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Based on first-principles calculations in the density functional theory, we systematically investigated the possible interface structure, magnetism, and electronic properties of the all-Heusler alloy Co2MnGe/CoTiMnGe(100) heterojunction. The calculation indicated that the Co2MnGe Heusler alloy is a half-metal with a magnetic moment of 4.97 μ^ CoTiMnGe is a narrow-band gap semiconductor and may act as an ultra-sensitive photocatalyst. We cannot find an "ideal" spin-polarization of 100% in CoCo termination and MnGe termination. Due to the interface interaction, the direct magnetic hybridization or indirect RKKY exchange will be weakened, leading to an increase in the atomic magnetic moment of the interfacial layer. For eight possible heterojunction structures, the half-metallic gaps in the Co2MnGe bulk have been destroyed by the inevitable interface states. The spin-polarization value of 94.31% in the CoCo-TiGe-B heterojunction revealed that it is the most stable structure. It is feasible to search for high-performance magnetic tunnel junction by artificially constructing suitable all-Heusler alloy heterojunctions. [ABSTRACT FROM AUTHOR]

Stacking engineering is a popular method to tune the performance of two-dimensional materials for advanced applications. In this work, Jansu MoSSe and WSSe monolayers are constructed as a van der Waals (vdWs) heterostructure by different stacking configurations. Using first-principle calculations, all the relaxed stacking configurations of the MoSSe/WSSe heterostructure present semiconductor properties while the direct type-II band structure can be obtained. Importantly, the Z-scheme charge transfer mode also can be addressed by band alignment, which shows the MoSSe/WSSe heterostructure is an efficient potential photocatalyst for water splitting. In addition, the built-in electric field of the MoSSe/WSSe vdWs heterostructure can be enhanced by the S-Se interface due to further asymmetric structures, which also results in considerable charge transfer comparing with the MoSSe/WSSe vdWs heterostructure built by the S-S interface. Furthermore, the excellent optical performances of the MoSSe/WSSe heterostructure with different stacking configurations are obtained. Our results provide a theoretical guidance for the design and control of the two-dimensional heterostructure as photocatalysts through structural stacking., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Ren, Liu, Ma, Ren, Cui and Mu.)

This work prepared an ISAPO-34/SAPO-18 intergrown zeolite using phosphate organoamine as the structure guiding agent. Physical-chemical characterizations by XRD, SEM, TG, and BET showed that the SAPO-34/SAPO-18 presents a cross-stacked cubic block-like microscopic morphology, with characteristic diffusive diffraction peaks at 2θ = 16-18° and 30-33° and a specific surface area of 557 m 2  g -1 . The series of copper-based catalysts prepared from SAPO-34/SAPO-18 showed a shift of the active temperature window to a lower temperature with increasing copper content. Moreover, the Brønsted acid site decreased significantly due to copper ion exchange and zeolite structure framework damage. Among them, the 1.2 wt% sample showed the widest active temperature window, with a T 90 range of 175-435°C. After low-temperature hydrothermal aging treatment, the zeolite structure was eroded and the catalyst activity deteriorated significantly., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Ye, Ren, Wang and Wang.)

Two-dimensional van der Waals (vdW) heterostructures reveal novel properties due to their unique interface, which have attracted extensive focus. In this work, the first-principles methods are explored to investigate the electronic and the optical abilities of the heterostructure constructed by monolayered MoTe 2 and PtS 2 . Then, the external biaxial strain is employed on the MoTe 2 /PtS 2 heterostructure, which can persist in the intrinsic type-II band structure and decrease the bandgap. In particular, the MoTe 2 /PtS 2 vdW heterostructure exhibits a suitable band edge energy for the redox reaction for water splitting at pH 0, while it is also desirable for that at pH 7 under decent compressive stress. More importantly, the MoTe 2 /PtS 2 vdW heterostructure shows a classy solar-to-hydrogen efficiency, and the light absorption properties can further be enhanced by the strain. Our results showed an effective theoretical strategy to tune the electronic and optical performances of the 2D heterostructure, which can be used in energy conversion such as the automotive battery system., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhang, Ren, Cheng, Cui and Li.)

Recently, the energy shortage has become increasingly prominent, and hydrogen (H 2 ) energy has attracted extensive attention as a clean resource. Two-dimensional (2D) materials show excellent physical and chemical properties, which demonstrates considerable advantages in the application of photocatalysis compared with traditional materials. In this investigation, based on first-principles methods, 2D PtS 2 and MoTe 2 are selected to combine a heterostructure using van der Waals (vdW) forces, which suggests a type-II band structure to prevent the recombination of the photogenerated charges. Then, the calculated band edge positions reveal the decent ability to develop the redox reaction for water splitting at pH 0. Besides, the potential drop between the PtS 2 /MoTe 2 vdW heterostructure interface also can separate the photogenerated electrons and holes induced by the charge density difference of the PtS 2 and MoTe 2 layers. Moreover, the fantastic optical performances of the PtS 2 /MoTe 2 vdW heterostructure further explain the promising advanced usage for photocatalytic decomposition of water., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Shao, Ren, Huang, Yang and Cui.)

Recently, expanding the applications of two-dimensional (2D) materials by constructing van der Waals (vdW) heterostructures has become very popular. In this work, the structural, electronic and optical absorption performances of the heterostructure based on AlN and Zr 2 CO 2 monolayers are studied by first-principles simulation. It is found that AlN/Zr 2 CO 2 heterostructure is a semiconductor with a band gap of 1.790 eV. In the meanwhile, a type-I band structure is constructed in AlN/Zr 2 CO 2 heterostructure, which can provide a potential application of light emitting devices. The electron transfer between AlN and Zr 2 CO 2 monolayer is calculated as 0.1603 | e | in the heterostructure, and the potential of AlN/Zr 2 CO 2 heterostructure decreased by 0.663 eV from AlN layer to Zr 2 CO 2 layer. Beisdes, the AlN/Zr 2 CO 2 vdW heterostructure possesses excellent light absorption ability of in visible light region. Our research provides a theoretical guidance for the designing of advanced functional heterostructures., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Ren, Zheng, Lou, Yu, Sun and Li.)