▎ 摘　　要

NOVELTY - A diarylethene compound (I), (II), (III) or (IV), is new. USE - New diarylethene compound is used for forming transistor e.g. flexible non-losable organic memory transistor devices and light-responsive organic transistor devices, and diarylethene-graphene molecular junction device used in reversible light-controlled molecular switch device, reversible electronically controlled molecular switch device and reversible temperature-controlled molecular switch device (all claimed). ADVANTAGE - The compound (I), (II), (III) or (IV) provides molecular switch device with high reversibility and reproducibility, light-controlled switching cycles of more than 104, and electrically-controlled switching cycles of 105 or more. The reversible molecular switch device remains stable within a period of more than one year. DETAILED DESCRIPTION - A diarylethene compound of formula (I), (II), (III) or (IV), preferably of formula (I-1), (I-2), (II-1), (II-2), (III-1) or (III-2), is new. Cn=3-4C linear alkylene, or alkyl which is optionally substituted with halo. INDEPENDENT CLAIMS are included for the following: (1) diarylethene-graphene molecular junction device, which comprises the compound chosen from (I), (II), (III) and (IV), which is covalently bonded to a gap of a two-dimensional single-layer graphene having a nanogap array through an amide covalent bond; (2) reversible light-controlled molecular switch device, comprises the diarylethene-graphene molecular junction device. The reversible light-controlled molecular switch device is in a highly conductive state under the irradiation of UV-light and low conductive state under the irradiation of visible light. The reversible light-controlled molecular switch device further comprises a visible light generating device and UV-light generating device for irradiating the visible light or UV-light; (3) reversible electronically controlled molecular switch device, which has the diarylethene-molecular graphene junction device and a voltage generating device connected to both ends of the molecular junction device. The voltage generating device is used for providing a voltage of 0.2-1.5 V or (-0.2)-(-1.50) V to the terminals of the molecular junction device. When the voltage generating device provides -1.5 V or (-0.2)-(-1.50) V to both ends of the molecular junction device, the reversible electronically controlled molecular switch device comprising the diarylethene compound (I) or (II), preferably compound (I-1) or (I-2) exhibits a high-conductivity and a low-conductivity random switching state at 160-220K. When the reversible electronically controlled molecular switch device comprises the diarylethene compound chosen from (I), (II), (III) or (IV), preferably compound (II-1), (II-2), (III-1), or (III-2), the reversible electronically controlled molecular switch device exhibits a state of high-conductivity and a low-conductivity random switching state at 100-300 K. When the voltage generating device provides a voltage of (-0.9)-(0.9) V or (1.5)-(-1.5) V, the reversible electronically controlled molecular switch device comprising the diarylethene compounds (I-1) or (I-2) exhibits a low conductive state of (-0.9)-(0.9) V and a high conductive state of (1.5)-(-1.5) V at 160-220 K. When the reversible electronically controlled molecular switch device comprises the diarylethene compound (II-1), (II-2), (III-1) or (III-2), the reversible electronically controlled molecular switch device exhibits a low conductive state of (-0.9)-(0.9) V and a high conductive state of (1.5)-(-1.5) V at 100-300 K; (4) reversible temperature-controlled molecular switch device, which has the diarylethene-graphene molecular junction device. When the reversible temperature-controlled molecular switch device comprises the diarylethene compound (I-1) or (I-2), the reversible temperature-controlled molecular switch device exhibits a low conductivity state at less than 160 K and a high conductivity state at more than 220 K. When the reversible temperature-controlled molecular switch device comprises the compound (II-1), (II-2), (III-1) or (III-2), the reversible temperature controlled molecular switch devices exhibits low conductivity at temperatures less than 100 K and a high conductivity at temperatures more than 300 K. The reversible temperature-controlled molecular switch device further has a temperature control device for providing a temperature of 160 K or more to the temperature-controlled molecular switch device or providing the temperature-controlled molecular switch device a temperature of less than 100K or greater than 300 K temperature; (5) transistor device, which has a semiconductor layer assembled between a dielectric layer and a semiconductor layer of an organic field effect transistor, and the compound (I) between the electrode of the organic field effect transistor and the semiconductor layer; (6) azobenzene compound of formula (IV-1) or (IV-2); and (7) spiropyran compound of formula (V-1) or (V-2).