Ultralow Contact Resistance and Efficient Ohmic Contacts in MoGe₂P₄–Metal Contacts

The MoGe2P4 monolayer, an emerging semiconductor with high carrier mobility, can be proposed as a promising channel material in field effect transistors (FETs). The contact resistance between MoGe2P4 and the metal electrode will limit the performance of a realistic FET. Using density functional theory (DFT) calculations, we explore the contact properties of a MoGe2P4 monolayer with six bulk metal electrodes (In, Ag, Au, Cu, Pd, and Pt). It is demonstrated that the Ohmic contacts are formed in all MoGe2P4–metal contacts due to the strong interfacial interactions, suggesting the high carrier injection efficiency. In addition, the MoGe2P4–Cu, −Pd, and −Pt contacts present 100% tunneling probability due to the absence of the tunneling barrier width. The tunneling probabilities of the MGP–In, MGP–Ag, and MGP–Au contacts are exceptionally higher than those of most other 2D semiconductors. Moreover, the tunneling-specific resistivity of all MoGe2P4–metal contacts is relatively low, indicating an ultralow contact resistance and excellent performance. These findings provide a useful guideline to design high-performance MoGe2P4-based electronic devices

A Self-Supported Porous Hierarchical Core–Shell Nanostructure of Cobalt Oxide for Efficient Oxygen Evolution Reaction

Increasing the active surface area of an electrocatalyst is crucial for effective oxygen evolution reaction (OER). Here, a sophisticated electrode that uses the advantages of porous/hollow nanostructure, hierarchical nanostructure, and self-supported structure simultaneously is demonstrated for the first time. A self-supported porous hierarchical core–shell structure (PHCS) of cobalt oxide is synthesized by the combination of electrochemical deposition and electrochemical treatment. The treatment introduces numerous pores into the core of a core–shell structure, and it decreases the particle size of cobalt oxide to <5 nm, markedly increasing the surface area of the resultant structures. The electrochemical surface area of PHCS is 1.6 greater than that of hierarchical core–shell cobalt oxide, and is ∼20 times greater than that of cobalt oxide nanowires. The PHCS is extremely active in the OER, with the overpotential required for a current density of 100 mA cm^–2 being as small as 300 mV. The Tafel slope is 40.3 mV dec^–1, and the PHCS can work stably for more than 40 h

Generation and Confinement of Long-Lived <i>N</i>‑Oxyl Radical and Its Photocatalysis

Generation of controllable carbon radical under the assistance of <i>N</i>-oxyl radical is an efficient method for the activation of C–H bonds in hydrocarbons. We herein report that irradiation of α-Fe₂O₃ and <i>N</i>-hydroxyphthalimide (NHPI) under 455 nm light generates phthalimide-<i>N</i>-oxyl radical (PINO*), which after being formed by oxidation with holes, is confined on α-Fe₂O₃ surface. The half-life time of the confined radical reaches 22 s as measured by in situ electron paramagnetic resonance (EPR) after the light being turned off. This allows the long-lived <i>N</i>-oxyl radical to abstract the H from C–H bond to form a carbon radical that reacts with molecular oxygen to form R₃C–OO· species, decomposition of which leads to oxygenated products

Silicon Nanowires/Reduced Graphene Oxide Composites for Enhanced Photoelectrochemical Properties

The top of silicon nanowires (SiNWs) arrays was coated with reduced graphene oxide (rGO) by the facile spin-coating method. The resulting SiNWs/rGO composite exhibits enhanced photoelectrochemical properties, with short-circuit photocurrent density more than 4 times higher than that of the pristine SiNWs and more than 600 times higher than that of planar Si/rGO composite. The trapping and recombination of photogenerated carriers at the surface state of SiNWs were reduced after the application of rGO. The results of electrochemical impedance spectroscopy measurements suggest that the reduction of trapping and recombination of photogenerated carriers as well as remarkably enhancement of photoelectrochemical properties can be attributed to the low charge transfer resistance at the SiNWs–rGO interface and rGO–electrolyte interface. The method and results shown here indicate a convenient and applicable approach to further exploitation of high activity materials for photoelectrochemical applications

The use of car safety seats for children in China: A questionnaire survey based on the theory of planned behavior

The purpose of this study was to analyze the psychological characteristics underlying Chinese parents’ behaviors in using child car seats and to understand their decision-making processes. Based on the theory of planned behavior (TPB), three extended variables of perceived accident severity, perceived benefits, and perceived barriers were introduced. From the perspective of social psychology, the psychological factors that influence parents’ use of child car seats and their interrelationships were explored. A questionnaire was designed to collect data, including information on demographic characteristics, basic components of the TPB, and relevant extension variables. Using on online survey, 585 valid questionnaires were collected. Structural equation modeling was used to calibrate the data, and multiple group analysis was performed on the demographic variables. The extended TPB can effectively explain and predict parents’ behaviors when using children’s car seats. The results of the model show that parents’ positive attitudes toward child safety seats (CSSs), others’ recognition of their own use and perceptual control of the use of CSSs increase their willingness to use CSSs. Parents’ willingness to use has a positive impact on the use of CSSs. Additionally, for the three extended variables introduced, perceived benefit significantly promoted parental intention and behavior to use CSS for children; perceived barriers significantly reduced parental use of CSS; and perceived accident severity had no significant effect on parental use of CSS. This study established the validity of the extended TPB model in predicting parents’ behaviors in using car seats for their children. In addition, the current findings may provide a theoretical basis for policy development to promote CSS use.</p

