Growth-based monolithic 3D integration of single-crystal 2D semiconductors.

The demand for the three-dimensional (3D) integration of electronic components is steadily increasing. Despite substantial processing challenges, the through-silicon-via (TSV) technique emerges as the only viable method for integrating single-crystalline device components in a 3D format. Although monolithic 3D (M3D) integration schemes show promise, the seamless connection of single-crystalline semiconductors without intervening wafers has yet to be demonstrated.

Junctionless Negative-Differential-Resistance Device Using 2D Van-Der-Waals Layered Materials for Ternary Parallel Computing.

Negative-differential-resistance (NDR) devices offer a promising pathway for developing future computing technologies characterized by exceptionally low energy consumption, especially multivalued logic computing. Nevertheless, conventional approaches aimed at attaining the NDR phenomenon involve intricate junction configurations and/or external doping processes in the channel region, impeding the progress of NDR devices to the circuit and system levels. Here, an NDR device is presented that incorporates a channel without junctions.

A Van Der Waals Reconfigurable Multi-Valued Logic Device and Circuit Based on Tunable Negative-Differential-Resistance Phenomenon.

Multi-valued logic (MVL) technology that utilizes more than two logic states has recently been reconsidered because of the demand for greater power saving in current binary logic systems. Extensive efforts have been invested in developing MVL devices with multiple threshold voltages by adopting negative differential transconductance and resistance. In this study, a reconfigurable, multiple negative-differential-resistance (m-NDR) device with an electric-field-induced tunability of multiple threshold voltages is reported, which comprises a BP/ReS heterojunction and a ReS /h-BN/metal capacitor.

High-Efficiency WSe Photovoltaic Devices with Electron-Selective Contacts.

A rapid surge in global energy consumption has led to a greater demand for renewable energy to overcome energy resource limitations and environmental problems. Recently, a number of van der Waals materials have been highlighted as efficient absorbers for very thin and highly efficient photovoltaic (PV) devices. Despite the predicted potential, achieving power conversion efficiencies (PCEs) above 5% in PV devices based on van der Waals materials has been challenging.

Selective Hydrogenation of Acetylene to Ethylene Over Nanosized Gold and Palladium Supported Catalysts.

Ethylene, the main raw material for polyethylene production, is a by-product produced by thermally decomposing naphtha and it contains a small amount of acetylene. The acetylene reacts as a permanent catalyst poison for the ethylene polymerization catalyst. In this study, we wanted to improve the acetylene conversion and the ethylene selectivity by selective hydrogenation of acetylene for removing acetylene contained in ethylene.

Characterization of Cotton Ball-like Au/ZnO Photocatalyst Synthesized in a Micro-Reactor.

Noble metal/metal oxide nanostructures are an efficient system in photocatalysis. Continuous and scalable production of advanced particle systems will be a requirement for commercial-scale deployment for many applications, including photocatalysis. In this work, Au/ZnO structures were synthesized in a continuous flow micro-reactor at room temperature and the detailed characteristics of the product indicate a specific cotton ball-like core-shell microstructure that showcases specific advantages compared to traditional batch synthesis methods.

A Synthesis of Alkoxylates from Styrenated Phenols and Ethylene Carbonate Over KOH/La₂O₃ Catalysts.

Styrenated phenol alkoxylates (SP-A) are prepared from styrenated phenols (SP) and ethylene oxide (EO) under a homogeneous base catalyst. However, to use EO that is difficult to handle, a high-pressure reaction device capable of reaction process control should be used. Additionally, the homogeneous base catalyst requires a neutralization process to remove the remaining catalyst after the reaction, and it is difficult to separate the catalysts and the product.

Preparation of Styrenated Phenol Over SO₄/ZrO₂ Catalyst in a Large-Scale Synthesis Process.

Styrenated phenols (SPs) are usually synthesized by the reaction of styrene and phenol under acid catalysts. SPs with a high content of di-styrenated phenol (DSP) can be used to prepare styrenated phenol alkoxylate (SP-A). Therefore, in this study, a scale-up process for synthesizing SPs with high DSP content which can be used for synthesis of SP-A was studied.

Preparation of Styrenated Phenol by Alkylation of Phenol with Styrene Over SO₄²⁻ /ZrO₂ Catalyst.

Styrenated phenols are usually synthesized by the reaction of styrene and phenol under acid catalysts. Styrenated phenol involving high content of di-styrenated phenol (DSP) was synthesized, which can be used to prepare styrenated phenol alkoxylate. The solid catalyst used in this study was prepared by impregnation method.

