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The confined defects in 2D van der Waals (vdW)‐layered semiconductors can be easily tailored using charge doping, strain, or an electric field. Nevertheless, gate‐tunable magnetic order via intrinsic defects has been rarely observed to date. Herein, a gate‐tunable magnetic order via resonant Se vacancies in WSe2 is demonstrated. The Se‐vacancy states are probed via photocurrent measurements with gating to convert unoccupied states to partially occupied states associated with photo‐excited carrier recombination. The magneto‐photoresistance hysteresis is modulated by gating, which is consistent with the density functional calculations. The two energy levels associated with Se vacancies split with increasing laser power, owing to the robust Coulomb interaction and strong spin–orbit coupling. The findings offer a new approach for controlling the magnetic properties of defects in optoelectronic and spintronic devices using vdW‐layered semiconductors. The unoccupied energy levels from Se vacancy are tailored from half‐filled to full‐filled to induce the magnetic moment by modulating gate bias under field‐effect transistor in WSe2 semiconductors. The magneto‐photoresistance hysteresis is manifested at the resonant Se‐vacancy energy levels, implying the ferromagnetic order formation. This study opens a venue for 2D van der Waals magnetic semiconductors for future opto‐spintronics.

With the advantage of fast charge transfer, heterojunction engineering is identified as a viable method to reinforce the anodes' sodium storage performance. Also, vacancies can effectively strengthen the Na+ adsorption ability and provide extra active sites for Na+ adsorption. However, their synchronous engineering is rarely reported. Herein, a hybrid of Co0.85Se/WSe2 heterostructure with Se vacancies and N‐doped carbon polyhedron (CoWSe/NCP) has been fabricated for the first time via a hydrothermal and subsequent selenization strategy. Spherical aberration‐corrected transmission electron microscopy confirms the phase interface of the Co0.85Se/WSe2 heterostructure and the existence of Se vacancies. Density functional theory simulations reveal the accelerated charge transfer and enhanced Na+ adsorption ability, which are contributed by the Co0.85Se/WSe2 heterostructure and Se vacancies, respectively. As expected, the CoWSe/NCP anode in sodium‐ion battery achieves outstanding rate capability (339.6 mAh g−1 at 20 A g−1), outperforming almost all Co/W‐based selenides. A hybrid of Co0.85Se/WSe2 heterostructure with Se vacancies and N‐doped carbon polyhedron (CoWSe/NCP) has been fabricated for the first time. The Co0.85Se/WSe2 heterostructure can accelerate charge transfer and the Se vacancies can strengthen the Na+ adsorption ability. As an anode for sodium‐ion batteries, the CoWSe/NCP hybrid achieves outstanding rate performance, outperforming almost all Co/W‐based selenides, together with competitive cycling stability.

Two-dimensional (2D) transition metal dichalcogenides (TMDs) are considered to be promising building blocks for the next generation electronic and optoelectronic devices. Various doping schemes and work function engineering techniques have been explored to overcome the intrinsic performance limits of 2D TMDs. However, a reliable and long-time air stable doping scheme is still lacking in this field. In this work, we utilize keV ion beams of H 2 + to irradiate layered WSe 2 crystals and obtain efficient n-type doping effect for all irradiated crystals within a fluence of 1 × 10 14 protons·cm −2 (1e14). Moreover, the irradiated WSe 2 remains an n-type semiconductor even after it is exposed to ambient conditions for a year. Localized ion irradiation with a focused beam can directly pattern on the sample to make high performance homogenous p-n junction diodes. Raman and photoluminescence (PL) spectra demonstrate that the WSe 2 crystal lattice stays intact after irradiation within 1e14. We attribute the reliable electron-doping to the significant increase in Se vacancies after the proton irradiation, which is confirmed by our scanning transmission electron microscope (STEM) results. Our work demonstrates a reliable and long-term air stable n-type doping scheme to realize high-performance electronic TMD devices, which is also suitable for further integration with other 2D devices.

As is well known, NO2 adsorption plays an important role in gas sensing and treatment because it expands the residence time of compounds to be treated in plasma–catalyst combination. In this work, the adsorption behaviors and mechanism of NO2 over pristine and Se-vacancy defect-engineered WSSe monolayers have been systematically investigated using density functional theory (DFT). The adsorption energy calculation reveals that introducing Se vacancy acould result in a physical-to-chemical adsorption transition for the system. The Se vacancy, the most possible point defect, could work as the optimum adsorption site, and it dramatically raises the transferred-electron quantities at the interface, creating an obviously electronic orbital hybridization between the adsorbate and substrate and greatly improving the chemical activity and sensing sensitivity of the WSSe monolayer. The physical-to-chemical adsorption transition could meet different acquirements of gas collection and gas treatment. Our work broadens the application filed of the Janus WSSe as NO2-gas-sensitive materials. In addition, it is found that both keeping the S-rich synthetic environments and applying compression strain could make the introduction of Se vacancy easier, which provides a promising path for industrial synthesis of Janus WSSe monolayer with Se vacancy.

