Achieving Extraordinary Power Factors in GeTe Epitaxial Films through Carrier Transport Engineering.

GeTe-based films have attracted tremendous attention from the thermoelectric community owing to their excellent thermoelectric performance. It is vital to reduce the hole density and maintain a high carrier mobility for GeTe films; however, this remains a significant challenge. To overcome this drawback, we succeeded in fabricating high-crystalline quality GeTe-based films and remarkably improve their electrical properties using molecular beam epitaxy under a low substrate temperature and optimized Te/GeTe flux ratios.

The Relationship Between Social Anxiety and Depression Among Rural High School Adolescents: The Mediating Role of Social Comparison and Social Support.

: This study aimed to explore the impact of social anxiety on depression among high school students and examine the parallel mediating roles of social comparison and social support. : A total of 806 rural high school students were surveyed using the Short Mood and Feelings Questionnaire, the Social Phobia Inventory, the Chinese version of the Social Comparison Orientation Scale, and the Multidimensional Scale of Perceived Social Support. : Social anxiety and social comparison were significantly and positively correlated with depression, while social support exhibited a significant negative correlation with depression.

Thermoelectric Performance and Stability of Industrially Zone-Melted P-Type BiSbTe Alloys with High Te Doping.

In the preparation process of p-type BiSbTe alloys, conventional powder metallurgy techniques often use excess Te to optimize the performance. Large-scale industrial zone melting also attempts to compensate for Te during raw material preparation. However, it is unclear whether the thermoelectric performance of p-type BiSbTe improves with excess Te in industrial production as well as the thermal stability of the material and devices.

Significant Enhancement in the Thermoelectric Performance of the MnSbTe Topological Insulator through Vacancy Regulation and Lattice-Softening Strategies.

The topological insulator MnSbTe shows promising potential in thermoelectric applications due to its intrinsically low lattice thermal conductivity. However, its thermoelectric performance is limited by the high carrier concentration, of which the origin is still unclear. In this work, the carrier concentration is successfully tuned from 2.

Current induced electromechanical strain in thin antipolar AgSe semiconductor.

Electromechanical coupling permits energy conversion between electrical and elastic forms, with wide applications. This conversion is usually observed in dielectric materials as piezoelectricity and electrostriction. Electromechanical coupling response has also been observed in semiconductors, however, the mechanism in semiconductors with a small bandgap remains contentious.

Concurrently High Thermoelectric and Magnetocaloric Performance of BiSbTe/NiMnIn Composites for All-Solid-State Thermoelectromagnetic Refrigeration.

Materials with both high thermoelectric (TE) performance and excellent magnetocaloric (MC) properties near room temperature are of great importance for all-solid-state TE/MC hybrid refrigeration. A combination of such two critical characteristics, however, is hardly attainable in single phase compounds. Herein we report a composite material that comprises Bi-Sb-Te thermoelectric and Ni-Mn-In magnetocaloric components as an innovative thermoelectromagnetic material with dual functionalities.

Protective and risk factors of anxiety in children and adolescents during COVID-19: A systematic review and three level meta-analysis.

Background: In order to gain a deepened understanding of the impact of public health emergency and to develop effective interventions and preventions, this study aimed to evaluate risk and protective factors associated with anxiety in children and adolescents and to explore potential moderators in the background of COVID-19 within the framework of socio-ecological model.

Methods: A literature search was conducted in Web of Science, MEDLINE, PubMed, Scopus, EBSCO, ScienceDirect, Emerald, and CNKI for studies published from early 2020 to early 2023 that examined factors associated with anxiety among children and adolescents with age range of 6 to 17 years old. Random effects models and a three-level meta-analytic approach were used.

Stereoactive Lone-Pair Manipulation for High Thermoelectric Performance of GeSe-Based Compounds.

Materials with high crystallographic symmetry are supposed to be good thermoelectrics because they have high valley degeneracy () and superb carrier mobility (μ). Binary GeSe crystallizes in a low-symmetry orthorhombic structure accompanying the stereoactive 4s lone pairs of Ge. Herein, we rationally modify GeSe into a high-symmetry rhombohedral structure by alloying with GeTe based on the valence-shell electron-pair repulsion theory.

Operando Observation of Electrically Triggered Phase Transition in Thin CuS Crystal.

