Preparation Of ?-Graphyne And Research On Its Thermal And Gas Sensitive Properties

As a new two-dimensional carbon-based semiconductor materials,?-graphyne(?-GY)has the characteristics of low formation energy,high stability,large specific surface area,and rich pore structure.?-GY has broad application prospects in the fields of semiconductor devices and circuits.At present,the research work on?-GY is still in the exploratory stage,and there are few experimental preparation methods and specific device applications of?-GY.The thermal sensitivity and gas sensitivity of?-GY have not been experimentally studied before.In this paper,the constant temperature stirring method of?-GY has been proposed for the first time,and the thermal sensitivity and gas sensitive characteristics of?-GY have been explored through experiments.The research work in this paper will provide an experimental method reference for the future industrial preparation of?-GY,will open the door to the experimental research work of?-GY in the field of thermal and gas sensitivity,and will promote the wider application of?-GY in the field of semiconductor devices and circuits.The main research contents of this paper are:1.In the constant temperature stirring method of?-GY,the precursors used for preparation are C₆Br₆and CaC₂.The experimental preparation mechanism is to use the high-energy ethanol molecules in the constant temperature stirring process to promote the cross-coupling reaction of C₆Br₆and CaC₂.The main process of the experiment includes precursor pretreatment,constant temperature stirring preparation,calcination to remove impurities,washing to remove impurities,etc.Finally,the black fluffy powder has been obtained.After a series of characterization and analysis,it is determined that a high-purity?-GY polycrystal with two-dimensional structure has been prepared.2.This paper mainly analyzes the influence of factors such as experimental equipment,pretreatment process,impurity removal process,temperature during constant temperature stirring,and duration of constant temperature stirring on the preparation of?-GY.The reasonable settings and related parameters are determined as follows:calcination adopts a tubular atmosphere furnace with circulating nitrogen;in the short-time ball milling process of pretreatment,the precursors can be mixed with ball milling or separate ball milling;the impurity removal process is set to calcination and then washing;the constant temperature stirring temperature is set to 80?;the total duration of constant temperature stirring is not less than 23 h.3.The stability of?-GY prepared in this paper has been studied,and it is found that?-GY can guarantee the stability of?-GY structure and morphology within 200?under air atmosphere and 800?under inert gas atmosphere.Then the?-GY sensor is tested and analyzed for its thermal sensitivity,and it is found that?-GY exhibits the characteristics of a negative temperature coefficient thermistor,and its resistance decreases exponentially with the increase of temperature.The thermal constant B of the device is 2143.7,the time constant?is less than15 s,and the absolute value of the device aging rate after one hundred days is 0.069.4.This paper further conducts the NO₂gas sensitivity test and analysis on the?-GY sensor device.It is found that the adsorption capacity of?-GY for NO₂gas is stronger than the desorption capacity,and there is a baseline drift phenomenon in the dynamic response curve.Based on this phenomenon,the first derivative extreme value of the dynamic response curve has been selected as the detection index of NO₂gas concentration.Finally,this paper has determined that the working temperature of the?-GY gas sensor for NO₂gas is room temperature,the detection limit is about 2 ppm,the linear range is 10 ppm to 100 ppm,the gas selectivity is good,and the test repeatability and stability are relatively good.