| In recent years,two-dimensional（2D）materials have become a hot research object in the field of materials science due to their unique layered structure,excellent photoelectric properties and wide applications in catalysis,energy storage and other fields.However,it’s a great challenge to prepare large-scale 2D thin film in a facile way with current strategies.Therefore,it is necessary to further explore new methods to fabricate 2D films meet the challenge.Here,we developed several interfacial techniques for synthesis of2D films and explored their applications in electrocatalytic oxygen reduction reaction（ORR）.The specific research contents are summarized as follows:1.Nitrogen-doped graphdiyne（N-GDY）thin film was synthesized by a’bottom-up’strategy using nitrogen-containing alkynes as monomers.In traditional liquid/liquid or air/liquid interfacial method,the size of film was restricted by the contact area,leading to limited yield.In order to solve this problem,we proposed a new synthesis method based on continuous stirring.By optimizing water/oil vol ume ratio,the monomer droplets solved in the oil phase can fully mix with the catalyst solved in the water phase through simple mechanical stirring,which can greatly increase the contact area in the limited space,as a result,high quality and large-scale preparation of N-GDY film can be prepared in this way.The thickness of N-GDY film formed on the reaction interface is about 10 nm.This method can fabricate thin N-GDY film with high yield with low energy consumption.2.Besides,Co/N-GDY composite catalyst was obtained by loading uniformly distributed Co nanoparticles on N-GDY by a simple mixing method using the synergistic anchoring effect of alkyne bonds and nitrogen atoms.A series of oxygen reduction performance tests were carried out.The catalyst has excellent ORR catalytic performances.Under the condition of 0.1 M KOH,its starting potential can reach 0.84 V（relative to the reversible hydrogen electrode（RHE））,and the highest limiting current density was about 3.91 m A cm-2.In addition,the catalyst showed a minimum Tafel slope of 88.9 m V dec-1,indicating high catalytic efficiency.To sum up,the Co/N-GDY hybrid prepared here has the advantages of low cost and high ORR efficiency.Meanwhile,it exhibited better methanol resista nce and long-term stability compared with commercial catalyst Co/N-GDY,providing new thoughts in synthesis of composite catalyst and applications beyond ORR.3.In addition,diacetylene monomer strip arrays were fabricated by liquid-bridge induced a controllable dewetting strategy.The monomers were further self-assembled induced by hydrogen bonds.At last,For the controlled dewetting method,hydrophilic silicon template wit h microarrays was employed,by adding monomer solution,liquid film can be formed on the substrate.when the liquid film was broken to form a liquid bridge between the template and the template thanks to the“pinning”effects of the silicon pillars.Finally,the ordered arrangement of diacetylene molecules was achieved by controlling solvent evaporation and confined assembly within the liquid bridge.The morphology of the prepared monomer array was characterized by optical microscope（OM）,scanning electron microscope（SEM）and atomic force microscope（AFM）.The experimental results showed that patterned single crystal array of diacetylene monomer molecules can be prepared by this method.The surface of the strip array was flat and the thickness was about 20 nm.The spacing between adjacent strips can be adjusted by regulating template parameters.Polydiacetylene arrays were obtained by further in-situ polymerization under UV irradiation.In addition,the composition of the arrays before and after polymerizat ion was characterized by Raman spectroscopy.Due to the fully conjugated linear structures polydiacetylene,the prepared polydiacetylene arrays can be employed as organic field effect transistors with high field effect mobility,moreover,this method showe d great potential in constructing diverse optical and electrical devices. |
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