CuS has been identified as a functional material of memristors with multilevel resistance switching. However, as the migration of Cu ions under the electric field is tangled with defect evolution and phase transition, the electroresistance mechanism of CuS remains largely unclear. Here, the electrically triggered phase transition was studied by transmission electron microscopy.

The association between child maltreatment and academic achievement: A systematic review and meta-analysis.

Background: Although the association between child maltreatment and academic performance has been well-established, the magnitude of these associations remains unclear.

Objective: This study aims to summarize the associations between child maltreatment and its subtypes (physical, emotional, sexual abuse, and neglect) and academic achievement (general achievement, language arts, and math) as well as to explore potential moderators.

Participants And Setting: This present meta-analysis included 59 studies with 211,568 participants, of which 50.

Roadmap for Power Generation of Industrial Hot Extruded BiTe-Based Thermoelectric Device in Real-World Heat Sources.

Recovering waste heat through thermoelectric (TE) technology is critical for enhancing energy efficiency. However, commercial devices often require n- and p-type thermoelectric units to have similar cross-sectional areas and conductivities, complicating optimization of their figure of merit (). Moreover, real-world heat sources are not constant temperature sources, and only heat flux can be measured.

In Situ STEM Observation of Phase Transition Triggered by Mo Migration in MoTe.

The heterostructure of transition metal dichalcogenides (TMDs), such as one-dimensional (1D) nanowires embedded in two-dimensional (2D) nanosheets, has drawn much research attention due to its unique electronic, spintronic, magnetic, and catalytic properties. The general approach for preparing such a heterostructure is through electron beam lithography or annealing on the 2D template, triggering direct formation of the 1D component within the 2D matrix. However, the thermodynamic mechanism behind the transition from 2D to 1D is still not well clarified.

Social anxiety and bullying victimization: A three-level meta-analysis of cross-sectional and longitudinal studies.

Background: Numerous studies have explored the association between social anxiety and bullying victimization. However, inconsistency are found regarding the strength and the direction of this relationship. Moreover, it remains unclear how different subtypes of bullying victimization associate with social anxiety.

Two-Dimensional-Like Phonons in Three-Dimensional-Structured Rhombohedral GeSe-Based Compounds with Excellent Thermoelectric Performance.

The coupling of charge and phonon transport in solids is a long-standing issue for thermoelectric performance enhancement. Herein, two new narrow-gap semiconductors with the same chemical formula of GeSeTe (GST) are rationally designed and synthesized: one with a layered hexagonal structure (H-GST) and the other with a non-layered rhombohedral structure (R-GST). Thanks to the three-dimensional (3D) network structure, R-GST possesses a significantly larger weighted mobility than H-GST.

Rational Design of Cu Vacancies and Antisite Defects for Boosting the Thermoelectric Properties of CuGaTe-Based Compounds.

CuGaTe-based compounds show great promise in the application for high-temperature thermoelectric power generation; however, its wide bandgap feature poses a great challenge for enhancing thermoelectric performance via structural defects modulation and doping the system. Herein, it is discovered that the presence of Ga antisite defects in the CuGaTe compound promotes the formation of Cu vacancies, and vice versa, which tends to form the charge-neutral structure defects combination with one Ga antisite defect and two Cu vacancies. The accumulation of Cu vacancies in the structure of the (CuTe)(GaTe) compounds evolves into twins and stacking faults.

High Ductility and Excellent Thermoelectric Performance in Te-Stabilized Cubic AgTeS Solid Solutions.

The stabilization at low temperatures of the AgS cubic phase could afford the design of high-performance thermoelectric materials with excellent mechanical behavior, enabling them to withstand prolonged vibrations and thermal stress. In this work, we show that the AgTeS solid solutions, with Te content within the optimal range 0.20 ≤ ≤ 0.

Unraveling electronic origins for boosting thermoelectric performance of p-type (Bi,Sb)Te.

P-type BiSbTe compounds are crucial for thermoelectric applications at room temperature, with BiSbTe demonstrating superior performance, attributed to its maximum density-of-states effective mass (*). However, the underlying electronic origin remains obscure, impeding further performance optimization. Herein, we synthesized high-quality BiSbTe (00 ) films and performed comprehensive angle-resolved photoemission spectroscopy (ARPES) measurements and band structure calculations to shed light on the electronic structures.