2D metal‐chalcogenide nanoplatelets (NPLs) exhibit promising photocatalysis properties due to their ultrathin morphology, high surface‐to‐volume ratio, and enhanced in‐plane electron transport mobility. However, NPLs, especially cadmium chalcogenides, encounter challenges in CO2 photoreduction due to insufficient solar energy utilization and fast recombination of photogenerated charge carriers. Defect engineering offers a potential solution but often encounters difficulties maintaining structural integrity, mechanical stability, and electrical conductivity. Herein, by taking two monolayers (2ML) CdSe NPLs as a model system, selenium (Se) vacancies confined in atomic layers can enhance charge separation and conductivity. A straightforward approach to create Se vacancies in various monolayers CdSe NPLs (2, 4, and 5ML) has been developed, enabling efficient CO2 photoreduction with a 4‐fold increase in CO generation compared to their defect‐free counterparts. Significantly, accounting for higher charge density and efficient carrier transport due to Se vacancies, defective 2ML CdSe NPLs (VSe‐2ML CdSe) exhibit CO evolution performance up to 2557.5 µmol g−¹ h−¹ with no significant decay over 5 h, which is an order of magnitude higher than that of common semiconductor catalysts. This study establishes a practical way to design advanced 2D semiconductor photocatalysts to achieve efficient CO2 photoreduction via defect engineering. A direct defect engineering approach is demonstrated to obtain CdSe nanoplatelets with Se vacancies. These nanoplatelets exhibit highly efficient photocatalytic CO₂ reduction performance, achieving a CO evolution rate of up to 2557.5 µmol g−¹ h−¹.

Photocatalytic conversion of carbon dioxide into chemical fuels offers a promising way to not only settle growing environmental problems but also provide a renewable energy source. In this study, through first-principles calculation, we found that the Se vacancy introduction can lead to the transition of physical-to-chemical CO2 adsorption on Janus WSSe nanotube. Se vacancies work at the adsorption site, which significantly improves the amount of transferred electrons at the interface, resulting in the enhanced electron orbital hybridization between adsorbents and substrates, and promising the high activity and selectivity for carbon dioxide reduction reaction (CO2RR). Under the condition of illumination, due to the adequate driving forces of photoexcited holes and electrons, oxygen generation reaction (OER) and CO2RR can occur spontaneously on the S and Se sides of the defective WSSe nanotube, respectively. The CO2 could be reduced into CH4, meanwhile, the O2 is produced by the water oxidation, which also provides the hydrogen and electron source for the CO2RR. Our finding reveals a candidate photocatalyst for obtaining efficient photocatalytic CO2 conversion.

Self-doped n-type PbSe1−δ thermoelectric compounds have been successfully synthesized by the melting and annealing method. The Se vacancies are created by intentionally produced deficiency of Se elements during the sample preparation. Such intrinsic doping can raise the electron concentration to a value as high as 1.2 × 1019 cm−3, leading to greatly improved electrical conductivity and power factor in the n-type PbSe1−δ. Furthermore, the presence of Se vacancies effectively enhances the phonon scattering, resulting in reduced lattice thermal conductivity. Thus, the thermoelectric performance of n-type PbSe1−δ is significantly improved by the formation of intrinsic Se vacancies. The achieved ZT value for the Se-vacancy-rich sample varies from ∼ 0.4 at 330 K to ∼ 1.0 at 675 K, which is comparable to those of the reported n-type PbSe materials with extrinsic doping. In addition, the average ZT of our n-type PbSe system reaches 0.77, which approaches the value of p-type PbTe.

Indium selenides have been considered as highly efficient thermoelectric materials due to their excellent electrical and thermal properties. Herein, we report the effect of Se vacancy on the thermoelectric performance of Pb-doped In 4 Pb 0.01 Se 3− x polycrystalline ( x  = 0, 0.03, 0.07, and 0.1) synthesized by solid state reaction followed by spark plasma sintering. The obtained products are characterized by x-ray powder diffraction, scanning electron microscopy, and transmission electron microscopy. Owing to the increase of Se vacancy in Pb-doped compounds, the electrical resistivity is reduced by increasing carrier concentration along with the reduction of the lattice thermal conductivity. Ultimately, the In 4 Pb 0.01 Se 3− x ( x  = 0.07) exhibits a high ZT value of 0.95 at 690 K.

