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Numerous emerging applications in modern society require humidity sensors that are not only sensitive and specific but also durable and intelligent. However, conventional humidity sensors do not have all of these simultaneously because they require very different or even contradictory design principles. Here, inspired by camel noses, we develop a porous zwitterionic capacitive humidity sensor. Relying on the synergistic effect of a porous structure and good chemical and thermal stabilities of hygroscopic zwitterions, this sensor simultaneously exhibits high sensitivity, discriminability, excellent durability, and, in particular, the highest respond speed among reported capacitive humidity sensors, with demonstrated applications in the fast discrimination between fresh, stale, and dry leaves, high-resolution touchless human-machine interactive input devices, and the real-time monitoring humidity level of a hot industrial exhaust. More importantly, this sensor exhibits typical synapse behaviors such as paired-pulse facilitation due to the strong binding interactions between water and zwitterions. This leads to learning and forgetting features with a tunable memory, thus giving the sensor artificial intelligence and enabling the location of water sources. This work offers a general design principle expected to be applied to develop other high-performance biochemical sensors and the nextgeneration intelligent sensors with much broader applications.

Nonvolatile transistor memories (NVTMs) are fabricated based on a polymer blend dielectric containing poly(pentafluorophenyl acrylate) (pPFPA) and branched-poly-(ethylene imine) (bPEI). Detailed studies reveal this dielectric not only exhibits a high dielectric constant (k = 285 at 20 Hz), apparent polarization hysteresis, and robust mechanical properties but also endows a transistor (PBTTT-C14 as semiconductor) with ultrahigh mobilities (7.5 cm 2 V −1 s −1 ) and on/off ratios (10 7 ). By virtue of this, NVTMs possessing an eight-level storage capability at low operating gate voltages are demonstrated, with good data retention and endurance of over 10 5 s and 100 cycles, respectively. More importantly, the drain current can also be well controlled by the gate voltage pulse width, leading to NVTMs with twodimensional (voltage and time) storage capability. Further, the application of the NVTMs to data recording, encryption, and protection is demonstrated, with a desirable security feature, opening the door to NVTMs with higher performance.