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For the progress of artificial neural networks, the imitation of multiple biological functions is indispensable for processing more tasks in a complex working environment. Memristors, which possess these advantages such as uniformity, high switching speed, and smaller device scale, are the better candidates compared to conventional complementary metal–oxide–semiconductor (CMOS) technology in artificial neural networks. In this work, an Ag/ZrOx/Pt threshold switching memristor (TSM) is designed to overcome the drawback of the large variation in the non‐volatile filament type memristor. The cycle‐to‐cycle and device‐to‐device variations are 5.6% and 4.9%. This device has mimicked the "nociceptive threshold," "relaxation," "no adaptation," and "sensitization" features for the nociceptor which can prevent the artificial intelligence system from dangers in the external environment. Additionally, with the change in the strength of the external stimulus, the artificial neuron is also built by emulating "all‐or‐nothing," "threshold‐driven‐spiking," and "strength‐modulated" characteristics. The proposed threshold‐switching memristor allows the simultaneous emulation of the biological nociceptor and leaky integrate‐and‐fire neuron for the first time, which represents an advance in the bioinspired technology adopted in future artificial neural networks and humanoid robots. [ABSTRACT FROM AUTHOR]

Preparation of reliable, stable, and highly responsive gas-sensing devices for the detection of acetone has been considered to be a key issue for the development of accurate disease diagnosis systems via exhaled breath. In this paper, novel CeO 2 nanodot-decorated WO 3 nanowires are successfully synthesized through a sequential hydrothermal and thermolysis process. Such CeO 2 nanodot-decorated WO 3 nanowires exhibited a remarkable enhancement in acetone-sensing performance based on a miniaturized micro-electromechanical system device, which affords high response ( S = 1.30-500 ppb, 1.62-2.5 ppm), low detection limit (500 ppb), and superior selectivity toward acetone. The improved performance of the acetone sensor is likely to be originated from the fast carrier transportation of WO 3 nanowires, the formation of WO 3 -CeO 2 heterojunctions, and the existence of large amounts of oxygen vacancies in CeO 2 . The improved reaction thermodynamics and sensing mechanisms have also been revealed by the specific band alignment and X-ray photoelectron spectroscopy analysis.

Atomic scale control of the thickness of thin film makes atomic layer deposition highly advantageous in the preparation of high quality super-lattices. However, precisely controlling the film chemical stoichiometry is very challenging. In this study, we deposited SiO x film with different stoichiometry by plasma enhanced atomic layer deposition. After reviewing various deposition parameters like temperature, precursor pulse time, and gas flow, the silicon dioxides of stoichiometric (SiO₂) and non-stoichiometric (SiO 1.8 and SiO 1.6 ) were successfully fabricated. X-ray photo-electron spectroscopy was first employed to analyze the element content and chemical bonding energy of these films. Then the morphology, structure, composition, and optical characteristics of SiO x film were systematically studied through atomic force microscope, transmission electron microscopy, X-ray reflection, and spectroscopic ellipsometry. The experimental results indicate that both the mass density and refractive index of SiO 1.8 and SiO 1.6 are less than SiO₂ film. The energy band-gap is approved by spectroscopic ellipsometry data and X-ray photo-electron spectroscopy O 1s analysis. The results demonstrate that the energy band-gap decreases as the oxygen concentration decreases in SiO x film. After we obtained the Si-rich silicon oxide film deposition, the SiO 1.6 /SiO₂ super-lattices was fabricated and its photoluminescence (PL) property was characterized by PL spectra. The weak PL intensity gives us greater awareness that more research is needed in order to decrease the x of SiO x film to a larger extent through further optimizing plasma-enhanced atomic layer deposition processes, and hence improve the photoluminescence properties of SiO x /SiO₂ super-lattices.