| Graphdiyne(GDY),a new member of the carbon nanomaterials,is only composed of sp and sp~2 hybridized carbon atoms and the adjacent benzene rings are connecting by diacetylenic linkages in 2D planar network,which endow GDY with largeπ-conjugated system,excellent chemical stability and semiconductor properties.GDY was first synthesized in 2010 and has attracted much attention in terms of synthesis,characterization and application.Based on the distinct properties such as unique electronic structure,high carrier mobility and uniformly distributed pores,GDY has exhibited promising potential in practical applications,for instance electronic devices,catalysis,energy storage and conversion and water-oil separation.In addition,many researchers have introduced heteroatoms or functional groups into the 2D network of GDY through reasonable molecular design to prepare new type graphyne in order to explore unique properties and promote the development of graphyne famliy.As a semiconductor with band gap,GDY shows enormous potential in optoelectronic devices,and the development of two-dimensional GDY films not only simplifies the manufacturing process of the devices,but also benitfits to the functional applications in flexible and wearable devices,as well as further explores the stacking mode of GDY on the scale of a nanometer and carrier transport properties.However,the GDY films obtained by current preparation methods have the problems of small size and difficulty in peeling off from substrates,as well as,the application of GDY films in the field of electronic devices still in the primary stage,such as non-volatile memristors.According to those problems,the details of this thesis are given as follows:(1)We developed a simple approach to fabricate large-area,homogeneous,free-standing GDY films at air/water interface,via catalytic homocoupling of hexaethynylbenzene(HEB)at ambient temperature.The high uniformity,large size and low surface roughness of the obtained GDY films can be easily transferred to arbitrary substrates for characterization and devices fabrication.Based on the intrinsic porosity and uniformity of this ultrathin GDY film(about 7 nm),we fabricated memristors with Ag/GDY film/ITO vertical sandwich structure for the first time which exhibited steady nonvolatile and rewritable resistance switching behavior with excellent data retention capability(～10~3 s)and high on/off ratio(>10~3).Then we discussed the conduction and switching mechanism of memristors.This study exhibited an effective strategy to prepare GDY ultrathin films,which to a large extent simplified the typical complex fabrication processes of carbon-based memristors.The results may pave the way to the application of GDY in flexible and wearable all-carbon information storage electronics.(2)A fully conjugated 2D GDY films containing a porphyrin unit is frabricated by alkyne–alkyne homocoupling reaction on the surface of Cu(111)substrate using5,10,15,20-(tetra-4-ethynylphenyl)porphyrin(TEPP)as monomer.A large-area,free-standing and uniform films with good mechanical stability can be obtained through control the dropping speed of TEPP carefully during solid-liquid interfacial synthesis process.Then we frabricated memristors based on the films using Cu as the bottom electrodes and Au as the top electrodes.This device exhibited a write once read many(WORM)resistance switching behaviors with excellent data retention capability(～10~5 s),high on/off ratio(>10~4)and 87%of the devices possess low threshold voltage(0.4-0.5 V).This work developed a new way for the preparation of TEPP-GDY films,which may open a door of graphyne materails for low power consumption and high-diensity strorage devices application. |
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