The promotion of magnetic field on catalytic performance has attracted extensive attention for a long time, and substantial improvements have been achieved in some catalysis fields. However, because the Zeeman energy is several orders of magnitude weaker, magnetic field seems unable to alter the band structure and has a negligible effect on semiconductor photocatalytic performance, which makes this task a great challenge. On the other hand, the spin-related behavior usually plays an important role in determining catalytic performance. For example, in some molecular catalysis, such as photosystem II, ferromagnetic alignment of the active material results in spin-oriented electrons, which are selected and accumulated at the interface, leading to great promotion of the oxygen evolution reaction activity. Here, we propose a magnetoresistance-related strategy to boost the carrier transfer efficiency and apply it in α-FeO/reduced graphene oxide hybrid nanostructures (α-FeO/rGO) to improve the photocatalytic performance under magnetic field. We show that both the degradation rate constant and photocurrent density of α-FeO/rGO can be dramatically enhanced with the application of magnetic field, indicating the promotion of the photocatalytic performance.

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We explore the electronic structure of two-dimensional (2D) MnPSe3/MoS2 van der Waals (vdW) heterostructures based on density functional theory. A novel spin splitting at the valance band maximum of MnPSe3 appears in some specific stacking models due to Mn d orbital hybridization. The simultaneous spin and valley splitting can be achieved by interfacial coupling, which is attractive for manipulation of the valley and spin degrees of freedom. More importantly, due to the antiferromagnetic ordering of manganese, the opposite spin moments at K and K′ valleys can be observed by transforming configurations, which realizes the tunable spin splitting states. Our theoretical work opens up the opportunities of valley and spin related applications of MnPSe3/MoS2 vdW heterostructures and offers a practical avenue for exploring novel devices based on the spin and valley degrees of freedom.

We reported a novel BiOI/mesoporous TiO2 photoanode for solar cells, which was fabricated with BiOI attached onto a three-dimensional mesoporous TiO2 film by a chemical bath deposition (CBD) method. BiOI was revealed as an efficient and environmental friendly semiconductor sensitizer to make TiO2 respond to visible light. Based on this photoanode, mesoporous TiO2-based solar cell sensitized by BiOI exhibited promising photovoltaic performance. Meanwhile, the optimization of photovoltaic performance was also achieved by varying cycles of deposition immersions. The highest open circuit voltage and short circuit current of the solar cell can reach 0.5 V and 1.5 mA/cm(2), respectively.

The generation and manipulation of valley polarization in controllable ways are important for the valley-related physics and devices. In analogy to multiferroic materials with more than one ferromagnetic, ferroelectric, and ferroelastic orders, a new triferroic system with ferromagnetism, ferroelectricity, and ferrovalley is proposed, namely, the monolayer AgBiP2Se6/CrI3 van der Waals heterostructure. Using density functional theory, we further predict that the electrical control on the valley degree of freedom could be realized in this triferroic system. The mechanism of electrically controlled valley is elucidated as an intermediate coupling between lattice and ferroelectricity. The coupling of three ferroic orders in triferroic material paves the way for electrically controlled valleytronic devices.