The innovative hydrogen sensor for cars
Experimental physicists from the Comenius University in Bratislava have developed an innovative semiconducting hydrogen detector with high sensitivity that works at room temperature. Its importance is demonstrated by the fact that hydrogen propulsion is in the viewfinder of the world’s major car companies and hydrogen is considered the fuel of the future. It is exactly this developed sensor that can increase security while reducing costs in this area, since there is the assumption that it has very low production costs.
The ability of the new hydrogen sensor to operate at normal (room) temperature together with its high sensitivity makes it widely applicable. In the framework of a long-term research since 2008, the team led by physicist prof. RNDr. Andrej Plecenik, DrSc., from the Department of Experimental Physics of the Faculty of Mathematics, Physics and Informatics of the Comenius University, overcame a serious deficiency in currently commonly produced semiconducting gas detectors, which is particularly their high working temperature. It usually ranges between 200°C and 400 °C, which amounts to a very low sensitivity at room temperature. The need for an elevated working temperature in the existing sensors significantly increases their energy consumption and therefore their long-term operation in small portable devices is not possible. It also affects their long-term stability and in some cases restricts their use in flammable or explosive environments.
“The newly developed sensor is based on a simple principle,” says prof. A. Plecenik from the Comenius University. “A measurement of the electrical resistance between two electrodes is made, between which there is a gas-sensitive fine layer with the thickness of several tens of nanometers. For a high sensitivity of the sensor even at room temperature, it is important that the width of the upper electrode is at the level of approximately 100 nanometers, or more precisely less. In such nanostructures, effects ongoing on a nano-scale will have considerable impact and it is thanks to this that the sensor has such exceptional qualities. Even though we presuppose that the sensor will be selectively sensitive particularly to hydrogen, it can be expected that after changing some parameters, it will be able to detect also other gases, e.g. methane in mines,“ explains physicist from the Comenius University.
The simplicity of the design of the new sensor from the Comenius University has also effect on its assumed very low production costs (basically few euros), while the production costs of currently produced sensors are often many times higher. Its utility will be therefore wide, seeing that apart from cars, hydrogen is also used in food, chemical, electronic and pharmaceutical industry, for wielding and cutting. The ability to detect other gases expands the scope of its use even more.
The uniqueness of the technical design and its industrial applicability is confirmed by granting protection in the form of a utility model by the Industrial Property Office of the Slovak Republic.
“The new technical design of the gas sensor with high potential for practical application in industry is another example of the Comenius University’s research linked to the practice. It is particularly valuable that it may contribute to the spread of environmentally friendly hydrogen technologies,” says about the benefits of the research prof. RNDr. Karol Mičieta, PhD., Rector of the Comenius University in Bratislava.
These results were together with physical model created in collaboration with theoretical physicists from the Slovak Academy of Sciences, published in reputable peer-reviewed journal Sensors and Actuators B: Chemical.
Source: PhDr. Andrea Földváryová
Head of the Department of Public Relations of the Comenius University in Bratislava
Photo 2: Faculty of Mathematics, Physics and Informatics of the Comenius University
Translated: Andrej Mišech
Published by: ZČ
Assigned to article:
22. Jul. 2015