An artificial synaptic device that can provide color discrimination, image storage, and image recognition is highly required to mimic the human vision for biological robots. All-inorganic halide perovskites have attracted extensive attention for the reason of their high stability and favorable photoelectric properties. In this study, a light-stimulated synaptic phototransistor based on a CsPbBr 3 /organic semiconductor hybrid film is reported. The fabricated CsPbBr 3 film exhibits an island structure, which reduces the hysteresis effectively and at the same time achieves a high specific detectivity of up to 2 × 10 15 Jones. The decay of the photocurrent can be delayed by changing the gate bias, which is essential for achieving high-performance light-stimulated synaptic devices. Due to the outstanding detectivity of the device, the obvious synaptic functions can be observed when triggered by a light signal with a power of 1.6 nW that is much weaker than previous most perovskite-based hybrid synaptic phototransistors under a low operating voltage of −1 V. The electrical power consumption of the device could be as low as 0.076 pJ when the power of light spike was 7.36 nW. Taking into account this characterization, with changing of light intensity or wavelength, the contrast of the image was enlarged, which can further promote the image recognition accuracy. More significantly, this CsPbBr 3 /TIPS hybrid film can be fabricated by facile and low-cost solution processes. This study indicates the great potential of solution-processed perovskite-based light-stimulated synapses for future artificial visual systems.

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Molybdenum disulfide (MoS2), which is belonged to two-dimensional transition metal chalcogenides, has been considered to have great lithium/sodium storage potential. However, the poor conductivity, unsatisfied mechanical stability as well...

Sensory adaptation is an essential function for humans to live on the earth. Herein, a hybrid synaptic phototransistor based on the mixed-halide perovskite/organic semiconductor film is reported. This hybrid phototransistor achieves photosensitive performance including a high photoresponsivity over 4 × 103 A/W and an excellent specific detectivity of 2.8 × 1016 Jones. Due to the photoinduced halide-ion segregation of the mixed-halide perovskites and their slow recovery properties, the experience-history-dependent sensory adaptation behavior can be mimicked. Moreover, the light pulse width, intensity, light wavelength, and gate bias can be used to regulate the adaptation processes to improve its adaptability and perceptibility in different environments. The CsPbBr x I3–x /organic semiconductor hybrid films produced by spin coating are beneficial to large-scale fabrication. This study fabricates a novel solution-processable light-stimulated synapse based on inorganic perovskites for mimicking the human sensory adaptation that makes it possible to approach artificial neural sensory systems.

In this work, a novel hierarchical tubular structure (SnO 2 @NC@MoS 2 / C) has been designed and synthesized using MnO x nanowires as a sacrificing template for the hollow tube and successively wrapping a SnO 2 layer, nitrogen-doped carbon (NC) layer, and ultrathin MoS 2 nanosheets incorporating into a carbon layer. In such a particular structure, the conductivity of SnO 2 and MoS 2 has been obviously improved, and the large volume change caused by the lithium/sodium-ion (Li + /Na + ) intercalation/ deintercalation has also been effectively alleviated. Especially, due to the expansion of the spacing between MoS 2 layers caused by the outermost carbon derived from glucose, the shuttling of Li + /Na + between the layers becomes easier. Thanks to the advantages mentioned above, hierarchical hollow nanostructures feature the synergistic effects of different components, the SnO 2 @NC@MoS 2 /C nanocomposite displays an exceptional discharge capacity (980.9 mAh g −1 at 0.2 Ag −1 ) and long cycle stability (750 mAh g −1 at 1 Ag −1 for 450 cycles) when applied in lithium-ion batteries. Even at 2, 5, and 10 Ag −1 , the specific capacities still reach up to 672.7, 630.1, and 565 mAh g −1 after 500 cycles, respectively, which delivers an ultrastable highrate cycle performance. Meanwhile, it also achieves eminent capacity (479.3 mAh g −1 at 0.2 Ag −1 over 150 cycles), small capacity attenuation rate (0.06% per cycle after 2000 cycles at 1 Ag −1 ), and superior rate capacity (818.5, 691.6, 577.6, 506.3, 442.4, and 348.2 mAh g −1 at 0.1, 0.2, 0.5, 1, 2, and 5 Ag −1 , respectively) when the composite used for sodium-ion batteries.