Effect of Gold Nanoparticles Addition to CuO–ZnO/A₂O₃ Catalyst in Conversion of Carbon Dioxide to Methanol.

Hydrogenation of carbon dioxide (CO₂) into methanol (CH₃OH) was carried out in the CuO–ZnO based supported gold catalyst prepared by the co-precipitation method. When gold nanoparticles were added to the CuO–ZnO/Al2O₃ catalysts (CuO–ZnO/Au/Al₂O₃), the CO₂ conversion and CH₃OH yield were increased (two times higher than that of CuO–ZnO/Al₂O₃ catalyst) with increasing reaction pressure, but selectivity of CH3OH was decreased. The main reason of this result could suggest the importance gold-oxides interface in CH₃OH formation through hydrogenation of CO₂.

Facile Synthesis and Characterization of Zinc Oxide Nanoparticle on Activated Carbon Using Liquid Phase Plasma Method.

Zinc oxide/activated carbon nanocomposites were synthesized by impregnating zinc oxide nanoparticles onto activated carbon powder using liquid phase plasma (LPP) method. Zinc oxide nanoparticles on the surface of activated carbon were fabricated rapidly by the LPP method due to reducing the zinc ion in aqueous solution. The obtained zinc oxide/activated carbon nanocomposites were characterized by XPS, HRTEM, and EDS.

A Study on Synthesis of Styrenated Phenol Over Al · Ni/SiO₂-Supported Catalysts.

Styrenated phenol was prepared by an alkylation of phenol using NiCl2 and AlCl3 supported on silica gel. The conversion of phenol and styrene of alkylation reaction, and the selectivity of styrenated phenol were investigated. The Al · Ni/SiO2 Supported catalyst was used, the conversion of phenol was almost 100%.

A Study on H₂SO₄-Treated MO Catalysts for Styrenated Phenols by Alkylation of Phenol with Styrene.

Styrenated phenols (SPs) involving very small amount of unreacted phenol and high content of di-SP (DSP) were synthesized, which can be used to prepare SP alkoxylate. The solid catalyst was prepared by impregnation method. SO2-4 on SO2-4/MxOy catalyst was introduced from an aqueous 1M-H2SO4 solution.

Precipitation of Nickel Oxide on TiO₂ Photocatalysts for Enhanced Visible Degradation Activity.

The liquid phase plasma (LPP) synthetic process has been exploited to synthesize nickel oxide nanoparticles doped TiO2 photocatalyst (NOTP) that can respond to visible light. The physicochemical properties of NOTPs were studied by several analysis instruments. The nickel oxide nanoparticles precipitated uniformly on the TiO2 powder are mostly NiO.

Effect of Molar Concentration of NH4OH on Photocatalytic Activity in Preparation of Nanosized TiO2 Powder from Spent Titanium Chip by Sol-Gel Method.

The TiO2 powder was prepared from the spent titanium chips by applying the sol-gel method. The spent titanium chip was dissolved in HCl solution, and then NH4OH solution was added. The molar concentration of NH4OH solution was 2 M, 4 M, 8 M, and 10 M.

Synthesis Process of Copper/Graphene Nanocomposite by the Liquid Phase Plasma Reduction Method.

Liquid phase plasma (LPP) process was applied to the impregnation of copper nanoparticles onto graphene sheet. Approximately 30-50 nm sized tetragonal nanoparticles were dispersed uniformly on the surface of the two-dimensional graphene sheet. The amount of copper nanoparticles precipitated increased with increasing LPP process time.

Synthesis and Characterization of Platinum(II) Complexes with Various Substituted 2,2'-Bipyridine Ligands.

The reaction of platinum 5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)di-2,2'-bipyridine with 2,2'-bipyridine) PtCI2, (1,10-phenanthroline)PtC2 and (2,2'-bipyrimidine)PtC2: (2,2'-bipyridine)Pt[5,5"-(9,9-dioctyl-9H- fluorene-2,7-diyl)di-2,2'-bipyridine] (1) (2,2'-bipyrimi-dine)Pt[5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)di- 2,2'-bipyridine] (2) (1,10-Phenantroline)-Pt[5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)di-2,2'-bipyridine] (3). In the study, new platinum complex compounds were synthesized utilizing the ligand of a 5,5"-(9,9- dioctyl-9H-fluorene-2,7-diyl)di-2,2'-bipyridine). Each of the three complexes was obtained through the reaction carried out in this study.

