A few-layer MoS2 photodetector driven by poly(vinylidene fluoride-trifluoroethylene) ferroelectrics is achieved. The detectivity and responsitivity are up to 2.2 × 10(12) Jones and 2570 A W(-1), respectively, at 635 nm with ZERO gate bias. E(g) of MoS2 is tuned by the ultrahigh electrostatic field from the ferroelectric polarization. The photoresponse wavelengths of the photodetector are extended into the near-infrared (0.85-1.55 μm).

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Van der Waals heterostructures based on 2D layered materials have received wide attention for their multiple applications in optoelectronic devices, such as solar cells, light-emitting devices, and photodiodes. In this work, high-performance photovoltaic photodetectors based on MoTe /MoS vertical heterojunctions are demonstrated by exfoliating-restacking approach. The fundamental electric properties and band structures of the junction are revealed and analyzed. It is shown that this kind of photodetectors can operate under zero bias with high on/off ratio (>10 ) and ultralow dark current (≈3 pA). Moreover, a fast response time of 60 µs and high photoresponsivity of 46 mA W are also attained at room temperature. The junctions based on 2D materials are expected to constitute the ultimate functional elements of nanoscale electronic and optoelectronic applications.

Sensitive photodetection is crucial for modern optoelectronic technology. Two-dimensional molybdenum disulfide (MoS2) with unique crystal structure, and extraordinary electrical and optical properties is a promising candidate for ultrasensitive photodetection. Previously reported methods to improve the performance of MoS2 photodetectors have focused on complex hybrid systems in which leakage paths and dark currents inevitably increase, thereby reducing the photodetectivity. Here, we report an ultrasensitive negative capacitance (NC) MoS2 phototransistor with a layer of ferroelectric hafnium zirconium oxide film in the gate dielectric stack. The prototype photodetectors demonstrate a hysteresis-free ultra-steep subthreshold slope of 17.64 mV/dec and ultrahigh photodetectivity of 4.75 × 1014 cm Hz1/2 W−1 at room temperature. The enhanced performance benefits from the combined action of the strong photogating effect induced by ferroelectric local electrostatic field and the voltage amplification based on ferroelectric NC effect. These results address the key challenges for MoS2 photodetectors and offer inspiration for the development of other optoelectronic devices.

Memristors with history‐dependent resistance are considered as artificial synapses and have potential in mimicking the massive parallelism and low‐power operation existing in the human brain. However, the state‐of‐the‐art memristors still suffer from excessive write noise, abrupt resistance variation, inherent stochasticity, poor endurance behavior, and costly energy consumption, which impedes massive neural architecture. A robust and low‐energy consumption organic three‐terminal memristor based on ferroelectric polymer gate insulator is demonstrated here. The conductance of this memristor can be precisely manipulated to vary between more than 1000 intermediate states with the highest OFF/ON ratio of ≈104. The quasicontinuous resistive switching in the MoS2 channel results from the ferroelectric domain dynamics as confirmed unambiguously by the in situ real‐time correlation between dynamic resistive switching and polarization change. Typical synaptic plasticity such as long‐term potentiation and depression (LTP/D) and spike‐timing dependent plasticity (STDP) are successfully simulated. In addition, the device is expected to experience 1 × 109 synaptic spikes with an ultralow energy consumption for each synaptic operation (less than 1 fJ, compatible with a bio‐synaptic event), which highlights its immense potential for the massive neural architecture in bioinspired networks.