SEMINAR 

Key Lab of Inorganic Functional Materials and Devices, CAS

中国科学院无机功能材料与器件重点实验室

Selective detection of hydrogen and hydrogen containing gases with metal oxide gas sensor operating in non-stationary thermal regime

Professor Alexey Vasiliev 

Kurchatov complex of chemical and physical technology

NRC Kurchatov Institute 

时间：2019年4月25日（星期四）上午10: 00

地点： 嘉定园区F7第二会议室 

联系人：刘志甫（69906595） 

　　报告摘要： 

　　The main disadvantage of metal oxide (MOX) gas sensors is their insufficient selectivity leading to the dominating application for the quantitative analysis of one-component systems with certain composition, for example, CH₄-air or H₂-air. The application of non-stationary working regimes (modulation of gas flow, temperature, switch on-off of any chemical converter, etc.) increases the selectivity, because of an increase in the information about the nature of the analite.  This improvement of selectivity is possible due to the revealing of the kinetics of the chemisorption of the analite and of the product desorption, the analite interaction with the surface located oxygen anions, etc.  

　　The application of temperature modulation in MOX sensors can solve the selectivity problem, only if some important conditions are met. It is necessary (1) to use gas sensitive layer composition leading to different kinetics of the chemisorption and reaction with surface for different gas analites;  (2) to find appropriate temperature regime giving extreme in the curve representing electrical resistance as a function of time; (3) to develop the algorithms of the treatment of multi-dimensional data arrays, because the application of non-stationary regime of the sensors operation leads to very significant increase in information volume about gas medium to be analyzed. Gas sensing materials based on Pd decorated SnO₂ have at certain temperature regimes characteristic extrema at the curves representing the resistance of the sensing layer as a function of time (and, therefore, temperature). These extrema are well pronounced at the detection of hydrogen and gases, which can be dehydrogenized at the interaction with the sensing layer (ethanol, acetone, H₂S, etc).  The multi-dimensional data arrays were treated using Principle Component algorithm shows the possibility to determine both qualitative and quantitative composition of gas mixtures in both one and two component mixtures. 

　　报告人简介： 

亚力山克斯.瓦西列夫（Alexey Vasiliev），博士，俄罗斯国家研究中心库恰托夫研究所 应用化学物理中心 教授，实验室负责人。1980年大学毕业于莫斯科物理和技术研究所分子和化学物理系；1986年毕业于库恰托夫原子能研究所，获副博士学位；2004年于莫斯科电力工程研究所（莫斯科技术大学）获科学博士学位。1980-2004年在俄罗斯国家研究中心库恰托夫研究所分子物理中心工作，先后任研究员、高级研究员；2004-2009年于西班牙University Rovira I Virgili电子工程和汽车系任“Ramon i Caja Professor”；2009年至今任现职。亚力山克斯.瓦西列夫博士曾在美国福特汽车公司和密歇根大学（1996年）、德国Humboldt University的瓦特-能斯特物理化学研究所（1995-2004年，访问教授，多次）、意大利Instituto Yrentino di Cultura微电子系（1998-2007年，客座研究员，多次）、意大利University of Trento电子和通信系（1999-2004年，访问教授，多次）、芬兰University of Oulu（2011年）等进行访问或进行合作研究。曾获前苏联国家青年科学家奖（USSR State Prize）（1986年）、库恰托夫奖（Kurchatov Prime）（2000年）。亚力山克斯.瓦西列夫教授是含氟气体微集成传感器领域的专家，他长期致力于集成气体传感器、气体敏感机理的研究，在气敏响应动力学、MEIS型集成传感器、MEMS集成传感器等方面都做出了有独创性的工作。已发表论文300余篇，申请发明专利10余项。是“Eurosensors”系列会议的“Steering committee”成员、俄罗斯科学院分析化学委员会（Analytical Chemistry Council）成员。