Catalytic Activity of Nanosized CuO-ZnO Supported on Titanium Chips in Hydrogenation of Carbon Dioxide to Methyl Alcohol.

In this study, titanium chips (TC) generated from industrial facilities was utilized as TiO2 support for hydrogenation of carbon dioxide (CO2) to methyl alcohol (CH3OH) over Cu-based catalysts. Nano-sized CuO and ZnO catalysts were deposited on TiO2 support using a co-precipitation (CP) method (CuO-ZnO/TiO2), where the thermal treatment of TC and the particle size of TiC2 are optimized on CO2 conversion under different reaction temperature and contact time. Direct hydrogenation of CO2 to CH3OH over CuO-ZnO/TiO2 catalysts was achieved and the maximum selectivity (22%) and yield (18.

Preparation of Nanosized TiO2 Powder from Spent Titanium Chip by Sol-Gel Method.

The TiO2 powder was prepared from the spent titanium chips by applying the sol-gel method with neutralization by NaOH solution. The prepared TiO2 powder was characterized using a particle size analysis, BET surface area, and XRD analysis. The crystal structure of the TiO2 powder was rutile type, and the powder was obtained to be nanosized.

Preparation of Aluminum Nanoparticles Using Bipolar Pulsed Electrical Discharge in Water.

Al nanoparticles were synthesized in liquid phase plasma using Al chloride as the precursor. CTAB was used as the surfactant to obtain well dispersed particles. When the surfactant was not added, large aggregated particles were generated.

A Study of Phosphorescent Light Emitting Using Cyclometalated Pt(II) Complexes.

The reaction of platinum [Pt(4-(N,N-bis(piridyl)amino)stilbene)]Cl2 with 5,5"-(9,9-dioctyl-9H-fluorene- 2,7-diyl)di-2,2'-bipyridine, 2,2'-bipyridine, and 1,10-phenathroline affords the following complexes: [(4-(N,N-bis(piridyl)amino)stilbene)Pt(5,5"-(9,9-dioctyl-9H-fluorene-2,7-diyl)di-2,2'-bipyridine)] (1), [(4-(N,N-bis(piridyl)amino)stilbene)Pt(2,2'-bipyridine)] (2), and [(4-(N,N-bis(piridyl)amino)stilbene) Pt(1,10-phenathroline)] (3). In this study, new platinum complex compounds were synthesized utilizing the ligand of a 4-(N,N-bis(piridyl)amino)stilbene system. These complexes were analyzed using a 1H(13C)-NMR, UV-vis and PL spectrophotometer.

Bimetallic Pt-Au Nanocatalysts on ZnO/Al2O3/Monolith for Air Pollution Control.

The catalytic activity of a monolithic catalyst with nanosized Pt and Au particles on ZnO/Al2O3 (Pt-Au/ZnO/Al2O3/M) prepared by a wash-coat method was examined, specifically for toluene oxidation. Scanning electron microscopy image showed clearly the formation of a ZnO/Al2O3 layer on the monolith. Nanosized Pt-Au particles on ZnO/Al2O3/M with different sizes could be found in the Pt-Au/ZnO/Al2O3/M catalyst.

The Characteristics of an Antibacterial TiAgN Thin Film Coated by Physical Vapor Deposition Technique.

In this work, we found the characteristics of an antibacterial TiAgN thin film coated on the pure titanium specimen via the physical vapor deposition process (PVD). TiAgN thin films were coated using TiAg alloy targets by arc ion plating method. Changing the process parameters, the surface analysis of TiAgN thin film was observed by FE-SEM and the force of adhesion was measured with Scratch Tester.

The Effect of Zinc Oxide Addition to Alumina-Supported Gold Catalyst in Low Temperature Carbon Monoxide Oxidation.

Gold catalysts supported on alumina (Au/Al2O3) and zinc oxide/Al2O3 (Au/ZnO/Al2O3) were prepared by deposition-precipitation with ammonium bicarbonate, and were characterized by nitrogen gas adsorption, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and temperature programmed reduction. The effect of ZnO addition to the surface of Al2O3 on the catalytic activity of Al2O3-supported gold catalysts in carbon monoxide oxidation is discussed in detail. The additions of 4 wt% ZnO loading to Au/Al2O3 showed a higher degree of gold particle dispersion which resulted in higher catalytic activity with Au/ZnO/Al2O3 catalyst than with Au/Al2O3 catalyst.