电工技术学报
|
改性石墨烯基传感器对SF6分解组分H2S的吸附机理及检测特性研究
高新1,3, 李志慧1, 刘宇鹏1, 陈伟根2, 周渠1,2
1.西南大学工程技术学院 重庆 400716;
2.重庆大学输配电装备及系统安全与新技术国家重点实验室 重庆 400044;
3.四川省农业机械研究设计院 成都 610066
Study on Adsorption Mechanism and Detection Characteristics of Modified Graphene Sensors for SF6 Decomposed Component H2S
Gao Xin1,3, Li Zhihui1, Liu Yupeng1, Chen Weigen2, Zhou Qu1,2
1. College of Engineering and Technology Southwest University Chongqing 400716 China;
2. State Key Laboratory of Power Transmission Equipment & System Security and New Technology of Science and Technology Chongqing University Chongqing 400044 China;
3. Sichuan Agricultural Machinery Research and Design Institute Chengdu 610066 China
全文: PDF (2037 KB)  
输出: BibTeX | EndNote (RIS)      
摘要 作为SF6的重要分解组分,H2S能够有效反映SF6气体绝缘电气设备内部绝缘故障类型及程度。本文以H2S为目标检测气体,探究了改性石墨烯基传感器对H2S的吸附机理及检测特性。基于第一性原理建立了环氧基化石墨烯(G-O)、钯掺杂石墨烯(Pd-G)和环氧基与钯共掺杂石墨烯(Pd-G-O)改性模型和H2S吸附模型,从吸附能、态密度、轨道、脱吸附时间等多方面计算分析了G-O、Pd-G、Pd-G-O的改性机理与吸附机理,结果表明Pd-G-O对H2S表现出优异的吸附性能,吸附能达到-1.015 eV,为较强的化学吸附,且对应着强烈的电荷转移值0.281 e;制备了G-O、Pd-G、Pd-G-O传感材料及器件,基于微量气敏测试平台测试了改性石墨烯基传感器检测H2S的温度、浓度、响应恢复及稳定特性,其中Pd-G-O传感器对H2S表现出低工作温度(175℃)及快速响应优势。本文的仿真计算与气敏测试分析为研制检测SF6分解组分的低功耗、高灵敏度及快速响应传感器提供了理论基础与实验支撑。
服务
把本文推荐给朋友
加入我的书架
加入引用管理器
E-mail Alert
RSS
作者相关文章
高新
李志慧
刘宇鹏
陈伟根
周渠
关键词 ： 改性石墨烯,  SF6分解组分,  H2S检测吸附机理,  检测特性    
Abstract：H2S is one of the important decomposition products of SF6. It is the characteristic component in the event of high energy partial discharge or strong overheating fault, and can reflect the severity of the fault.The gas sensor method is a method using gas sensitive materials to detect the gas composition and concentration, and is often used to detect SF6 decomposed components.The gas sensing materials based on intrinsic graphene only show weak physical adsorption for most gases. Therefore, the sensing performance of graphene gas sensing materials and graphene gas sensors can be improved through various optimization methods such as doping, functionalization of functional groups, and composite.However, there are few studies on the properties of metal and functional group functionalized co-modified graphene in gas sensing detection at present.Based on this, three different modification methods including metal doping, functional group functionalization, doping and functional group functionalization co-modification were selected to improve the gas sensitivity of intrinsic graphene to H2S.
Firstly, the modification models of epoxy graphene (G-O), palladium doped graphene (Pd-G) and epoxy and palladium Co-doped graphene (Pd-G-O) are established, and the modification mechanism is analyzed. Secondly, the adsorption models of modified graphene for H2S are built, and the adsorption effect of H2S is analyzed from adsorption energy, density of state, orbitand desorption time.Thirdly, G-O, Pd-G and Pd-G-O sensing materials and planar gas sensors are prepared based on the oxidation-reduction method and drop coating method. The gas sensing performance for H2S are tested based on the micro gas sensing test platform.Finally, the response ability of the modified graphene sensors to H2S is evaluated from temperature characteristics, concentration characteristics, response-recovery characteristics and stability.
The simulation results of the modified models show that, the epoxy group effectively increases the energy gap of intrinsic graphene, from 0.049 eV to 0.218 eV. The doping of Pd introduces a new impurity level at the Fermi level, which effectively improves the charge transfer of intrinsic graphene. Through the co-doping of epoxy group and Pd, the energy gap reaches 0.214 eV, and the graphene system is more stable and the charge transfer ability is enhanced. In G-O adsorbing H2S system, the adsorption energy and charge transfer are -1.326 eV and 0.003 e, respectively. The adsorption energy is the largest, but the charge transfer capacity is extremely weak.In the system of H2S adsorbed on Pd-G, the charge transfer is 0.254 e, and the minimum adsorption energy is -0.897 eV. In Pd-G-O adsorbing H2S system, the co-modified graphene system shows the best adsorption performance, with the adsorption energy of -1.015 eV, which corresponds to a strong charge transfer value of 0.281 e. The results of gas sensitivity test show that, the optimum working temperature of G-O, Pd-G and Pd-G-O sensors is 225, 175 and 175 ℃ respectively. The lower detection limits for H2S are 6.9, 2.3, 0.5 μL/L. The response recovery time of Pd-G-O to 50 μL/L of H2S is 23/18 s. The response value is 10.02, which is the 1.818 and 1.538 times of that of G-O and Pd-G.
The following conclusions can be drawn from the analysis: 1) The stability and charge transfer ability of Pd-G-O system have been improved. The energy gap of intrinsic graphene is increased and metal energy level appears at Fermi energy level through the co-doping of epoxy group and Pd. 2) G-O, Pd-G, Pd-G-O improved the adsorption performance of intrinsic graphene for H2S. The Absolute value of adsorption energy is G-O>Pd-G-O>Pd-G; The charge transfer value is Pd-G-O>Pd-G>G-O. Among them, Pd-G-O shows great adsorption effect and charge transfer ability, attributing to the strong hybridization between the S 3p orbital and the Pd 4d orbital. 3) Pd-G-O sensor shows excellent gas sensing performance, and can be used as a promising gas sensor material for detecting H2S. Pd-G-O gas sensor shows the advantages of low operating temperature, low detection limit and high response value, suitable for the detection of trace H2S.
Key words： Modified graphene    SF6 decomposed component    H2S detection    adsorption mechanism    detection characteristics   
收稿日期: 2022-05-17     
PACS: TM855  
基金资助:国家自然科学基金资助项目（52077177）
通讯作者: 周 渠 男,1983年生,教授,博士生导师,研究方向为电力设备在线监测与故障诊断。E-mail：zhouqu@swu.edu.cn   
作者简介: 高 新 女,1998年生,硕士研究生,研究方向为电力设备在线监测与故障诊断。E-mail：1289547142@qq.com.
引用本文:   
高新, 李志慧, 刘宇鹏, 陈伟根, 周渠. 改性石墨烯基传感器对SF6分解组分H2S的吸附机理及检测特性研究[J]. 电工技术学报, 0, (): 19-19. Gao Xin, Li Zhihui, Liu Yupeng, Chen Weigen, Zhou Qu. Study on Adsorption Mechanism and Detection Characteristics of Modified Graphene Sensors for SF6 Decomposed Component H2S. Transactions of China Electrotechnical Society, 0, (): 19-19.
链接本文:  
https://dgjsxb.ces-transaction.com/CN/10.19595/j.cnki.1000-6753.tces.220842          https://dgjsxb.ces-transaction.com/CN/Y0/V/I/19