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2D semiconductors have emerged as candidates for next‐generation electronics. However, previously reported 2D transistors which typically employ the gate‐first process to fabricate a back‐gate (BG) configuration while neglecting the thorough impact on the dielectric capping layer, are severely constrained in large‐scale manufacturing and compatibility with complementary metal–oxide–semiconductor (CMOS) technology. In this study, dual‐gate (DG) field‐effect transistors have been realized based on wafer‐scale monolayer MoS2 and the gate‐last processing, which avoids the transfer process and utilizes an optimized top‐gate (TG) dielectric stack, rendering it highly compatible with CMOS technology. Subsequently, the physical mechanism of TG dielectric deposition and the corresponding controllable threshold voltage (VTH) shift is investigated. Then the fabricated TG‐devices with a large on/off ratio up to 1.7 × 109, negligible hysteresis (≈14 mV), and favorable stability. Additionally, encapsulated TG structured photodetectors have been demonstrated which exhibit photo responsivity (R) up to 9.39 × 103 A W−1 and detectivity (D*) ≈2.13 × 1013 Jones. The result paves the way for future CMOS‐compatible integration of 2D semiconductors for complex multifunctional IC applications. [ABSTRACT FROM AUTHOR]

In this study, we have created and investigated ultrathin, large‐size two‐dimensional C2N nanosheets, which serve as promising anode materials for sodium ion batteries. Those ultrathin C2N nanosheets were produced through a chemical vapor deposition process, involving the polymerization of the precursor molecule HAT‐CN on sodium chloride templates. Notably, these nanosheets inherit an abundance of nitrogen sites from the precursor molecules, which are highly advantageous for sodium ion storage. In addition, the ultrathin nature of these nanosheets leads to significantly shorter ion transport pathways, enhancing their capacity for rapid ion storage compared to C2N particles. As a result, the anode constructed using C2N nanosheets demonstrates a notably higher capacity of 335.1 mAh g−1 at 0.5 A g−1, outperforming the 211.5 mAh g−1 of C2N particles. Furthermore, it exhibits outstanding rate performance, achieving 255.4 mAh g−1 at a current density of 2.0 A g−1, along with excellent cycle stability, maintaining a reversible capacity retention of 92.9 % over 1500 cycles at 2.0 A g−1. This research introduces a novel approach to developing high‐capacity anode materials for sodium storage by utilizing carbon nitride materials. [ABSTRACT FROM AUTHOR]

Birnessite MxMnO2 (M = Na+, K+, etc.) has emerged as a promising alternative to the classical MnO2 material owing to its improved pseudocapacitive performance for energy storage. Understanding their structure–property correlation is essential for the development and application of advanced supercapacitors. Herein, we adopt the crystal field theory and density functional simulation to reveal the structural dependence of the pseudocapacitive property of KxMnO2. Attributing to the Jahn–Teller effect of Mn3+, the bandgap of KxMnO2 can be tuned by changing the x value (i.e., the Mn(III)/Mn(IV) ratio). Then, we design a narrow‐bandgap K0.25MnO2 (0.84 eV), which affords a high capacitance of 415 F g−1 at 1 A g−1 and a desirable rate capability of 293 F g−1 at 20 A g−1. Operando Raman spectroscopy confirms that the Jahn–Teller induced structure evolution of [MnO6] octahedron accounts for the superior pseudocapacitive behavior of K0.25MnO2. This finding offers theoretical guidance to the design and application of birnessite materials for pseudocapacitors. [ABSTRACT FROM AUTHOR]

The development of highly safe and low‐cost aqueous batteries is of great significance in the background of carbon neutrality. However, the practical deployment of aqueous batteries has been plagued due to their relatively low capacity and poor cycling stability. Herein, we propose unique conversion electrochemistry of copper selenides for robust and energetic aqueous charge storage. In situ X‐ray diffraction and operando Raman techniques reveal a reversible transformation from CuSe to Cu2Se through the intermediates of Cu3Se2 and Cu1.8Se. Such a conversion process activates the redox carrier of Cu2+ ion and delivers a remarkable rate capability of 285 mAh g−1 at 20 A g−1 and electrochemical durability up to 30,000 cycles. Furthermore, Cu2+ and H+ coinsertion chemistry is proposed to facilitate the conversion process. As a proof‐of‐concept, a hybrid aqueous pouch cell coupling CuSe//Zn is capable of affording maximum energy and power densities of 190 Wh kg–1 and 1366 W kg−1, respectively. [ABSTRACT FROM AUTHOR]

