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5-7 mm in length were used. The pressure was measured using the pressure dependence of the superconducting transition temperature of a built-in pressure sensor made of high-purity tin [23]. Experimental data were corrected for diamagnetism using Pascal's constants.Visible Absorption Spectroscopy under Hydrostatic Pressure: Full absorption spectra were recorded between 450 and 750 nm by using a Carl Zeiss PGS-2 spectrometer. The hydrostatic-pressure cell made of hardened beryllium bronze with NaCl as the pressure-transmitting medium operated in the pressure range 10 5 Pa < P < 3 GPa (accuracy ≈ ± 0.1 GPa). The pressure was measured using the pressure dependence of ruby [24].

In this paper, (1) a simple and controllable method to synthesize single crystalline nanoribbons of CuTCNQ in a large area was demonstrated by using a physical and chemical vapor combined deposition technique. (2) Nanoribbons synthesized by this method were identified to belong to phase I. (3) Devices and device arrays of nanoribbons were in situ fabricated by this method using gap electrodes and gap electrode arrays. (4) Current-voltage characteristics of crystalline devices and device arrays of nanoribbons exhibited semiconductor properties, and this conclusion was further confirmed by the results of devices based on an individual nanoribbon or microribbon of CuTCNQ (phase I). The controllable synthesis of nanoribbons for the in situ fabrication of crystalline nanodevices and device arrays will be attractive for nanoelectronics. Moreover, semiconductor current-voltage characteristics of the nanoribbons will be beneficial to the understanding of CuTCNQ.

The self-assembly behaviors and charge transport properties of cruciforms with anthracene as one axis were studied. By changing one axis of these cruciforms, the assembly morphologies of single crystal micro/nanostructures transferred from one dimension to three dimensions. This morphology transformation was controlled by the intermolecular interactions of cruciforms, which was proved by single crystal X-ray diffraction results and presented a facile way to synthesize different dimensional micro/nanostructures through molecular design. Field-effect transistors based on individual single crystal micro/nanostructure exhibited high performance. These results suggested the potential applications of cruciform in organic electronics.

The development of van der Waals heterostructures in 2D materials systems has attracted considerable interests for exploring new insights of (opto‐) electrical characteristics, device physics, and novel functional applications. Utilizing organic molecular material with strong electron withdrawing ability, charge transfer van der Waals interfaces are formed between 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane (F4TCNQ) and MoS2, via which the modulation of the onset voltages and optimization of subthreshold swing values in MoS2‐based field effect transistors are realized. Charge transfer process and its functionality mechanisms are further verified and investigated with first‐principles calculation, scanning Kelvin probe microscope characterization, and temperature‐dependent electrical characterization. With the charge transfer effect between reducing gas molecules and F4TCNQ, NH3 gas sensor is proposed and fabricated with the sensitivity reaching higher than 1000% at 100 ppm, much more outstanding performance than those of any reported MoS2‐based NH3 gas sensors. The F4TCNQ‐MoS2 hybrid strategy might open up a pathway for tuning and optimizing the electrical properties, in addition to novel functional units designing and fabrications in electric devices based on low‐dimensional semiconducting systems.

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Resistive random access memory (RRAM) has attracted significant interest for next-generation nonvolatile memory applications. However, it is somehow difficult to design a high speed RRAM device with enhanced data reliability. This paper deals with the improvement of high speed durable switching in nanocrystals based RRAM (NC-RRAM) devices. The high performance RRAM devices were prepared by incorporating the NCs into the HfOx oxide layer. As compared to the without (w/o) NC devices, the NC-RRAM devices are capable to execute uniform switching with higher set speed of 100 ns and reset speed of 150 ns, longer retention time and higher endurance of 108 cycles at 85 °C. The possible switching mechanism is due to the formation and rupture of the conductive filaments (CFs) inside the oxide film. The improvement of the NC-RRAM devices is due to the enhanced electric field intensity on the surface of the NCs, which can effectively facilitate the formation and rupture of the CFs.