Cu_(3)Mo_(2)O_(9)/MoO_(3)纳米复合材料制备及三甲胺气敏性能研究  

Research on synthesis of Cu_(3)Mo_(2)O_(9)/MoO_(3) nanocomposite and trimethylamine gas sensing properties

作　　者：毕文杰 杨爽 周静[1] 金伟[1] 陈文[1] Bi Wen-Jie;Yang Shuang;Zhou Jing;Jin Wei;Chen Wen(State Key Laboratory of Advanced Technology for Materials Synthesis and Processing,School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学材料科学与工程学院,材料复合新技术国家重点实验室,武汉430070

出　　处：《物理学报》2023年第16期267-277,共11页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:62171331);武汉理工大学三亚科教创新园开放基金(批准号:2020KF0026);湖北省自然科学基金(批准号:2020CFB188)资助的课题.

摘　　要：水产品的新鲜度极大地影响着人类的生命及身体健康,水产品在存放过程中会释放出以三甲胺为代表的胺类气体,通过检测这类气体的浓度可以监控水产品的新鲜度.本文以具有优良气体敏感性能的MoO_(3)纳米带作为基体,通过引入Cu_(3)Mo_(2)O_(9)纳米颗粒制备Cu_(3)Mo_(2)O_(9)/MoO_(3)复合材料,具有非常好的三甲胺气体敏感性能、快速响应/恢复时间及长期稳定性.结果表明,采用这种复合材料制备的气敏元件在50-240℃,质量分数为5×10^(-6)时对三甲胺气体的响应可达到Rair/Rgas=13.9,最小检测极限的体积分数为2×10^(-7).分布在MoO_(3)纳米带表面的Cu_(3)Mo_(2)O_(9)颗粒与基体形成异质结界面,利用Cu_(3)Mo_(2)O_(9)的强氧吸附能力与催化效应促进电子与空穴的分离,显著改善了复合材料的电子输运性能和气敏特性,为制备高性能MoO_(3)基气敏材料提供了新的策略.Aquatic products contain an incredibly high nutritional value for the human body and gradually become indispensable ingredients on the Chinese table.Trimethylamine(TMA)from the deterioration of aquatic products can serve as an indicator to measure fish freshness.It is a challenge to develop an instant,fast,convenient,and efficient gas sensor for fish freshness.In this study,a novel Cu_(3)Mo_(2)O_(9)/MoO_(3) composite gas sensing material is prepared by introducing Cu_(3)Mo_(2)O_(9) nanoparticles on the surface of MoO_(3) nanobelts.The results of SEM and TEM images show that the Cu_(3)Mo_(2)O_(9) nanoparticles are uniformly dispersed.Then,the TMA sensing performance of a resistance-type gas sensor based the prepared Cu_(3)Mo_(2)O_(9)/MoO_(3) composite is tested at optimal operating temperature(240℃).the results show that the sensor possesses good response(13.9)at low concentration(5×10^(-6)),with excellent low detection limit(2×10^(-7)).The response time is also significantly shortened.The high sensing performance of Cu_(3)Mo_(2)O_(9)/MoO_(3) composite is attributed to the heterojunction interface,which promotes the separation of electrons from holes through its strong oxygen adsorption and catalytic effect.This significantly improves the electron transport properties and gas sensing characteristics of the composite material.Electrons flow from MoO_(3) nanoribbons to Cu_(3)Mo_(2)O_(9),and the Fermi level reaches equilibrium.This process results in the formation of an electron loss layer underneath MoO_(3),and the charge transfer channel narrows,which is consistent with previous result.When trimethylamine dissociates on the nanoribbons to release electrons,the balance of the fermi lever is disrupted,and electrons flow from MoO_(3) to Cu_(3)Mo_(2)O_(9).As a result,the charge transfer channel becomes thinner,resulting in resistance modulation and increased sensitivity.In addition,the enhancement of trimethylamine sensing performance of Cu_(3)Mo_(2)O_(9)/MoO_(3) nanocomposite can be explained by the enhancement of

关 键 词：气体传感器 三甲胺 MoO_(3)纳米带 Cu_(3)Mo_(2)O_(9)颗粒 异质结 

分 类 号：TB332[一般工业技术—材料科学与工程]