The g-C 3 N 4 -based composite structure exhibits excellent photocatalytic performance. However, their photogenerated carrier transfer and photocatalytic reaction mechanism were unclear. In this study, a 2D/2D g-C 3 N 4 /SnS 2 heterojunction was systematically investigated by a hybrid density functional approach. Results indicated that the g-C 3 N 4 /SnS 2 heterojunction was a staggered band alignment structure, and band bending occurred at the interface. A built-in electric field from the g-C 3 N 4 surface to the SnS 2 surface was formed by interfacial interaction. During visible-light irradiation, excited electrons in the conduction band maximum (CBM) of SnS 2 easily recombined with the holes in the VBM of g-C 3 N 4 under the electric field force. As a result, photogenerated electrons and holes naturally accumulate at the CBM of g-C 3 N 4 and the valence band maximum (VBM) of SnS 2 , respectively. The effective separation of holes and electrons in space was advantageous to them participating in catalytic reactions on a different surface. Consequently, a direct Z-scheme photocatalytic reaction mechanism was established to enhance the photocatalytic activity of the g-C 3 N 4 /SnS 2 heterojunction. Our results not only reveal the photocatalytic reaction mechanism of the g-C 3 N 4 /SnS 2 heterojunction but also provide a theoretical guidance for the design and preparation of novel g-C 3 N 4 -based composite structures.

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In transition‐metal‐oxide heterostructures, the anomalous Hall effect (AHE) is a powerful tool for detecting the magnetic state and revealing intriguing interfacial magnetic orderings. However, achieving a larger AHE at room temperature in oxide heterostructures is still challenging due to the dilemma of mutually strong spin–orbit coupling and magnetic exchange interactions. Here, Ru‐doping‐enhanced AHE in La2/3Sr1/3Mn1−xRuxO3 epitaxial films is exploited. As the B‐site Ru doping level increases up to 20%, the anomalous Hall resistivity at room temperature can be enhanced from nΩ cm to µΩ cm scale. Ru doping leads to strong competition between the ferromagnetic double‐exchange interaction and the antiferromagnetic superexchange interaction. The resultant spin frustration and spin‐glass state facilitate a strong skew‐scattering process, thus significantly enhancing the extrinsic AHE. The findings can pave a feasible approach for boosting the controllability and reliability of oxide‐based spintronic devices.

Hafnium‐based binary oxides have attracted considerable attention due to their robust ferroelectricity at the nanoscale and compatibility with silicon‐based electronic technologies. To further promote the potential of Hafnium oxides for practical device applications, it is essential to effectively harness the interplay between structural symmetry, domain configuration, and ferroelectricity. Here, using Hf0.5Zr0.5O2/La0.67Sr0.33MnO3 (HZO/LSMO) heterostructures as a model system, the anisotropic strain‐mediated symmetry engineering and ferroelectricity enhancement are systematically investigated. By growing the heterostructures on (110)‐oriented perovskite substrates, considerable anisotropic strain is imposed on the LSMO bottom electrodes. Such an anisotropically‐strained LSMO layer acts as a structural template and effectively tune the structural symmetry, polar/non‐polar phase ratio, and ferroelectricity of the HZO top layer. Specifically, the anisotropic tensile strain stabilizes the ferroelectric rhombohedral and orthorhombic phases, thus enhancing the remnant polarization (Pr) up to 22 µC cm−2. In contrast, the anisotropic compressive strain facilitates the formation of non‐ferroelectric tetragonal phases, leading to a suppressed Pr down to 8 µC cm−2. These findings provide a guideline for understanding and modulating the intrinsic structure‐ferroelectricity relationship of HZO through anisotropic strain‐mediated symmetry engineering, which may shed light on the development of hafnium‐oxide‐based electronic devices.