A recently published article on the impact of hydrogen sensor miniaturisation shows that in some cases the performance of micro-machined sensors is better in comparison to conventional ones, while in others significant degradations may occur. The study was carried out by the JRC in collaboration with the US National Renewable Energy Laboratory and the University of Québec Trois-Rivières.
Hydrogen has been recognised as a viable energy carrier and its use is rapidly expanding. Sensors are needed for its detection as it is both odour- and colourless, and hence impossible to perceive for human beings. Miniaturised versions of conventional hydrogen gas sensors are being developed as they can offer many advantages including reduced costs, mass production capabilities and faster response times.
This paper assesses the promises and pitfalls of commercial micro-machined sensing elements in comparison to their conventional counterpart. Although some performance improvements were observed, such as faster response times, many micro-machined sensors were plagued with significant degradations including reduced dynamic measuring range, premature failure and poor repeatability. Furthermore, actual sensor performance did not always match with what the manufacturers claimed.
Although there are still shortcomings, there is potential in the approach of micro-machining hydrogen safety sensors. Economy-of-scale manufacturing techniques, made possible by micro-machining, will for example reduce the unit costs of sensing elements.
By highlighting the improvements and shortcomings, end-users will be able to better select the most suitable sensor. This research is a step towards emerging technology validation, supports the development of devices essential for safe hydrogen use in a hydrogen-inclusive economy and provides science-based advice on correct deployment of hydrogen safety sensors.