It is common to find graduates from different fields working in Administration, including in public sector positions, which undermines the construction of administrators' professionalism. This professionalism encompasses a set of elements that foster the development and social recognition of a profession. In this context, this study aimed to analyze the role of the Federal Council of Administration (CFA) and the Regional Council of Administration in Pernambuco (CRA-PE) in constructing the professionalism of administrators in public service exams conducted in the Northeast region of Brazil in 2022. A qualitative research approach was employed, classified as exploratory, descriptive, bibliographic, and documentary. The data were analyzed through content analysis. Among the main findings, three public service exam announcements were identified that allowed candidates from any higher education field to apply for positions specific to Administration. Regarding the verification of professionalism elements in the internal regulations of CFA and CRA-PE, these documents highlighted concerns about the specificity of administrative roles and provided guidelines related to specific knowledge, decision-making power, and membership in the collective body. However, no regulations directly addressing the guidance and oversight of public service exams for positions within the Administration field were identified in the analyzed documents. This gap hinders the strengthening of the administrative profession and, consequently, its professionalism. Keywords: Professionality. Public Service Exams. Professional Councils. Administration. E comum haver graduados em diferentes areas atuando nos campos da Administracao, inclusive em cargos publicos, comprometendo a construcao da profissionalidade dos administradores, visto que esta contempla um conjunto de elementos que promovem o desenvolvimento e o reconhecimento social de uma profissao. Diante disso, a presente pesquisa objetivou analisar o papel do Conselho Federal de Administracao (CFA) e do Conselho Regional de Administracao em Pernambuco (CRA-PE) na construcao da profissionalidade dos administradores no ambito dos concursos publicos realizados na Regiao Nordeste no ano de 2022. Para tanto, realizou-se uma pesquisa de natureza qualitativa, classificando-se como exploratoria, descritiva, bibliografica e documental, cujos dados foram tratados por meio da analise de conteudo. Dentre os principais resultados, foram identificados tres editais de concursos publicos que admitiam a inscricao de candidatos de qualquer area de nivel superior para cargos especificos dos campos da Administracao. No que tange a verificacao dos elementos da profissionalidade nos regimentos internos do CFA e do CRA-PE, constatou-se que esses documentos sinalizam a preocupacao com a especificidade da funcao nos campos da Administracao, bem como apresentam diretrizes relacionadas ao saber especifico, ao poder de decisao e a pertenca ao corpo coletivo. Todavia, nao foram identificadas, nos documentos analisados, normativas diretamente relacionadas a orientacao e a fiscalizacao de concursos publicos no que diz respeito a cargos cujas atribuicoes sao da area de Administracao. Tal lacuna compromete o fortalecimento da classe dos administradores e, consequentemente, a sua profissionalidade. Palavras-chave: Profissionalidade. Concursos Publicos. Conselhos Profissionais. Administracao. Es comun encontrar graduados en diferentes areas actuando en los campos de la Administracion, incluso en cargos publicos, lo que compromete la construccion de la profesionalidad de los administradores, dado que esta abarca un conjunto de elementos que promueven el desarrollo y el reconocimiento social de una profesion. Ante ello, la presente investigacion tuvo como objetivo analizar el papel del Consejo Federal de Administracion (CFA) y del Consejo Regional de Administracion de Pernambuco (CRA-PE) en la construccion de la profesionalidad de los administradores en el ambito de los concursos publicos realizados en la Region Nordeste en el ano 2022. Para ello, se realizo una investigacion de naturaleza cualitativa, clasificada como exploratoria, descriptiva, bibliografica y documental, cuyos datos fueron tratados mediante el analisis de contenido. Entre los principales resultados, se identificaron tres convocatorias de concursos publicos que permitian la inscripcion de candidatos de cualquier area de educacion superior para cargos especificos de los campos de la Administracion. En cuanto a la verificacion de los elementos de la profesionalidad en los reglamentos internos del CFA y del CRA-PE, se constato que estos documentos reflejan preocupacion por la especificidad de las funciones en los campos de la Administracion, ademas de presentar directrices relacionadas con el conocimiento especifico, el poder de decision y la pertenencia al cuerpo colectivo. Sin embargo, no se identificaron en los documentos analizados normativas directamente relacionadas con la orientacion y la fiscalizacion de concursos publicos en lo que respecta a cargos cuyas atribuciones son del area de Administracion. Esta laguna compromete el fortalecimiento de la clase de los administradores y, en consecuencia, su profesionalidad. Palabras clave: Profesionalidad. Concursos Publicos. Consejos Profesionales. Administracion.

Realidad Económica se creó a fines de 1970 para cubrir el vacío que dejaban los grandes medios en relación a los pequeños empresarios, profesionales independientes y trabajadores para los cuáles no había un mensaje; asimismo, se proponía analizar los problemas del país con una mirada argentina.