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Voltage control of magnetic properties is a promising path to realize low-power spintronic devices and meets the requirements for quicker information processing speed and ongoing scale reduction. Hydrogen migration induced by voltage gating has been demonstrated to modify the intrinsic magnetic properties of materials by affecting the exchange interaction, electron occupancy, and magnetoelastic effect. Herein, the magnetic properties of a ferrimagnetic Gd29Fe71 film in an all-solid-state multilayer device, which is constructed using a GdOx electrolyte, can be reversibly modulated by voltage-controlled hydrogen migration. Polar MOKE results indicate that hydrogen intercalation/deintercalation can modulate the Gd29Fe71 film's degree of compensation and control the dominant magnetic sublattice. Furthermore, the polarity of the polar MOKE curves can be reversibly switched. As with the increase in hydrogen loading, the compensation point in the Gd29Fe71 film is approached, the density of magnetic domain nucleation sites decreases, and the magnetic domain structures transform from labyrinth domains to uniform large area domains. At the same time, a strong perpendicular magnetic anisotropy is developed. This work shows a possible pathway for reversible control of magnetism in spintronic devices. [ABSTRACT FROM AUTHOR]

As a new generation of core components for neuromorphic computing, optoelectronic synaptic devices have the advantages of high bandwidth and less energy consumption. They can combine the functions of visual sensing, signal processing, and memory in one device. Herein, an all‐solid‐state optoelectronic synaptic transistor using indium gallium zinc oxide (IGZO) as the channel and lanthanum fluoride (LaF3) as the gate dielectric is designed and fabricated. Its synaptic plasticity induced by electric and optical stimuli is investigated. LaF3 is a solid superionic conductor with plenty of mobile fluoride ions, which can be used to achieve a high on/off ratio of more than 105 and a low subthreshold swing less than 150 mV dec−1 in this novel synaptic transistor. Due to the ion‐trapping effect at the interface, synaptic plasticity can be achieved upon electrical stimulation. Synaptic plasticity by light pulse stimuli can also be accomplished with the assistance of the persistent photoconductivity effect in IGZO channel. Furthermore, it is found that the synaptic plasticity induced by light stimuli can be modulated by gate voltage. These results provide a new way to control synaptic function and extend the function of optoelectronic synaptic devices. [ABSTRACT FROM AUTHOR]

Halide perovskites (HPs) with marvelous optical and electrical properties are regarded as one of the competitive candidates for building next-generation photodetectors (PDs). However, combining their excellent properties with satisfactory long-term robustness is still challenging, ultimately limiting the practical applications of HP-based PDs. Herein, a high vacuum deposition system is employed to fabricate flexible self-powered PDs with a ZnO/CsPbBr 3 /γ-CuI structure, which shows excellent stability and outstanding performance in weak light detection. Benefiting from the improved crystallinity and optimized device structure, a high detectivity of 8.1 × 10 13 Jones and a rapid response speed (rise/decay time of 3.9/1.8 μs) are obtained in this self-powered device. Furthermore, the unencapsulated device exhibits intriguing environmental stability and mechanical flexibility. The photocurrent remains unchanged after 7000 s of continuous operation or 100 bending cycles. Furthermore, a 15 × 15 PD array is fabricated as an image sensor. A high contrast image of the target object can be obtained owing to the high sensitivity and uniformity of the self-powered PDs. These results demonstrate the feasibility and practicality of the ZnO/CsPbBr 3 /γ-CuI heterojunction for applications in weak light detection and image formation.

A hierarchical zeolitic imidazole framework (ZIF) combining a micropore with a mesoporous structure is desirable to enhance mass transport and gives rise to novel applications. Here, hierarchically porous graphene/ZIF-8 hybrid aerogel (GZAn) materials were successfully prepared by a two-step reduction strategy and a layer-by-layer assembly method. To avoid a tedious dry step and the use of an energy-consuming freeze-drying technology, a reduced graphene oxide hydrogel with different reduction degrees was chosen as a template to grow ZIF-8 crystals in situ. The parameter of density and elemental analysis was adopted to calculate the amount of ZIF-8 in GZAn materials for different assembly cycles. The distribution of micropores and mesopores of GZAn materials was controlled by changing the loading of ZIFs in GZAn materials. Furthermore, GZA8 materials showed enhanced CO 2 uptake capacity (0.99 mmol g -1 , 298 K, 1 bar) than pure ZIF-s crystals and pure graphene aerogels, showing an excellent synergistic effect of hierarchical pore structures. Meanwhile, with the increase of ZIF-8 loading, the mechanical robustness of GZAn was uplifted obviously. This work provides an efficient method to prepare hierarchically porous ZIFs-based materials with good CO 2 uptake capacity and tunable mechanical robustness.