Adaptation is the most common and basic feature of living systems, which gives species or individuals a survival advantage. In particular, visual adaptation can enable organisms with a clearer understanding of the real world, thereby avoiding potential harm, which is vital for the life activities of organisms. However, current adaptive devices based on logic circuits are still facing the great challenges for large-scale integration and limited bionic functions. Therefore, the hardware impleofmentation of biological visual adaptability through the emerging photoelectric devices may provide a great opportunity for the bionic systems facing complex environments. Here, a novel adaptive device based on a mixed-dimensional van der Waals heterostructure is fabricated by using a gate-modulated 0D-CsPbBr 3-quantum-dots/2D-MoS 2 heterostructure. The device has superior electric adaptabilities and excellent optical absorption abilities owing to its special energy-band structure. The key characteristics of biological adaptation, such as accuracy, sensitivity, inactivation, and desensitization behaviors, are successfully emulated in the device based on the unique trapping-detrapping mechanism. Most importantly, with a photoelectric synergy approach, the fascinating visual adaptation function based on an environment-adjustable threshold is finally demonstrated. These results indicate that the proposed device may be very promising for the future applications of artificial visual systems and intelligent bionic robots.

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The widespread implementation and rapid growing development of emerging sensor systems has posed stringent performance requirements on high‐performance photoelectric detection. Therefore, researchers are committed to finding a new kind of semiconductors with faster response time, higher sensitivity, and better stability. Nowadays, anisotropic 2D materials have drawn great attentions in photoelectric detection due to their unique crystal structures and optical absorption properties. These properties make them possible to detect a wide spectrum from ultraviolet to infrared, which provides a good choice for photoelectric detection under complex conditions. Herein, the various anisotropic 2D materials with intriguing physical properties and their device applications for optoelectronic detection are reviewed.

In neural system, the nociceptor normally exhibits important characteristics such as pain threshold, memory of prior injury, and sensitization/desensitization. [7,8] Pain perception usually includes nociceptive sensation, pain intensity, pain unpleasantness, and cognitive behavior, which is an unconditional driving force for the behavioral response to stop pain. [9] Humans may adopt pain-related fears, psychological distress, and other physical responses to avoid the potential dangers. Therefore, the exploration of novel artificial nociceptors is of great importance for nextgeneration intelligence equipment. In the past few years, nociceptor have been emulated by the emerging devices with two-terminal or three-terminal structures. [10][11][12] Although these works are very promising, this artificial nociceptor equipment usually receive electric signals or light signals caused by damaging forms of energy from the environment. At present, an artificial nociceptor with strong sensitization characteristics is still lacking.Interestingly, several reports have revealed that the pain conditioning phenomenon triggered by Pavlovian training is the basis of more advanced pain-perceptual behaviors, including how the brain learns, subsequently detects, and responds to threats. [13,14] Moreover, Pavlovian fear conditioning is an important mechanism for learning from the pain stimulus and protecting themselves from the outside dangers. [15][16][17][18] Therefore, the realization of a neuromorphic device with the strong pain-to-fear perceptual abilities by Pavlov's learning rule may open a new avenue in the emerging bionic applications. However, such a device still remains to be explored till now.In this paper, a pain-to-fear perceptual device can be successfully demonstrated using organic-inorganic hybrid electrolyte-gated MoS 2 transistor. Based on the unique ion migration mechanism in polymer electrolyte, our bionic transistor can realize several key features of pain perception, such as pain threshold, sensitization, desensitization, and so on. Moreover, a clear transition from pain-to-fear recognition by Pavlovian training can be finally achieved. Our organic-inorganic hybrid transistor cannot only achieve the classical pain perception but also exhibit a recognition transition from pain to fear. Consequently, this designed pain-perceptual device may be very promising for the next generation of intelligence cognitive electronics.The pain perception system is of great importance for the human body to perceive noxious stimuli in external environment and make an appropriate reaction. Therefore, the hardware realization of nociceptors using emerging solid-state device is of great importance toward the next-generation intelligent electronic devices. However, at present, the pain recognition with threshold regulation is still very lacking by using the solid-state device. Herein, a novel pain-perceptual device based on organic-inorganic hybrid MoS 2 transistor is fabricated by using polyvinyl alcohol-based electrolyte. The key char...

Two-dimensional (2D) MoS2 is regarded as one of the most promising channel materials for field-effect transistors (FETs) due to its thickness-dependent bandgap and high air-stability. However, current MoS2 FETs generally...