Focuses on a study which analyzed the n-silicon (Si)/i-p-i Si germanium/n-Si structure grown by ultra-high-vacuum chemical molecular epitaxy. Use of cross-sectional transmission electron microscopy and secondary ion mass spectroscopy in the analysis; Experimental procedure; Results and discussion; Conclusion.

Jurassic sandstones in the Xiongcun porphyry copper–gold district, southern Lhasa subterrane, Tibet, China were analysed for petrography, major oxides and trace elements, as well as detrital zircon U–Pb and Hf isotopes, to infer their depositional age, provenance, intensity of source-rock palaeo-weathering and depositional tectonic setting. This new information provides important evidence to constrain the tectonic evolution of the southern Lhasa subterrane during the Late Triassic – Jurassic period. The sandstones are exposed in the lower and upper sections of the Xiongcun Formation. Their average modal abundance (Q21F11L68) classifies them as lithic arenite, which is also supported by geochemical studies. The high chemical index of alteration values (77.19–85.36, mean 79.96) and chemical index of weathering values (86.19–95.59, mean 89.98) of the sandstones imply moderate to intensive weathering of the source rock. Discrimination diagrams based on modal abundance, geochemistry and certain elemental ratios indicate that felsic and intermediate igneous rocks constitute the source rocks, probably with a magmatic arc provenance. The detrital zircon ages (161–243 Ma) and εHf(t) values (+10.5 to +16.2) further constrain the sandstone provenance as subduction-related Triassic–Jurassic felsic and intermediate igneous rocks from the southern Lhasa subterrane. A tectonic discrimination method based on geochemical data of the sandstones, as well as detrital zircon ages from sandstones, reveals that the sandstones were most likely deposited in an oceanic island-arc setting. These results support the hypothesis that the tectonic background of the southern Lhasa subterrane was an oceanic island-arc setting, rather than a continental island-arc setting, during the Late Triassic – Jurassic period. [ABSTRACT FROM AUTHOR]

The n-Si/i-p+-i SiGe/n-Si structure was grown by ultra high vacuum chemical molecular epitaxy, and analysed by high resolution X-ray diffraction, cross-sectional transmission electron microscopy, and secondary ion mass spectroscopy. A high-quality SiGe base layer with an abrupt interface to the Si was obtained. No defects were observed in the n-Si/i-p+-i SiGe/n-Si structure. Both the Ge and boron atoms are uniformly distributed in the p+-SiGe layer, and the changes of profile of both boron and Ge atoms are abrupt from the n-Si to the SiGe layer. A high-performance microwave power SiGe heterojunction bipolar transistor (HBT) was made from the n-Si/i-p+-i SiGe/n-Si structure. Therefore, device-quality n-Si/i-p+-i SiGe/n-Si structures can be grown by ultra high vacuum chemical molecular epitaxy. [ABSTRACT FROM AUTHOR]

To determine whether blood DNA methylation is associated with hepatocellular carcinoma (HCC) for Chinese patients, we used genome-wide DNA methylation detection to access the blood samples of Chinese patients by Illumina Human methylation 450K arrays. Sixty potentially gene locis which had different methylated levels significantly among tumor and adjacent normal tissues would be tested in this study. A previous study was conducted in China communities and followed with 7 years. The DNA from white blood cells (WBC) from 192 patients with HCC and 215 matched controls were assayed in this study. The χ2 test was used to measure data to categorize variables and t -test was used to evaluate the different characteristics among groups. Besides, odds ratios (OR) and 95%CI was calculated for matching factors by conditional logistic regression models. We found that high methylation in WNK2 was related to increased risk of HCC, and high methylation in TPO were related to decreased risk of HCC. In our multivariable conditional logistic regression models, these results all exist. Those findings support the methylated changes of WNK2 and TPO may become a new detection index for HCC patients in clinical laboratory. However, the results should be replicated in additional prospective studies with lager samples.