Rh(III)-Catalyzed Acceptorless Dehydrogenative Coupling of (Hetero)arenes with 2‑Carboxyl Allylic Alcohols

Rhodium­(III)-catalyzed C–H activation of (hetero)­arenes and redox-neutral coupling with 2-carboxyl allylic alcohols has been realized for the construction of β-aryl ketones. This reaction occurred efficiently at a relatively low catalyst loading via initial dehydrogenative alkylation to give a β-keto carboxylic acid, followed by decarboxylation

Ni₁₂P₅ Nanoparticles as an Efficient Catalyst for Hydrogen Generation <i>via</i> Electrolysis and Photoelectrolysis

The exploitation of a low-cost catalyst is desirable for hydrogen generation from electrolysis or photoelectrolysis. In this study we have demonstrated that nickel phosphide (Ni₁₂P₅) nanoparticles have efficient and stable catalytic activity for the hydrogen evolution reaction. The catalytic performance of Ni₁₂P₅ nanoparticles is favorably comparable to those of recently reported efficient nonprecious catalysts. The optimal overpotential required for 20 mA/cm² current density is 143 ± 3 mV in acidic solution (H₂SO₄, 0.5 M). The catalytic activity of Ni₁₂P₅ is likely to be correlated with the charged natures of Ni and P. Ni₁₂P₅ nanoparticles were introduced to silicon nanowires, and the power conversion efficiency of the resulting composite is larger than that of silicon nanowires decorated with platinum particles. This result demonstrates the promising application potential of metal phosphide in photoelectrochemical hydrogen generation

An Organic Coprecipitation Route to Synthesize High Voltage LiNi_0.5Mn_1.5O₄

High-voltage cathode material LiNi_0.5Mn_1.5O₄ has been prepared with a novel organic coprecipitation route. The as-prepared sample was compared with samples produced through traditional solid state method and hydroxide coprecipitation method. The morphology was observed by scanning electron microscopy, and the spinel structures were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. Besides the ordered/disordered distribution of Ni/Mn on octahedral sites, the confusion between Li and transition metal is pointed out to be another important factor responsible for the corresponding performance, which is worthy further investigation. Galvanostatic cycles, cyclic voltammetry, and electrochemical impedance spectroscopy are employed to characterize the electrochemical properties. The organic coprecipitation route produced sample shows superior rate capability and stable structure during cycling

Model for the Mass Transport during Metal-Assisted Chemical Etching with Contiguous Metal Films As Catalysts

Metal-assisted chemical etching is a relatively new top-down approach allowing a highly controlled and precise fabrication of Si and Si/Ge superlattice nanowires. It is a simple method with the ability to tailor diverse nanowire parameters like diameter, length, density, orientation, doping level, doping type, and morphology. In a typical metal-assisted chemical etching procedure, a Si substrate is covered by a lithographic noble metal film and etched in a solution containing HF and an oxidant (typically H₂O₂). In general, the function of the metal is to catalyze the reduction of H₂O₂, which delivers electronic holes necessary for the oxidation and subsequent dissolution of the Si oxide by HF. However, the details of the etching process using contiguous metal thin films, especially the mass transport of reactants and byproducts are still not well understood. In this study, the etching mechanism was systematically investigated. Several models of metal-assisted chemical etching using a contiguous metal film as a catalyst were developed and tested by performing different well-controlled etching experiments. The experiments helped to identify two processes fundamental for the formation of Si nanowires. First, a thin porous layer is formed beneath the metal film during etching, which facilitates the transport of the electrolyte (HF and H₂O₂). Second, the porous layer is continuously etched away in an electropolishing process, which occurs in direct contact with the metal film. Our results lead to an improved understanding of the fundamentals of the metal-assisted chemical etching on a microscopic scale. It potentially paves a way to integrate lithography with metal-assisted chemical etching for fabrication of Si nanowires with adjustable surface patterns

Driving anger and its relationships with type A behavior patterns and trait anger: Differences between professional and non-professional drivers

<div><p>The present study examined the types of situations that caused Chinese professional and non-professional drivers to become angry and investigated the differences in driving-elicited anger, considering the influences of type A behavior pattern and trait anger between the two groups. The 20-item revised Driving Anger Scale (DAS) was used to assess a sample of 232 drivers (57% professional, 43% non-professional). The non-professional drivers reported significantly higher levels of anger than the professional drivers on the overall Driving Anger Scale (DAS) and the traffic obstructions and discourtesy subscales. In both groups, the preferred driving speeds were positively related to driving anger. Furthermore, drivers with a type A personality exhibited higher overall driving anger scores and higher anger scores in response to traffic obstructions and slow driving than drivers with a type B personality. Trait anger was significantly related to driving anger in both groups. In the non-professional group, type A behavior patterns (TABPs) and time hurry (TH) were positively correlated with anger evoked by slow driving. In the professional group, TABPs, TH and competitive hostility (CH) were positively related to driving anger, and the TABPs exerted an indirect effect on driving anger by mediating the influence of trait anger. Overall, these findings provide a theoretical basis for implementing targeted interventions for driving anger in both professional and non-professional drivers.</p></div