso-superstructured perovskite solar cells, the scaffolding layer, composed of insulating metal oxide nanoparticles, plays an important role in the loading efficiency of the perovskite layer. This communication describes 1D mesoporous silica nanoparticles that were successfully used as scaffolds to enhance the electron extraction from the perovskite absorber layer to the working electrode.