Heterogeneous-Structure-Based AuNBs@TiO Nano-Photosensitizers for Computed Tomography Imaging Guided NIR-II Photodynamic Therapy and Cancer Metastatic Prevention.

Photodynamic therapy (PDT) is a minimally invasive cancer treatment that, despite its significant attention, faces limitations in penetration depth, which restrict its effectiveness. Herein, it is found that gold nanobipyramid (AuNBs) coated with TiO can form a core-shell heterogeneous structure (AuNBs@TiO) with strong absorption at second near infrared (NIR-II) region. A substantial quantity of reactive oxygen species (ROS), including singlet oxygen (O), superoxide anion radicals, and hydroxyl radicals, can be rapidly generated when subjecting the AuNBs@TiO aqueous suspension to 1064 nm laser irradiation.

Rapid low-temperature densification of AgSe bulk material: mass transfer through the dissociative adsorption reaction of Ag protrusions and Se saturated vapor.

In materials science, the impact of density on a material's capabilities is profound. Conventional sintering requires high temperatures and is energy-demanding, propelling the pursuit of less intensive, low-temperature densification methods. Electric field-assisted sintering has recently gained attention for its simplicity and effectiveness, offering a new frontier in low-temperature densification.

Dual-Cation CuAgSe-Based Material: Rapid Mass Transfer in Synthesis and High Thermoelectric Performance Realization.

Understanding mass transfer mechanisms is vital for developing new material synthesis and densification technologies. Ion transport, serving both mass and charge transfer, is essential for the rapid preparation of high-performance fast ionic conductor thermoelectric materials like ZnSb and CuQ (Q = S, Se). In the case of dual-cation fast ion conductor materials like CuAgSe, exploring the relationship between cation transport becomes pertinent.

Topological Electronic Transition Contributing to Improved Thermoelectric Performance in p-Type MgSb Bi Solid Solutions.

Topological electronic transition is the very promising strategy for achieving high band degeneracy (N) and for optimizing thermoelectric performance. Herein, this work verifies in p-type MgSb Bi that topological electronic transition could be the key mechanism responsible for elevating the N of valence band edge from 1 to 6, leading to much improved thermoelectric performance. Through comprehensive spectroscopy characterizations and theoretical calculations of electronic structures, the topological electronic transition from trivial semiconductor is unambiguously demonstrated to topological semimetal of MgSb Bi with increasing the Bi content, due to the strong spin-orbit coupling of Bi and the band inversion.

Regulating Local Atomic Environment around Vacancies for Efficient Hydrogen Evolution.

Defect engineering is essential for the development of efficient electrocatalysts at the atomic level. While most work has focused on various vacancies as effective catalytic modulators, little attention has been paid to the relation between the local atomic environment of vacancies and catalytic activities. To face this challenge, we report a facile synthetic approach to manipulate the local atomic environments of vacancies in MoS with tunable Mo-to-S ratios.

The Failure Mechanism of Micro Thermoelectric Devices under the Action of the Temperature Field.

The micro thermoelectric device (m-TED) boasts features such as adjustable volume, straightforward structure, and precise, rapid temperature control, positioning it as the only current solution for managing the temperature of microelectronic systems. It is extensively utilized in 5G optical modules, laser lidars, and infrared detection. Nevertheless, as the size of the m-TED diminishes, the growing proportion of interface damages the device's operational reliability, constraining the advancement of the m-TED.

Nature of Thermal Hysteresis of Thermoelectric Properties in AgTeS Compounds.

AgTeS usually undergo various phase structures upon heating or cooling processes; however, the correlation between the heat treatment, the phase structure, and the physical properties is still a controversy. Herein, three different phases are realized for AgTeS (0.35 ≤ ≤ 0.

Exploring the Epitaxial Growth Kinetics and Anomalous Hall Effect in Magnetic Topological Insulator MnBiTe Films.

The discovery of MnBiTe-based intrinsic magnetic topological insulators has fueled tremendous interest in condensed matter physics, owing to their potential as an ideal platform for exploring the quantum anomalous Hall effect and other magnetism-topology interactions. However, the fabrication of single-phase MnBiTe films remains a common challenge in the research field. Herein, we present an effective and simple approach for fabricating high-quality, near-stoichiometric MnBiTe films by directly matching the growth rates of intermediate BiTe and MnTe.